QT time prolongation
Adverse drug events
Variants ✨For the computationally intensive evaluation of the variants, please choose the paid standard subscription.
Explanations of the substances for patients
We have no additional warnings for the combination of venlafaxine and asenapine. Please also consult the relevant specialist information.
The reported changes in exposure correspond to the changes in the plasma concentration-time curve [ AUC ]. We did not detect any change in exposure to venlafaxine. We currently cannot estimate the influence of asenapine. We do not expect any change in exposure for asenapine, when combined with venlafaxine (100%).
The pharmacokinetic parameters of the average population are used as the starting point for calculating the individual changes in exposure due to the interactions.
Venlafaxine has a mean oral bioavailability [ F ] of 45%, which is why the maximum plasma levels [Cmax] tend to change with an interaction. The terminal half-life [ t12 ] is rather short at 5.2 hours and constant plasma levels [ Css ] are reached quickly. The protein binding [ Pb ] is very weak at 27% and the volume of distribution [ Vd ] is very large at 236 liters, which is why, with a mean hepatic extraction rate of 0.42, both liver blood flow [Q] and a change in protein binding [Pb] are relevant. The metabolism takes place via CYP2C19, CYP2D6 and CYP3A4, among others and the active transport takes place in particular via PGP.
Asenapine has a low oral bioavailability [ F ] of 2%, which is why the maximum plasma level [Cmax] tends to change strongly with an interaction. The terminal half-life [ t12 ] is 24 hours and constant plasma levels [ Css ] are reached after approximately 96 hours. The protein binding [ Pb ] is moderately strong at 95% and the volume of distribution [ Vd ] is very large at 1700 liters. The metabolism mainly takes place via CYP1A2 and the active transport takes place in particular via UGT1A4.
|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: Venlafaxine 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, asenapine 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: Asenapine 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 knowledge, venlafaxine does not increase anticholinergic activity.
QT time prolongation
Rating: In combination, venlafaxine and asenapine can potentially trigger ventricular arrhythmias of the torsades de pointes type.
General adverse effects
|Side effects||∑ frequency||ven||ase|
|Weight gain||11.5 %||n.a.||11.5|
|Abnormal ejaculation||10.6 %||10.6||n.a.|
Akathisia (9.5%): asenapine
Tremor (5.6%): venlafaxine
Dream disorder: venlafaxine
Seizure: asenapine, venlafaxine
Neuroleptic malignant syndrome: asenapine, venlafaxine
Hyperglycemia (8.4%): asenapine
Hypertension (8%): venlafaxine
Orthostatic hypotension (1.5%): asenapine, venlafaxine
Blurred vision (5%): venlafaxine
Erectile dysfunction (4%): venlafaxine
Orgasm disorder (3.5%): venlafaxine
Suicidal (2.5%): asenapine, venlafaxine
Feeling nervous: venlafaxine
Loss of appetite: venlafaxine
Gastrointestinal hemorrhage: venlafaxine
Allergic skin reactions like pruritus and rash: venlafaxine
Hypersensitivity reaction: asenapine
Urinary retention: venlafaxine
Prolonged bleeding time: venlafaxine
Based on your answers and scientific information, we assess the individual risk of undesirable side effects. These recommendations are intended to advise professionals and are not a substitute for consultation with a doctor. In the restricted test version (alpha), the risk of all substances has not yet been conclusively assessed.
Abstract: Serotonin syndrome is a potentially fatal complication of serotonergic drug therapy. Usually, serotonin syndrome occurs with the concomitant use of two serotonergic drugs; this case report describes a patient with a classic presentation of serotonin syndrome induced solely by a venlafaxine overdose. Emergency physicians need to be aware that the serotonin syndrome may occur not only with serotonergic drug combinations but also with overdoses of a single potent serotonergic agent such as venlafaxine.
Abstract: The influence of cimetidine on the disposition pharmacokinetics of the antidepressant drug, venlafaxine, and its active metabolite, O-desmethylvenlafaxine, was examined in 18 healthy young men and women. The steady-state pharmacokinetic profiles of venlafaxine and O-desmethylvenlafaxine were evaluated during a 24-hour period after 5 days of treatment with venlafaxine (50 mg three times a day) and during a second 24-hour period after 5 days of combination treatment with venlafaxine (50 mg three times a day) and cimetidine (800 mg once a day). The apparent oral clearance of venlafaxine decreased significantly in the presence of cimetidine and the average steady-state plasma concentration of venlafaxine increased significantly in the presence of cimetidine, but there were no changes in the corresponding concentrations of the active metabolite. However, O-desmethylvenlafaxine exhibits pharmacologic activity that is approximately equimolar to that of venlafaxine, and the sum of venlafaxine plus O-desmethylvenlafaxine plasma concentrations was increased by an average of only 13%. Therefore, the effect of cimetidine coadministration is not expected to result in clinically important alterations in the response to venlafaxine in patients with depression. This may not be true, however, for patients with compromised hepatic metabolic function.
Abstract: CYP2D6 is involved in the O-demethylation metabolic pathway of venlafaxine in humans. In this study, we investigated whether this isozyme is stereoselective. Plasma samples from seven CYP2D6 extensive metabolizers (EMs) and five CYP2D6 poor metabolizers (PMs), collected during a period without and with coadministration of quinidine, were analysed. Subjects were administered venlafaxine hydrochloride 18.75 mg orally every 12 h for 48 h on two occasions (1 week apart); once alone and once during the concomitant administration of quinidine sulphate every 12 h. Blood and urine samples were collected under steady-state conditions over one dosing interval (12 h). The present results show that, although CYP2D6 catalyses the O-demethylation of both enantiomers of venlafaxine, it displays a marked stereoselectivity towards the (R)-enantiomer. The oral clearance of (R)-venlafaxine was found to be nine-fold higher in EMs compared to PMs [median (range) 173 (29-611) l/h versus 20 (16-24) l/h, P < 0.005], while it was two-fold higher for (S)-venlafaxine [73 (32-130) l/h versus 37 (21-44) l/h, P < 0.05]. In EMs, quinidine decreased (R)- and (S)-venlafaxine oral clearance by 12-fold ( 0.05) and four-fold ( 0.05), respectively. In contrast, quinidine did not have any effects on renal clearance of (R)-venlafaxine [4 (2-10) l/h for venlafaxine alone versus 5 (0.6-7) l/h for venlafaxine + quinidine] and of (S)-venlafaxine [4 (1-7) l/h for venlafaxine alone versus 3 (0.4-6) l/h for venlafaxine + quinidine]. The coadministration of quinidine to EMs resulted in an almost complete inhibition of the partial metabolic clearance of (R)-venlafaxine to O-demethylated metabolites [127 (10-493) l/h down to 1 (0.1-3) l/h, 0.05], while a seven-fold reduction was measured for (S)-venlafaxine [47 (14-94) l/h versus 7 (1-19) l/h, 0.05]. In PMs, coadministration of quinidine did not significantly change oral clearance and partial metabolic clearance of (R)- and (S)-venlafaxine to its various metabolites. In contrast, data obtained on the partial metabolic clearance of (R)- and (S)-venlafaxine to N-demethylated metabolites, a reaction which is mediated by CYP3A4, suggest a lack of stereoselectivity of this enzyme.
Abstract: OBJECTIVE: To report the case of a patient with serotonin syndrome induced by low-dose venlafaxine. CASE SUMMARY: A 29-year-old Taiwanese woman with major depressive disorder abruptly developed serotonin syndrome during low-dose (37.5 mg/d) venlafaxine monotherapy, with symptoms of restlessness, tremor, shivering, diarrhea, vomiting, ataxia, tachycardia, and myoclonus. The patient recovered in 2 hours after receiving prochlorperazine and lorazepam in the emergency department. Venlafaxine was discontinued, and she was discharged home. Two weeks later, the patient started to receive fluoxetine 20 mg/d and reported no adverse adverse effects during follow-up clinic visits. DISCUSSION: The clinical manifestations of this case meet Sternbach's criteria of serotonin syndrome. Its possible etiologic factors include panic attack, adverse drug reaction, pharmacodynamic interaction, and congenital absence of CYP2D6 enzyme activity. The Naranjo probability scale suggested a probable causality of venlafaxine treatment and serotonin syndrome. CONCLUSIONS: Clinicians should be aware of the risk of serotonin syndrome when the patient receives not only a combination of 2 antidepressants, but also the single potent serotonergic agent venlafaxine.
Abstract: OBJECTIVE: To study the influence of CYP3A4 inhibition by ketoconazole on the disposition of venlafaxine in individuals with different CYP2D6 pheno- and genotypes. METHODS: In an open two-phase study, 21 healthy volunteers with known CYP2D6 pheno- and genotype [14 extensive metabolisers (EMs), 7 poor metabolisers (PMs)] were given a single oral dose of venlafaxine (50 mg to EMs and 25 mg to PMs). Plasma and urine levels of venlafaxine and its three metabolites were measured and the pharmacokinetics of venlafaxine were determined. After a 2-week washout period, subjects were treated for 2 days with ketoconazole (100 mg twice daily) starting 1 day before the administration of venlafaxine; and the same parameters as for the administration of venlafaxine only were measured. RESULTS: Data were evaluated from 20 subjects (14 EMs and 6 PMs) who completed the study. The dose-corrected AUC of venlafaxine was on average 2.3 times higher ( P<0.01) and that of its active metabolite O-desmethylvenlafaxine 3.4 times lower ( P<0.0001) in PMs than EMs. There was a good correlation between the debrisoquine metabolic ratio and the ratio between the AUC of venlafaxine and that of O-desmethylvenlafaxine ( Rs=0.93, P<0.002). The majority of subjects showed higher plasma levels of venlafaxine and O-desmethylvenlafaxine upon co-administration of ketoconazole. AUC of venlafaxine significantly increased by 36% and that of O-desmethylvenlafaxine by 26% ( P<0.01). C(max) values increased by 32% and 18%, respectively. The elimination half-life of venlafaxine was unaltered. Three of the PMs displayed marked increases in AUC (81, 126 and 206%) and C(max) (60, 72, 119%) of venlafaxine while the other three showed small or no changes. CONCLUSIONS: Ketoconazole consistently affected the disposition of venlafaxine in EMs of debrisoquine while the response in PMs was erratic. The precise mechanisms underlying this interaction remain to be elucidated.
Abstract: This study investigated the effect of terbinafine and voriconazole on the pharmacokinetics of venlafaxine in healthy volunteers. Plasma concentrations of venlafaxine and O-desmethylvenlafaxine (ODV) were measured after ingestion of 75 mg venlafaxine without pretreatment (control), after terbinafine pretreatment, or after voriconazole pretreatment. During the terbinafine phase, the area under the plasma concentration-time curve (AUC(0-infinity)) of venlafaxine was on average 490% (P<0.001) and that of ODV 57% (P<0.001) of the corresponding control value. Terbinafine decreased the AUC(0-infinity) ratio of ODV over venlafaxine by 82% (P<0.001). Voriconazole slightly increased the sum of AUC(0-infinity) of venlafaxine plus AUC(0-infinity) of ODV (active moiety) by 31% (P<0.001). The most likely mechanism for the interaction between terbinafine and venlafaxine is the inhibition of CYP2D6-mediated O-demethylation of venlafaxine, whereas the minor effects of voriconazole are probably due to the inhibition of CYP3A4-, CYP2C9-, or CYP2C19-mediated metabolism of venlafaxine.
Abstract: An assessment of the effects of asenapine on QTc interval in patients with schizophrenia revealed a discrepancy between the results obtained by two different methods: an intersection-union test (IUT) (as recommended in the International Conference on Harmonisation E14 guidance) and an exposure-response (E-R) analysis. Simulations were performed in order to understand and reconcile this discrepancy. Although estimates of the time-matched, placebo-corrected mean change in QTc from baseline (ddQTc) at peak plasma concentrations from the E-R analysis ranged from 2 to 5 ms per dose level, the IUT applied to simulated data from the E-R model yielded maximum ddQTc estimates of 7-10 ms for the various doses of asenapine. These results indicate that the IUT can produce biased estimates that may induce a high false-positive rate in individual thorough QTc trials. In such cases, simulations from an E-R model can aid in reconciling the results from the two methods and may support the use of E-R results as a basis for labeling.
Abstract: The metabolism and excretion of asenapine [(3aRS,12bRS)-5-chloro-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenzo[2,3:6,7]-oxepino [4,5-c]pyrrole (2Z)-2-butenedioate (1:1)] were studied after sublingual administration of [(14)C]-asenapine to healthy male volunteers. Mean total excretion on the basis of the percent recovery of the total radioactive dose was ∼90%, with ∼50% appearing in urine and ∼40% excreted in feces; asenapine itself was detected only in feces. Metabolic profiles were determined in plasma, urine, and feces using high-performance liquid chromatography with radioactivity detection. Approximately 50% of drug-related material in human plasma was identified or quantified. The remaining circulating radioactivity corresponded to at least 15 very polar, minor peaks (mostly phase II products). Overall, >70% of circulating radioactivity was associated with conjugated metabolites. Major metabolic routes were direct glucuronidation and N-demethylation. The principal circulating metabolite was asenapine N(+)-glucuronide; other circulating metabolites were N-desmethylasenapine-N-carbamoyl-glucuronide, N-desmethylasenapine, and asenapine 11-O-sulfate. In addition to the parent compound, asenapine, the principal excretory metabolite was asenapine N(+)-glucuronide. Other excretory metabolites were N-desmethylasenapine-N-carbamoylglucuronide, 11-hydroxyasenapine followed by conjugation, 10,11-dihydroxy-N-desmethylasenapine, 10,11-dihydroxyasenapine followed by conjugation (several combinations of these routes were found) and N-formylasenapine in combination with several hydroxylations, and most probably asenapine N-oxide in combination with 10,11-hydroxylations followed by conjugations. In conclusion, asenapine was extensively and rapidly metabolized, resulting in several regio-isomeric hydroxylated and conjugated metabolites.
Abstract: BACKGROUND AND OBJECTIVE: The effects of hepatic or renal impairment on the pharmacokinetics of atypical antipsychotics are not well understood. Drug exposure may increase in patients with hepatic disease, owing to a reduction of certain metabolic enzymes. The objective of the present study was to study the effects of hepatic or renal impairment on the pharmacokinetics of asenapine and its N-desmethyl and N⁺-glucuronide metabolites. METHODS: Two clinical studies were performed to assess exposure to asenapine, desmethylasenapine and asenapine N⁺-glucuronide in subjects with hepatic or renal impairment. Pharmacokinetic parameters were determined from plasma concentration-time data, using standard noncompartmental methods. The pharmacokinetic variables that were studied included the maximum plasma concentration (C(max)) and the time to reach the maximum plasma concentration (t(max)). Eligible subjects, from inpatient and outpatient clinics, were aged ≥18 years with a body mass index of ≥18 kg/m² and ≤32 kg/m². Sublingual asenapine (Saphris®) was administered as a single 5 mg dose. RESULTS: Thirty subjects participated in the hepatic impairment study (normal hepatic function, n = 8; mild hepatic impairment [Child-Pugh class A], n = 8; moderate hepatic impairment [Child-Pugh class B], n = 8; severe hepatic impairment [Child-Pugh class C], n = 6). Thirty-three subjects were enrolled in the renal impairment study (normal renal function, n = 9; mild renal impairment, n = 8; moderate renal impairment, n = 8; severe renal impairment, n = 8). Asenapine and N-desmethylasenapine exposures were unaltered in subjects with mild or moderate hepatic impairment, compared with healthy controls. Severe hepatic impairment was associated with increased area under the plasma concentration-time curve from time zero to infinity (AUC(∞)) values for total asenapine, N-desmethylasenapine and asenapine N⁺-glucuronide (5-, 3-, and 2-fold, respectively), with slight increases in the C(max) of asenapine but 3- and 2-fold decreases in the C(max) values for N-desmethylasenapine and asenapine N⁺-glucuronide, respectively, compared with healthy controls. The mean AUC(∞) of unbound asenapine was more than 7-fold higher in subjects with severe hepatic impairment than in healthy controls. Mild renal impairment was associated with slight elevations in the AUC(∞) of asenapine compared with healthy controls; alterations observed with moderate and severe renal impairment were marginal. N-desmethylasenapine exposure was only slightly altered by renal impairment. No correlations were observed between exposure and creatinine clearance. CONCLUSION: Severe hepatic impairment (Child-Pugh class C) was associated with pronounced increases in asenapine exposure, but significant increases were not seen with mild (Child-Pugh class A) or moderate (Child-Pugh class B) hepatic impairment, or with any degree of renal impairment. Asenapine is not recommended in patients with severe hepatic impairment; no dose adjustment is needed in patients with mild or moderate hepatic impairment, or in patients with renal impairment.
Abstract: INTRODUCTION: Many psychotropic drugs can delay cardiac repolarization and thereby prolong the rate-corrected QT interval (QTc). A prolonged QTc often arouses concern in clinical practice, as it can be followed, in rare cases, by the life-threatening polymorphic ventricular tachyarrhythmia called torsade de pointes (TdP). METHOD: We searched PubMed for pertinent literature on the risk of QTc prolongation and/or TdP associated with commonly used psychotropic drugs. RESULTS: Thioridazine and ziprasidone confer the highest risk of QTc prolongation and/or TdP. There is also a clinically significant risk associated with haloperidol given intravenously in high doses. TdP has been reported in a few cases in association with the use of newer antipsychotic drugs (mainly quetiapine and amisulpride), most of the tri- and tetracyclic antidepressants, and the selective monoamine reuptake inhibitors citalopram, fluoxetine, paroxetine, and venlafaxine. As a rule, however, QTc prolongation and/or TdP occur only in the presence of multiple additional risk factors, such as age over 65 years, pre-existing cardiovascular disease, bradycardia, female sex, hypokalemia, hypomagnesemia, a supratherapeutic or toxic serum concentration, or the simultaneous administration of other drugs that delay repolarization or interfere with drug metabolism. CONCLUSION: Before prescribing a psychotropic drug, the physician should carefully assess its risks and benefits to avoid this type of adverse reaction, particularly when additional risk factors are present. The ECG and electrolytes should be regularly monitored in patients taking psychotropic drugs.
Abstract: BACKGROUND: Anticholinergic drugs are often involved in explicit criteria for inappropriate prescribing in older adults. Several scales were developed for screening of anticholinergic drugs and estimation of the anticholinergic burden. However, variation exists in scale development, in the selection of anticholinergic drugs, and the evaluation of their anticholinergic load. This study aims to systematically review existing anticholinergic risk scales, and to develop a uniform list of anticholinergic drugs differentiating for anticholinergic potency. METHODS: We performed a systematic search in MEDLINE. Studies were included if provided (1) a finite list of anticholinergic drugs; (2) a grading score of anticholinergic potency and, (3) a validation in a clinical or experimental setting. We listed anticholinergic drugs for which there was agreement in the different scales. In case of discrepancies between scores we used a reputed reference source (Martindale: The Complete Drug Reference®) to take a final decision about the anticholinergic activity of the drug. RESULTS: We included seven risk scales, and evaluated 225 different drugs. Hundred drugs were listed as having clinically relevant anticholinergic properties (47 high potency and 53 low potency), to be included in screening software for anticholinergic burden. CONCLUSION: Considerable variation exists among anticholinergic risk scales, in terms of selection of specific drugs, as well as of grading of anticholinergic potency. Our selection of 100 drugs with clinically relevant anticholinergic properties needs to be supplemented with validated information on dosing and route of administration for a full estimation of the anticholinergic burden in poly-medicated older adults.
Abstract: No Abstract available
Abstract: No Abstract available
Abstract: This is the second report of a patient developing severe prolongation of QTc interval with a dose of 300mg/day of venlafaxine; on stopping it, QTc reverted to normalcy. Venlafaxine was restarted and maintained at 150mg/day, with QTc interval remaining normal, indicating, that it has a dose-dependent effect on QTc interval. Venlafaxine was not changed as she had responded best to this drug compared to any other antidepressant. Over 20 years, the only time she had a period of 5 years of remission, was when she was on 75mg of venlafaxine/day.
Abstract: The potential of inhibitory metabolites of perpetrator drugs to contribute to drug-drug interactions (DDIs) is uncommon and underestimated. However, the occurrence of unexpected DDI suggests the potential contribution of metabolites to the observed DDI. The aim of this study was to develop a physiologically-based pharmacokinetic (PBPK) model for bupropion and its three primary metabolites-hydroxybupropion, threohydrobupropion and erythrohydrobupropion-based on a mixed "bottom-up" and "top-down" approach and to contribute to the understanding of the involvement and impact of inhibitory metabolites for DDIs observed in the clinic. PK profiles from clinical researches of different dosages were used to verify the bupropion model. Reasonable PK profiles of bupropion and its metabolites were captured in the PBPK model. Confidence in the DDI prediction involving bupropion and co-administered CYP2D6 substrates could be maximized. The predicted maximum concentration (C) area under the concentration-time curve (AUC) values and Cand AUC ratios were consistent with clinically observed data. The addition of the inhibitory metabolites into the PBPK model resulted in a more accurate prediction of DDIs (AUC and Cratio) than that which only considered parent drug (bupropion) P450 inhibition. The simulation suggests that bupropion and its metabolites contribute to the DDI between bupropion and CYP2D6 substrates. The inhibitory potency from strong to weak is hydroxybupropion, threohydrobupropion, erythrohydrobupropion, and bupropion, respectively. The present bupropion PBPK model can be useful for predicting inhibition from bupropion in other clinical studies. This study highlights the need for caution and dosage adjustment when combining bupropion with medications metabolized by CYP2D6. It also demonstrates the feasibility of applying the PBPK approach to predict the DDI potential of drugs undergoing complex metabolism, especially in the DDI involving inhibitory metabolites.
Abstract: Asenapine is one of the newer atypical antipsychotics on the market. It is a sublingually administered drug that is indicated for the treatment of both schizophrenia and bipolar disorder, and is considered to be safe and well tolerated. Herein, we report a 71-year-old female with a history of bipolar disorder who had ventricular trigemini and experienced a large increase in her QTc interval after starting treatment with asenapine. These changes ceased following withdrawal of asenapine. In this case report, we discuss the importance of cardiac monitoring when switching antipsychotics, even to those that are considered to have low cardiac risk.
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: A highly selective and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been described for the determination of asenapine (ASE) in presence of its inactive metabolites-desmethyl asenapine (DMA) and asenapine--glucuronide (ASG). ASE, and ASE 13C-d3, used as internal standard (IS), were extracted from 300 µL human plasma by a simple and precise liquid-liquid extraction procedure using methyl-butyl ether. Baseline separation of ASE from its inactive metabolites was achieved on Chromolith Performance RP(100 mm × 4.6 mm) column using acetonitrile-5.0 mM ammonium acetate-10% formic acid (90:10:0.1, v/v/v) within 4.5 min. Quantitation of ASE was done on a triple quadrupole mass spectrometer equipped with electrospray ionization in the positive mode. The protonated precursor to product ion transitions monitored for ASE and ASE 13C-d3 were286.1 → 166.0 and290.0 → 166.1, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) of the method were 0.0025 ng/mL and 0.050 ng/mL respectively in a linear concentration range of 0.050-20.0 ng/mL for ASE. The intra-batch and inter-batch precision (% CV) and mean relative recovery across quality control levels were ≤ 5.8% and 87.3%, respectively. Matrix effect, evaluated as IS-normalized matrix factor, ranged from 1.03 to 1.05. The stability of ASE under different storage conditions was ascertained in presence of the metabolites. The developed method is much simpler, matrix free, rapid and economical compared to the existing methods. The method was successfully used for a bioequivalence study of asenapine in healthy Indian subjects for the first time.