Verlängerung der QT-Zeit
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Eklärungen für Patienten zu den Wirkstoffen
Für die Kombination von Citalopram und Tramadol liegen uns keine zusätzlichen Warnhinweise vor. Bitte konsultieren Sie zusätzlich die jeweiligen Fachinformationen.
|Citalopram||1 [0.55,5.07] 1,2||1|
|Tramadol||1.23 [0.71,3.41] 2,3||1.23|
Die genannten Expositionsveränderungen beziehen sich jeweils auf Veränderungen der Plasmakonzentrations-Zeit-Kurve [ AUC ]. Die Exposition von Tramadol erhöht sich auf 123%, wenn eine Kombination mit Citalopram (123%) erfolgt. Die AUC liegt dabei je nach CYP2D6, CYP2B6
Für die Berechnung der individuellen Expositionsveränderungen durch die Wechselwirkungen werden als Ausgangsbasis die pharmakokinetischen Parameter der durchschnittlichen Population verwendet.
Citalopram hat eine mittlere orale Bioverfügbarkeit [ F ] von 80%, weshalb die maximalen Plasmaspiegel [ Cmax ] sich bei einer Interaktion tendentiell verändern. Die terminale Halbwertszeit [ t12 ] ist mit 35 Stunden eher lang und konstante Plasmaspiegel [ Css ] werden erst nach mehr als 140 Stunden erreicht. Die Proteinbindung [ Pb ] ist mit 80% mässig stark und das Verteilungsvolumen [ Vd ] ist mit 980 Liter sehr gross, da die Substanz eine tiefe hepatische Extraktionsrate von 0.19 besitzt, kann eine Verdrängung aus der Proteinbindung [Pb] im Rahmen einer Interaktion die Exposition erhöhen. Die Metabolisierung findet unter anderem über CYP2C19, CYP2D6 und CYP3A4 statt und der aktive Transport erfolgt insbesondere über PGP. Unter anderem ist Citalopram ein Hemmer von CYP2D6.
Tramadol hat eine mittlere orale Bioverfügbarkeit [ F ] von 66%, weshalb die maximalen Plasmaspiegel [ Cmax ] sich bei einer Interaktion tendentiell verändern. Die terminale Halbwertszeit [ t12 ] ist mit 4.5 Stunden eher kurz und konstante Plasmaspiegel [ Css ] werden schnell erreicht. Die Proteinbindung [ Pb ] ist mit 20% sehr schwach und das Verteilungsvolumen [ Vd ] ist mit 238 Liter sehr gross. da die Substanz eine tiefe hepatische Extraktionsrate von 0.24 besitzt, kann eine Verdrängung aus der Proteinbindung [Pb] im Rahmen einer Interaktion die Exposition erhöhen. Ungefähr 30.0% einer verabreichten Dosis werden unverändert über die Niere ausgeschieden und dieser Anteil wird selten durch Interaktionen verändert. Die Metabolisierung findet unter anderem über CYP2B6, CYP2D6 und CYP3A4 statt und der aktive Transport erfolgt insbesondere über UGT1A1.
|Serotonerge Effekte a||4||++||++|
Das Risiko für ein serotonerges Syndrom ist erhöht, aber ohne exakte
Bewertung: Citalopram und Tramadol modulieren das serotonerge System in moderatem Ausmass.
|Kiesel & Durán b||2||+||+|
Empfehlung: Insbesondere nach einer Dosiserhöhung und bei Dosierungen im oberen therapeutischen Bereich sollte vorsichtshalber auf anticholinerge Symptome geachtet werden.
Bewertung: Citalopram und Tramadol beeinflussen das anticholinerge System nur mild. Das Risiko für ein anticholinerge Syndrom ist bei dieser Medikation eher als gering einzustufen, wenn die Dosierung sich im üblichen Bereich befindet.
Verlängerung der QT-Zeit
Bewertung: In Kombination können Citalopram und Tramadol potentiell ventrikuläre Arrhythmien vom Typ Torsades de pointes auslösen.
Diaphorese (11.5%): Citalopram
Juckreiz (7.4%): Tramadol
Durchfall (8%): Citalopram
Verlust von Appetit: Citalopram
Agitation (6.5%): Citalopram
Abnorme Ejakulation (6.1%): Citalopram
Erektile Dysfunktion: Citalopram
Müdigkeit (5%): Citalopram
Atemnot (4.9%): Tramadol
Verlängerte Blutungszeit: Citalopram
Basierend auf Ihren
Abstract: This histological and immunohistochemical study of 6 food handlers affected by immediate contact dermatitis due to foods shows that apparently normal skin of patients with this condition presents several histological and immunohistochemical abnormalities. Skin biopsies of normal hand skin showed focal parakeratosis and moderately dense dermal infiltrates. Immunohistochemistry showed an increased number of Langerhans cells in the epidermis and in the superficial dermis and a mononuclear dermal infiltrate consisting of peripheral T lymphocytes with a CD4/CD8 ratio of 5-6/1. Biopsies of the immediate vesicular reactions induced by foods showed spongiotic vesicles within the epidermis and a moderate to dense mononuclear dermal perivascular infiltrate. The immunohistochemical features were similar to those described in apparently normal skin. The mechanism of this immediate vesicular reaction requires further research. The rapid appearance of the lesions (after 20-30 min) probably excludes an immunological cell-mediated pathogenesis. A non-immunological mechanism due to direct liberation of mediators by foods is more readily conceivable than an immediate immunological type of contact reaction.
Abstract: No Abstract available
Abstract: (+/-)-Tramadol is a synthetic 4-phenyl-piperidine analogue of codeine. It is a central analgesic with a low affinity for opioid receptors. Its selectivity for mu receptors has recently been demonstrated, and the M1 metabolite of tramadol, produced by liver O-demethylation, shows a higher affinity for opioid receptors than the parent drug. The rate of production of this M1 derivative (O-demethyl tramadol), is influenced by a polymorphic isoenzyme of the debrisoquine-type, cytochrome P450 2D6 (CYP2D6). Nevertheless, this affinity for mu receptors of the CNS remains low, being 6000 times lower than that of morphine. Moreover, and in contrast to other opioids, the analgesic action of tramadol is only partially inhibited by the opioid antagonist naloxone, which suggests the existence of another mechanism of action. This was demonstrated by the discovery of a monoaminergic activity that inhibits noradrenaline (norepinephrine) and serotonin (5-hydroxytryptamine; 5-HT) reuptake, making a significant contribution to the analgesic action by blocking nociceptive impulses at the spinal level. (+/-)-Tramadol is a racemic mixture of 2 enantiomers, each one displaying differing affinities for various receptors. (+/-)-Tramadol is a selective agonist of mu receptors and preferentially inhibits serotonin reuptake, whereas (-)-tramadol mainly inhibits noradrenaline reuptake. The action of these 2 enantiomers is both complementary and synergistic and results in the analgesic effect of (+/-)-tramadol. After oral administration, tramadol demonstrates 68% bioavailability, with peak serum concentrations reached within 2 hours. The elimination kinetics can be described as 2-compartmental, with a half-life of 5.1 hours for tramadol and 9 hours for the M1 derivative after a single oral dose of 100mg. This explains the approximately 2-fold accumulation of the parent drug and its M1 derivative that is observed during multiple dose treatment with tramadol. The recommended daily dose of tramadol is between 50 and 100mg every 4 to 6 hours, with a maximum dose of 400 mg/day; the duration of the analgesic effect after a single oral dose of tramadol 100mg is about 6 hours. Adverse effects, and nausea in particular, are dose-dependent and therefore considerably more likely to appear if the loading dose is high. The reduction of this dose during the first days of treatment is an important factor in improving tolerability. Other adverse effects are generally similar to those of opioids, although they are usually less severe, and can include respiratory depression, dysphoria and constipation. Tramadol can be administered concomitantly with other analgesics, particularly those with peripheral action, while drugs that depress CNS function may enhance the sedative effect of tramadol. Tramadol should not be administered to patients receiving monoamine oxidase inhibitors, and administration with tricyclic antidepressant drugs should also be avoided. Tramadol has pharmacodynamic and pharmacokinetic properties that are highly unlikely to lead to dependence. This was confirmed by various controlled studies and postmarketing surveillance studies, which reported an extremely small number of patients developing tolerance or instances of tramadol abuse. Tramadol is a central acting analgesic which has been shown to be effective and well tolerated, and likely to be of value for treating several pain conditions (step II of the World Health Organization ladder) where treatment with strong opioids is not required.
Abstract: OBJECTIVE: To compare the pharmacokinetics of the antidepressant citalopram and its metabolites demethylcitalopram and didemethylcitalopram in subjects with moderate renal insufficiency and subjects with hepatic cirrhosis with that in healthy subjects. METHODS: Pharmacokinetic parameters from three individual, open-label, phase I trials were derived following single oral or intravenous citalopram dose (40 mg) to healthy subjects and a single oral dose (20 mg) to patients. Serum and urine concentrations of citalopram and metabolites were determined using a validated HPLC method. RESULTS: The absolute bioavailability of citalopram tablets in healthy subjects was 80%. The renal clearance was a minor component (<20%) of the total elimination of citalopram. Serum Cmax and t(max) for citalopram were essentially unaffected by the occurrence of renal or hepatic disease. In comparison with healthy subjects, renal impairment was associated with a significant reduction in the renal elimination of citalopram and its two metabolites and a slight prolongation of serum citalopram t1/2 (49.5 h vs 36.8 h in healthy subjects). Cirrhosis resulted in significant decrease in citalopram CLoral (0.21 vs 0.331 x h(-1) x kg(-1) in healthy subjects) and increase in Vz x f(-1) with an approximately twofold increase in t1/2 (83.4 h vs 36.8 h in healthy subjects). Indices of renal (creatinine or 51Cr-EDTA clearances) and hepatic (galactose elimination capacity or Child-Pugh score) function were poor predictors of the changes in the pharmacokinetics of citalopram and its metabolites in these populations. CONCLUSION: No reduction of citalopram dosage is warranted in patients with moderately impaired renal function. However, that may not apply for patients with severe renal failure. In patients with impaired hepatic function, prescription of a lower dosage of citalopram may be appropriate.
Abstract: OBJECTIVE: To study the effects of severe renal failure and haemodialysis on the pharmacokinetics of citalopram. METHODS: Four patients with renal failure undergoing haemodialysis and eight healthy controls were given a single dose of citalopram. The concentrations of citalopram and its metabolites desmethylcitalopram and didesmethylcitalopram were measured in serum and urine. On a different day, the four patients undergoing haemodialysis were given another single dose of citalopram, and the drug concentrations were measured in serum from the artery leading to the dialyser and in the dialysate. In addition, one anuric patient treated with citalopram on a regular basis was included in the study. RESULTS: There were no significant differences between the two groups in any of the pharmacokinetic parameters with the exception of the renal clearance of citalopram, which was significantly lower in the renal failure group than in the control group (1.70 ml/min versus 66.2 ml/min, P<0.001). Oral clearance of citalopram was almost identical in the two groups (452 ml/min versus 456 ml/min). The process of haemodialysis cleared about 1% of the dose as citalopram and 1% as desmethylcitalopram only. CONCLUSION: Severe renal failure does not affect the pharmacokinetics of citalopram and modification of the usual citalopram dose does thus not seem to be necessary. The contribution of haemodialysis to the total elimination of citalopram is negligible.
Abstract: No Abstract available
Abstract: Tramadol, a centrally acting analgesic structurally related to codeine and morphine, consists of two enantiomers, both of which contribute to analgesic activity via different mechanisms. (+)-Tramadol and the metabolite (+)-O-desmethyl-tramadol (M1) are agonists of the mu opioid receptor. (+)-Tramadol inhibits serotonin reuptake and (-)-tramadol inhibits norepinephrine reuptake, enhancing inhibitory effects on pain transmission in the spinal cord. The complementary and synergistic actions of the two enantiomers improve the analgesic efficacy and tolerability profile of the racemate. Tramadol is available as drops, capsules and sustained-release formulations for oral use, suppositories for rectal use and solution for intramuscular, intravenous and subcutaneous injection. After oral administration, tramadol is rapidly and almost completely absorbed. Sustained-release tablets release the active ingredient over a period of 12 hours, reach peak concentrations after 4.9 hours and have a bioavailability of 87-95% compared with capsules. Tramadol is rapidly distributed in the body; plasma protein binding is about 20%. Tramadol is mainly metabolised by O- and N-demethylation and by conjugation reactions forming glucuronides and sulfates. Tramadol and its metabolites are mainly excreted via the kidneys. The mean elimination half-life is about 6 hours. The O-demethylation of tramadol to M1, the main analgesic effective metabolite, is catalysed by cytochrome P450 (CYP) 2D6, whereas N-demethylation to M2 is catalysed by CYP2B6 and CYP3A4. The wide variability in the pharmacokinetic properties of tramadol can partly be ascribed to CYP polymorphism. O- and N-demethylation of tramadol as well as renal elimination are stereoselective. Pharmacokinetic-pharmacodynamic characterisation of tramadol is difficult because of differences between tramadol concentrations in plasma and at the site of action, and because of pharmacodynamic interactions between the two enantiomers of tramadol and its active metabolites. The analgesic potency of tramadol is about 10% of that of morphine following parenteral administration. Tramadol provides postoperative pain relief comparable with that of pethidine, and the analgesic efficacy of tramadol can further be improved by combination with a non-opioid analgesic. Tramadol may prove particularly useful in patients with a risk of poor cardiopulmonary function, after surgery of the thorax or upper abdomen and when non-opioid analgesics are contraindicated. Tramadol is an effective and well tolerated agent to reduce pain resulting from trauma, renal or biliary colic and labour, and also for the management of chronic pain of malignant or nonmalignant origin, particularly neuropathic pain. Tramadol appears to produce less constipation and dependence than equianalgesic doses of strong opioids.
Abstract: No Abstract available
Abstract: Anticholinergic Drug Scale (ADS) scores were previously associated with serum anticholinergic activity (SAA) in a pilot study. To replicate these results, the association between ADS scores and SAA was determined using simple linear regression in subjects from a study of delirium in 201 long-term care facility residents who were not included in the pilot study. Simple and multiple linear regression models were then used to determine whether the ADS could be modified to more effectively predict SAA in all 297 subjects. In the replication analysis, ADS scores were significantly associated with SAA (R2 = .0947, P < .0001). In the modification analysis, each model significantly predicted SAA, including ADS scores (R2 = .0741, P < .0001). The modifications examined did not appear useful in optimizing the ADS. This study replicated findings on the association of the ADS with SAA. Future work will determine whether the ADS is clinically useful for preventing anticholinergic adverse effects.
Abstract: The objective of this study was to measure the anticholinergic activity (AA) of medications commonly used by older adults. A radioreceptor assay was used to investigate the AA of 107 medications. Six clinically relevant concentrations were assessed for each medication. Rodent forebrain and striatum homogenate was used with tritiated quinuclidinyl benzilate. Drug-free serum was added to medication and atropine standard-curve samples. For medications that showed detectable AA, average steady-state peak plasma and serum concentrations (C(max)) in older adults were used to estimate relationships between in vitro dose and AA. All results are reported in pmol/mL of atropine equivalents. At typical doses administered to older adults, amitriptyline, atropine, clozapine, dicyclomine, doxepin, L-hyoscyamine, thioridazine, and tolterodine demonstrated AA exceeding 15 pmol/mL. Chlorpromazine, diphenhydramine, nortriptyline, olanzapine, oxybutynin, and paroxetine had AA values of 5 to 15 pmol/mL. Citalopram, escitalopram, fluoxetine, lithium, mirtazapine, quetiapine, ranitidine, and temazepam had values less than 5 pmol/mL. Amoxicillin, celecoxib, cephalexin, diazepam, digoxin, diphenoxylate, donepezil, duloxetine, fentanyl, furosemide, hydrocodone, lansoprazole, levofloxacin, metformin, phenytoin, propoxyphene, and topiramate demonstrated AA only at the highest concentrations tested (patients with above-average C(max) values, who receive higher doses, or are frail may show AA). The remainder of the medications investigated did not demonstrate any AA at the concentrations examined. Psychotropic medications were particularly likely to demonstrate AA. Each of the drug classifications investigated (e.g., antipsychotic, cardiovascular) had at least one medication that demonstrated AA at therapeutic doses. Clinicians can use this information when choosing between equally efficacious medications, as well as in assessing overall anticholinergic burden.
Abstract: OBJECTIVES: To examine the longitudinal relationship between cumulative exposure to anticholinergic medications and memory and executive function in older men. DESIGN: Prospective cohort study. SETTING: A Department of Veterans Affairs primary care clinic. PARTICIPANTS: Five hundred forty-four community-dwelling men aged 65 and older with diagnosed hypertension. MEASUREMENTS: The outcomes were measured using the Hopkins Verbal Recall Test (HVRT) for short-term memory and the instrumental activity of daily living (IADL) scale for executive function at baseline and during follow-up. Anticholinergic medication use was ascertained using participants' primary care visit records and quantified as total anticholinergic burden using a clinician-rated anticholinergic score. RESULTS: Cumulative exposure to anticholinergic medications over the preceding 12 months was associated with poorer performance on the HVRT and IADLs. On average, a 1-unit increase in the total anticholinergic burden per 3 months was associated with a 0.32-point (95% confidence interval (CI)= 0.05-0.58) and 0.10-point (95% CI=0.04-0.17) decrease in the HVRT and IADLs, respectively, independent of other potential risk factors for cognitive impairment, including age, education, cognitive and physical function, comorbidities, and severity of hypertension. The association was attenuated but remained statistically significant with memory (0.29, 95% CI=0.01-0.56) and executive function (0.08, 95% CI=0.02-0.15) after further adjustment for concomitant non-anticholinergic medications. CONCLUSION: Cumulative anticholinergic exposure across multiple medications over 1 year may negatively affect verbal memory and executive function in older men. Prescription of drugs with anticholinergic effects in older persons deserves continued attention to avoid deleterious adverse effects.
Abstract: WHAT IS ALREADY KNOWN: During recent years some opioids have been associated with prolonged QT and torsade de pointes (TdP). In vitro testing has shown that most opioids can block the cardiac potassium channels. This indicates that QT prolongation and TdP could be a more general problem associated with the use of these drugs. WHAT THIS PAPER ADDS: This study is the first to show that oxycodone dose is associated with QT prolongation and in vitro blockade of hERG channels expressed in HEK293. Neither morphine nor tramadol doses are associated with the QT interval length. AIMS: During recent years some opioids have been associated with prolonged QT interval and torsade de pointes (TdP). In vitro patch clamp testing has shown that most opioids can block human ether-a-go-go related gene (hERG) channels that are known to underlie cardiac repolarizing I(Kr) current. This indicates that QT prolongation and TdP could be a more general problem associated with the use of these drugs. The aims of this study were to evaluate the association between different opioids and the QTc among patients and measure hERG activity under influence by opioids in vitro. METHODS: One hundred chronic nonmalignant pain patients treated with methadone, oxycodone, morphine or tramadol were recruited in a cross-sectional study. The QTc was estimated from a 12-lead ECG. To examine hERG activity in the presence of oxycodone, electrophysiological testing was conducted using Xenopus laevis oocytes and HEK293 cells expressing hERG channels. RESULTS: There were no differences in gender distribution or age between the treatment groups. The known association between methadone dose and QTc was confirmed (R(2) = 0.09; P = 0.02). Higher oxycodone dose was also associated with longer QTc (R(2) = 0.21; P = 0.02). A 100 mg higher oxycodone dose was associated with a 10 ms(1/2) (95% CI 2-19) longer QTc. Neither morphine nor tramadol dose was associated with the QTc. Electrophysiological testing revealed low-affinity inhibition of the potassium current through hERG channels expressed in HEK293 cells (IC(50) = 171 microM oxycodone). CONCLUSIONS: Among patients treated with methadone or oxycodone, higher doses were associated with longer QTc. Oxycodone is capable of inhibiting hERG channels in vitro.
Abstract: BACKGROUND: Cognitive decline is common in Parkinson's disease (PD). Although some of the aetiological factors are known, it is not yet known whether drugs with anticholinergic activity (AA) contribute to this cognitive decline. Such knowledge would provide opportunities to prevent acceleration of cognitive decline in PD. OBJECTIVE: To study whether the use of agents with anticholinergic properties is an independent risk factor for cognitive decline in patients with PD. METHODS: A community-based cohort of patients with PD (n=235) were included and assessed at baseline. They were reassessed 4 and 8 years later. Cognition was assessed using the Mini-Mental State Examination (MMSE). A detailed assessment of the AA of all drugs prescribed was made, and AA was classified according to a standardised scale. Relationships between cognitive decline and AA load and duration of treatment were assessed using bivariate and multivariate statistical analyses. RESULTS: More than 40% used drugs with AA at baseline. During the 8-year follow-up, the cognitive decline was higher in those who had been taking AA drugs (median decline on MMSE 6.5 points) compared with those who had not taken such drugs (median decline 1 point; p=0.025). In linear regression analyses adjusting for age, baseline cognition and depression, significant associations with decline on MMSE were found for total AA load (standardised beta=0.229, p=0.04) as well as the duration of using AA drugs (standardised beta 0.231, p=0.032). CONCLUSION: Our findings suggest that there is an association between anticholinergic drug use and cognitive decline in PD. This may provide an important opportunity for clinicians to avoid increasing progression of cognitive decline by avoiding drugs with AA. Increased awareness by clinicians is required about the classes of drugs that have anticholinergic properties.
Abstract: No Abstract available
Abstract: PURPOSE: We assessed possible drug interactions of tramadol given concomitantly with the potent CYP2B6 inhibitor ticlopidine, alone or together with the potent CYP3A4 and P-glycoprotein inhibitor itraconazole. METHODS: In a randomized, placebo-controlled cross-over study, 12 healthy subjects ingested 50 mg of tramadol after 4 days of pretreatment with either placebo, ticlopidine (250 mg twice daily) or ticlopidine plus itraconazole (200 mg once daily). Plasma and urine concentrations of tramadol and its active metabolite O-desmethyltramadol (M1) were monitored over 48 h and 24 h, respectively. RESULTS: Ticlopidine increased the mean area under the plasma concentration-time curve (AUC0-∞) of tramadol by 2.0-fold (90 % confidence interval (CI) 1.6-2.4; p < 0.001) and Cmax by 1.4-fold (p < 0.001), and reduced its oral and renal clearance (p < 0.01). Ticlopidine reduced the AUC0-3 of M1 (p < 0.001) and the ratio of the AUC0-∞ of M1 to that of tramadol, but did not influence the AUC0-∞ of M1. Tramadol or M1 pharmacokinetics did not differ between the ticlopidine alone and ticlopidine plus itraconazole phases. CONCLUSIONS: Ticlopidine increased exposure to tramadol, reduced its renal clearance and inhibited the formation of M1, most likely via inhibition of CYP2B6 and/or CYP2D6. The addition of itraconazole to ticlopidine did not modify the outcome of the drug interaction. Concomitant clinical use of ticlopidine and tramadol may enhance the risk of serotonergic effects, especially when higher doses of tramadol are used.
Abstract: PURPOSE: Tramadol is mainly metabolized by the cytochrome P450 (CYP) 2D6, CYP2B6 and CYP3A4 enzymes. The aim of this study was to evaluate the effect of enzyme induction with rifampicin on the pharmacokinetics and pharmacodynamics of oral and intravenous tramadol. METHODS: This was a randomized placebo-controlled crossover study design with 12 healthy subjects. After pretreatment for 5 days with rifampicin (600 mg once daily) or placebo, subjects were given tramadol either 50 mg intravenously or 100 mg orally. Plasma concentrations of tramadol and its active main metabolite O-desmethyltramadol (M1) were determined over 48 h. Analgesic and behavioral effects and whole blood 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) concentrations were measured. RESULTS: Rifampicin reduced the mean area under the time-concentration curve (AUC0-∞) of intravenously administered tramadol by 43 % and that of M1 by 58 % (P < 0.001); it reduced the AUC0-∞ of oral tramadol by 59 % and that of M1 by 54 % (P < 0.001). Rifampicin increased the clearance of intravenous tramadol by 67 % (P < 0.001). Bioavailability of oral tramadol was reduced by rifampicin from 66 to 49 % (P = 0.002). The pharmacological effects of tramadol or whole blood serotonin concentrations were not influenced by pretreatment with rifampicin. CONCLUSIONS: Rifampicin markedly decreased the exposure to tramadol and M1 after both oral and intravenous administration. Therefore, rifampicin and other potent enzyme inducers may have a clinically important interaction with tramadol regardless of the route of its administration.
Abstract: No Abstract available
Abstract: We comprehensively reviewed published literature to determine whether it supported the link between corrected QT (QTc) interval prolongation and torsade de pointes (TdP) for the 11 second-generation antipsychotics and seven second-generation antidepressants commonly implicated in these complications. Using PubMed and EMBASE, we identified four thorough QT studies (one each for iloperidone, ziprasidone, citalopram, and escitalopram), 40 studies specifically designed to assess QTc interval prolongation or TdP, 58 publications based on data from efficacy and safety trials, 18 toxicology studies, and 102 case reports. Thorough QT studies, QTc prolongation-specific studies, and studies based on efficacy and safety trials did not link drug-associated QTc interval prolongation with TdP. They only showed that the drugs reviewed caused varying degrees of QTc interval prolongation, and even that information was not clear and consistent enough to stratify individual drugs for this risk. The few toxicology studies provided valuable information but their findings are pertinent only to situations of drug overdose. Case reports were most informative about the drug-QTc interval prolongation-TdP link. At least one additional well established risk factor for QTc prolongation was present in 92.2 % of case reports. Of the 28 cases of TdP, six (21.4 %) experienced it with QTc interval <500 ms; 75 % of TdP cases occurred at therapeutic doses. There is little evidence that drug-associated QTc interval prolongation by itself is sufficient to predict TdP. Future research needs to improve its precision and broaden its scope to better understand the factors that facilitate or attenuate progression of drug-associated QTc interval prolongation to TdP.
Abstract: OBJECTIVES: The aim of this systematic review is to identify case reports of citalopram use resulting in QTc prolongation, torsades de pointes, or both, in the medical literature. METHODS: A literature search was conducted of PubMed, MEDLINE, EMBASE, Scopus, and PsycINFO databases for case reports published in any language that reported the relationship between citalopram use and the development of QTc prolongation or torsades de pointes or both. In addition, bibliographic databases of published articles were searched for additional cases. RESULTS: A total of 18 case reports of citalopram use resulting in QTc prolongation were identified. Of these, 10 cases were also associated with the development of torsades de pointes. A total of 14 cases occurred in women and 4 in men. There were 7 cases involving an overdose with citalopram. Of the 18 cases, 12 occurred in individuals who were aged <60 years and 6 were in individuals aged >60 years. In 8 of the 18 cases, the individuals were taking a dose between 20 and 60mg of citalopram in a day. Hypertension was the most common comorbid medical condition, as seen in 5 of the cases. CONCLUSIONS: QTc prolongation or torsades de pointes are infrequently reported adverse effects associated with citalopram use.
Abstract: BACKGROUND AND OBJECTIVE: Tramadol hydrochloride is used worldwide as an analgesic drug with a unique dual function. The metabolic enzymes cytochrome P450 (CYP) 3A4, CYP2B6, and CYP2D6 and the various transporters [adenosine triphosphate-binding cassette B1/multidrug resistance 1/P-glycoprotein, organic cation transporter 1, serotonin transporter (SERT), norepinephrine transporter (NET)] and receptor genes (opioid receptor μ 1 gene) give possible genetic differences that might affect the pharmacokinetics and/or pharmacodynamics of tramadol. Therefore, the aim of this review is to present a systematic walkthrough of all possible genetic factors involved in the pharmacology of tramadol. METHOD: A systematic literature search was conducted in PubMed and EMBASE involving all metabolic enzymes, drug transporters and receptors, as well as SERT and NET that are involved in the pharmacokinetics and pharmacodynamics of tramadol. An additional search on population pharmacokinetics with genetic factors as covariates was performed separately. RESULTS: A total of 56 studies (45 cohort and case-control studies, three case reports, six in vitro studies, and two animal studies) were included. CONCLUSION: In this systematic review, the current knowledge on all possible genetic factors that might influence the metabolism or clinical efficacy of tramadol has been collected and summarized. Only the effect of CYP2D6 polymorphisms on the metabolism of tramadol and the consequent effect on pain relief has been thoroughly studied and sufficiently established as clinically relevant.
Abstract: UNLABELLED: In recent years, several cases of torsade de pointes have been associated with many opioids. However, to present no cases have been reported with tramadol. OBJECTIVE: To evaluate the effect of tramadol on QT-interval in the clinical setting. RESEARCH DESIGN AND METHODS: Medical history and comorbidities predisposing to QT interval prolongation were registered for patients requiring medical assistance that involved tramadol administration. Ionograms and ECGs were performed at baseline and intratreatment; QT interval was analyzed after correction with Bazzet, Fridericia, Framinghan and Hogdes formula. RESULTS: 115 patients were studied (50.4% males) All patients had received tramadol 150-400 mg/day during 3.0-5.0 days at the moment of intratreatment control. Plasma concentrations of tramadol were 201-1613 ng/mL. Intratreatment electrocardiographic control, as mean ± SD (range), showed QTcB 372±32 (305 to 433), QTcFri 356±37 (281 to 429), QTcFra 363±33 (299 to 429), QTcH 362±30 (304 to 427), ΔQTcB 26±40 (-73 to 110), ΔQTcFri 24±48 (-97 to 121), ΔQTcFra 22±42 (-81 to 109) and .QTcH 22±38 (-68 to 110) ms. QTc interval presents high correlation with plasma tramadol concentrations (for .QTc, R>0.77). Renal failure was associated with a relative risk for ΔQTc > 30 ms of 1.90 (IC95% 1.31-2.74) and for ΔQTc > 60 ms of 4.74 (IC95% 2.57-8.74). No patient had evidence of arrhythmia during the present study. CONCLUSION: Tramadol produces QTc interval prolongation in good correlation with plasma drug concentrations; renal failure is a risk factor for higher concentration and QT prolongation by tramadol.
Abstract: We evaluated the effects of therapeutic and supratherapeutic doses of tramadol hydrochloride on the corrected QT (QTc) interval in healthy adults (aged 18-55 years) in a randomized, phase I, double-blind, placebo- and positive-controlled, multiple-dose, 4-way crossover study. Participants were randomized to receive 1 of 4 treatments (A-D), 1 each in 4 treatment periods (1-4), separated by a washout period (7-15 days). Treatment A comprised tramadol 400 mg (therapeutic dose) on days 1 through 3, tramadol 100 mg and moxifloxacin-matched placebo on day 4, and placebo on all 4 days. Treatment B comprised tramadol 600 mg (supratherapeutic dose) on days 1 through 3, and tramadol 150 mg and moxifloxacin-matched placebo on day 4. Treatment C comprised placebo on days 1 through 4 and moxifloxacin-matched placebo on day 4. Treatment D comprised placebo on days 1 through 4 and moxifloxacin 400 mg on day 4. Of 68 participants enrolled, 57 (83.8%) completed the study. Both therapeutic and supratherapeutic doses of tramadol were shown to be noninferior to placebo regarding their effect on QTc prolongation. Sixty-one of 68 (89.7%) participants reported at least 1 treatment-emergent adverse event (mild); nausea was the most frequently reported treatment-emergent adverse event. Summarizing, tramadol at doses up to 600 mg/day did not cause clinically relevant QTc interval prolongation in healthy adults.
Abstract: BACKGROUND: Anticholinergic drugs put elderly patients at a higher risk for falls, cognitive decline, and delirium as well as peripheral adverse reactions like dry mouth or constipation. Prescribers are often unaware of the drug-based anticholinergic burden (ACB) of their patients. This study aimed to develop an anticholinergic burden score for drugs licensed in Germany to be used by clinicians at prescribing level. METHODS: A systematic literature search in pubmed assessed previously published ACB tools. Quantitative grading scores were extracted, reduced to drugs available in Germany, and reevaluated by expert discussion. Drugs were scored as having no, weak, moderate, or strong anticholinergic effects. Further drugs were identified in clinical routine and included as well. RESULTS: The literature search identified 692 different drugs, with 548 drugs available in Germany. After exclusion of drugs due to no systemic effect or scoring of drug combinations (n = 67) and evaluation of 26 additional identified drugs in clinical routine, 504 drugs were scored. Of those, 356 drugs were categorised as having no, 104 drugs were scored as weak, 18 as moderate and 29 as having strong anticholinergic effects. CONCLUSIONS: The newly created ACB score for drugs authorized in Germany can be used in daily clinical practice to reduce potentially inappropriate medications for elderly patients. Further clinical studies investigating its effect on reducing anticholinergic side effects are necessary for validation.
Abstract: In pediatric PBPK models, age-related changes in the body are known to occur. Given the sparsity of and the variability associated with relevant physiological parameters, different PBPK software providers may vary in their system's data. In this work, three commercially available PBPK software packages (PK-Sim®, Simcyp®, and Gastroplus®) were investigated regarding their differences in system-related information, possibly affecting clearance prediction. Three retrograde PBPK clearance models were set up to enable prediction of pediatric tramadol clearance. These models were qualified in terms of total, CYP2D6, and renal clearance in adults. Tramadol pediatric clearance predictions from PBPK were compared with a pooled popPK model covering clearance ranging from neonates to adults. Fold prediction errors were used to evaluate the results. Marked differences in liver clearance prediction between PBPK models were observed. In general, the prediction bias of total clearance was greatest at the youngest population and decreased with age. Regarding CYP2D6 and renal clearance, important differences exist between PBPK software tools. Interestingly, the PBPK model with the shortest CYP2D6 maturation half-life (PK-Sim) agreed best with the in vivo CYP2D6 maturation model. Marked differences in physiological data explain the observed differences in hepatic clearance prediction in early life between the various PBPK software providers tested. Consensus on the most suited pediatric data to use should harmonize and optimize pediatric clearance predictions. Moreover, the combination of bottom-up and top-down approaches, using a convenient probe substrate, has the potential to update system-related parameters in order to better represent pediatric physiology.
Abstract: OBJECTIVE: To determine the risk of prolonged opioid use in patients receiving tramadol compared with other short acting opioids. DESIGN: Observational study of administrative claims data. SETTING: United States commercial and Medicare Advantage insurance claims (OptumLabs Data Warehouse) January 1, 2009 through June 30, 2018. PARTICIPANTS: Opioid-naive patients undergoing elective surgery. MAIN OUTCOME MEASURE: Risk of persistent opioid use after discharge for patients treated with tramadol alone compared with other short acting opioids, using three commonly used definitions of prolonged opioid use from the literature: additional opioid use (defined as at least one opioid fill 90-180 days after surgery); persistent opioid use (any span of opioid use starting in the 180 days after surgery and lasting ≥90 days); and CONSORT definition (an opioid use episode starting in the 180 days after surgery that spans ≥90 days and includes either ≥10 opioid fills or ≥120 days' supply of opioids). RESULTS: Of 444 764 patients who met the inclusion criteria, 357 884 filled a discharge prescription for one or more opioids associated with one of 20 included operations. The most commonly prescribed post-surgery opioid was hydrocodone (53.0% of those filling a single opioid), followed by short acting oxycodone (37.5%) and tramadol (4.0%). The unadjusted risk of prolonged opioid use after surgery was 7.1% (n=31 431) with additional opioid use, 1.0% (n=4457) with persistent opioid use, and 0.5% (n=2027) meeting the CONSORT definition. Receipt of tramadol alone was associated with a 6% increase in the risk of additional opioid use relative to people receiving other short acting opioids (incidence rate ratio 95% confidence interval 1.00 to 1.13; risk difference 0.5 percentage points; P=0.049), 47% increase in the adjusted risk of persistent opioid use (1.25 to 1.69; 0.5 percentage points; P<0.001), and 41% increase in the adjusted risk of a CONSORT chronic opioid use episode (1.08 to 1.75; 0.2 percentage points; P=0.013). CONCLUSIONS: People receiving tramadol alone after surgery had similar to somewhat higher risks of prolonged opioid use compared with those receiving other short acting opioids. Federal governing bodies should consider reclassifying tramadol, and providers should use as much caution when prescribing tramadol in the setting of acute pain as for other short acting opioids.
Abstract: INTRODUCTION: Citalopram is a selective serotonin reuptake inhibitor used for treatment of depression. Metabolism is primarily through CYP3A4 and CYP2C19; activity of the latter can vary depending on genetics. Although rare after single agent exposure, large citalopram ingestions can lead to serotonin syndrome. We report a case of citalopram overdose in an intermediate CYP2C19 metabolizer complicated by severe serotonin syndrome. CASE DETAILS: A 25-year-old female presented after intentional citalopram overdose with seizures, tachycardia, persistent neuromuscular findings, and severe hyperthermia requiring aggressive sedation and cooling. Protracted symptoms required critical care services throughout a 14 day hospital stay despite traditional treatment of serotonin syndrome. Pharmacogenomic studies revealed intermediate CYP2C19 metabolism which reduces citalopram inactivation and may cause increased levels and toxicity. DISCUSSION: In the majority of serotonin syndrome cases, symptoms resolve rapidly after treatment initiation and discontinuation of the offending agents. Severe cases are typically associated with ingestion of multiple serotonergic agents. Our patient had severe toxicity after single agent ingestion. Pharmacogenetic testing identified abnormal CYP2C19 activity and previous cases have associated enzyme dysfunction and citalopram toxicity. CONCLUSION: Citalopram overdose may be associated with severe serotonin syndrome and further investigation is warranted to understand the impact of enzyme genotype on toxicity.
Abstract: Genetic variants in the hepatic uptake transporter OCT1, observed in 9% of Europeans and white Americans, are known to affect pharmacokinetics and efficacy of tramadol, morphine, and codeine. Here, we report further opioids to be substrates and inhibitors of OCT1. Methylnaltrexone, hydromorphone, oxymorphone, and meptazinol were identified as OCT1 substrates. Methylnaltrexone is the strongest OCT1 substrate currently reported. It showed 86-fold higher accumulation in OCT1-overexpressing cells compared to control cells. We observed substantial differences in the inhibitory potency among structurally highly similar morphinan opioids (ICranged from 6.4 μM for dextrorphan to 2 mM for oxycodone). The ether linkage of C4-C5 in the morphinan ring leads to a strong reduction of inhibitory potency. In conclusion, although polyspecific, OCT1 possesses a strong selectivity for its ligands. In contrast to methylnaltrexone and hydromorphone, oxycodone and hydrocodone do not interact with OCT1 and may be safer for use in individuals with genetic OCT1 deficiency.