QT time prolongation
Adverse drug events
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Explanations of the substances for patients
We have no additional warnings for the combination of abiraterone and citalopram. Please also consult the relevant specialist information.
|Citalopram||1.96 [0.75,5.26] 1,2||1.96|
The changes in exposure mentioned relate to changes in the plasma concentration-time curve [AUC]. Citalopram exposure increases to 196%, when combined with abiraterone (196%). The AUC is between 75% and 526% depending on the CYP2C19, CYP2D6
The pharmacokinetic parameters of the average population are used as the starting point for calculating the individual changes in exposure due to the interactions.
Abiraterone has a mean oral bioavailability [ F ] of 50%, which is why the maximum plasma levels [Cmax] tend to change with an interaction. The terminal half-life [ t12 ] is 18 hours and constant plasma levels [ Css ] are reached after approximately 72 hours. The protein binding [ Pb ] is very strong at 99.8% and the volume of distribution [ Vd ] is very large at 2815 liters, The metabolism mainly takes place via CYP3A4.
Citalopram has a mean oral bioavailability [ F ] of 80%, which is why the maximum plasma levels [Cmax] tend to change with an interaction. The terminal half-life [ t12 ] is rather long at 35 hours and constant plasma levels [ Css ] are only reached after more than 140 hours. The protein binding [ Pb ] is moderately strong at 80% and the volume of distribution [ Vd ] is very large at 980 liters, Since the substance has a low hepatic extraction rate of 0.19, displacement from protein binding [Pb] in the context of an interaction can increase exposure. The metabolism takes place via CYP2C19, CYP2D6 and CYP3A4, among others and the active transport takes place in particular via PGP.
|Serotonergic Effects a||2||Ø||++|
Recommendation: As a precautionary measure, symptoms of serotonergic overstimulation should be taken into account, especially after increasing the dose and at doses in the upper therapeutic range.
Rating: Citalopram modulates the serotonergic system to a moderate extent. The risk of a serotonergic syndrome can be classified as low with this medication if the dosage is in the usual range. According to our knowledge, abiraterone does not increase serotonergic activity.
|Kiesel & Durán b||1||Ø||+|
Recommendation: As a precaution, attention should be paid to anticholinergic symptoms, especially after increasing the dose and at doses in the upper therapeutic range.
Rating: Citalopram only has a mild effect on the anticholinergic system. The risk of anticholinergic syndrome with this medication is rather low if the dosage is in the usual range. According to our findings, abiraterone does not increase anticholinergic activity.
QT time prolongation
Rating: In combination, abiraterone and citalopram can potentially trigger ventricular arrhythmias of the torsades de pointes type.
General adverse effects
|Side effects||∑ frequency||abi||cit|
|Peripheral edema||20.0 %||20.0||n.a.|
Elevated ALT (13%): abiraterone
Elevated AST (13%): abiraterone
Constipation (13%): citalopram
Vomiting (12%): citalopram
Loss of appetite: citalopram
Tremor (12%): citalopram
Cerebrovascular accident: citalopram
Diaphoresis (11.5%): citalopram
Urinary tract infection (10%): abiraterone
Agitation (6.5%): citalopram
Abnormal ejaculation (6.1%): citalopram
Erectile dysfunction: citalopram
Orgasm disorder: citalopram
Sepsis (5.5%): abiraterone
Fatigue (5%): citalopram
Atrial fibrillation (2.6%): abiraterone
Angina pectoris (1.6%): abiraterone
Weight loss: citalopram
Prolonged bleeding time: citalopram
Based on your
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: 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: 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: 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: Three open-label, single-dose studies investigated the impact of hepatic or renal impairment on abiraterone acetate pharmacokinetics and safety/tolerability in non-cancer patients. Patients (n = 8 each group) with mild/moderate hepatic impairment or end-stage renal disease (ESRD), and age-, BMI-matched healthy controls received a single oral 1,000 mg abiraterone acetate (tablet dose); while patients (n = 8 each) with severe hepatic impairment and matched healthy controls received 125- and 2,000-mg abiraterone acetate (suspension doses), respectively (systemic exposure of abiraterone acetate suspension is approximately half to that of tablet formulation). Blood was sampled at specified timepoints up to 72 or 96 hours postdose to measure plasma abiraterone concentrations. Abiraterone exposure was comparable between healthy controls and patients with mild hepatic impairment or ESRD, but increased by 4-fold in patients with moderate hepatic impairment. Despite a 16-fold reduction in dose, abiraterone exposure in patients with severe hepatic impairment was about 22% and 44% of the Cmax and AUC∞ of healthy controls, respectively. These results suggest that abiraterone pharmacokinetics were not changed markedly in patients with ESRD or mild hepatic impairment. However, the capacity to eliminate abiraterone was substantially compromised in patients with moderate or severe hepatic impairment. A single-dose administration of abiraterone acetate was well-tolerated.
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: Two novel oral drugs that target androgen signaling have recently become available for the treatment of metastatic castration-resistant prostate cancer (mCRPC). Abiraterone acetate inhibits the synthesis of the natural ligands of the androgen receptor, whereas enzalutamide directly inhibits the androgen receptor by several mechanisms. Abiraterone acetate and enzalutamide appear to be equally effective for patients with mCRPC pre- and postchemotherapy. Rational decision making for either one of these drugs is therefore potentially driven by individual patient characteristics. In this review, an overview of the pharmacokinetic characteristics is given for both drugs and potential and proven drug-drug interactions are presented. Additionally, the effect of patient-related factors on drug disposition are summarized and the limited data on the exposure-response relationships are described. The most important pharmacological feature of enzalutamide that needs to be recognized is its capacity to induce several key enzymes in drug metabolism. The potency to cause drug-drug interactions needs to be addressed in patients who are treated with multiple drugs simultaneously. Abiraterone has a much smaller drug-drug interaction potential; however, it is poorly absorbed, which is affected by food intake, and a large interpatient variability in drug exposure is observed. Dose reductions of abiraterone or, alternatively, the selection of enzalutamide, should be considered in patients with hepatic dysfunction. Understanding the pharmacological characteristics and challenges of both drugs could facilitate decision making for either one of the drugs.
Abstract: We present a case of a 77 year-old gentleman with previous coronary artery bypass grafting, admitted to hospital with recurrent torsades de pointes (TdP) due to abiraterone-induced hypokalaemia and prolonged QTc. The patient was on abiraterone and prednisone for metastatic prostate cancer. He required multiple defibrillations for recurrent TdP. Abiraterone is a relatively novel drug used in metastatic prostate cancer and we discuss this potential adverse effect and its management in this unusual presentation.
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: 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.