Interactions between Diltiazem and Larotrectinib
1 drug interaction and 16 additional warnings found for the following 2 drugs:
- diltiazem
- larotrectinib
Drug interactions
Moderate drug interactions
Moderate:
dilTIAZem larotrectinib
Applies to: diltiazem and larotrectinib
Monitor
Coadministration with inhibitors of CYP450 3A4, P-glycoprotein (P-gp), and/or breast cancer resistance protein (BCRP) may increase the plasma concentrations of larotrectinib. According to the prescribing information, larotrectinib is metabolized primarily by the CYP450 3A4 isoenzyme and is a substrate of the P-gp and BCRP efflux transporters in vitro. When a single 100 mg dose of larotrectinib was coadministered with itraconazole (200 mg once daily for 7 days), a potent CYP450 3A4 inhibitor and P-gp/BCRP inhibitor, larotrectinib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 2.8- and 4.3-fold, respectively, compared to administration of larotrectinib alone. When a single 100 mg dose of larotrectinib was administered in healthy adult subjects with a single 600 mg dose of rifampin (a P-gp and BCRP inhibitor during initial use, but an inducer of CYP450 3A4 and P-gp following chronic use), larotrectinib Cmax and AUC increased by 1.8- and 1.7-fold, respectively. Coadministration with fluconazole, a moderate CYP450 3A4 inhibitor, is predicted to increase larotrectinib steady-state Cmax by 1.9-fold and AUC by 2.7-fold.
Management
Caution is advised when larotrectinib is used with CYP450 3A4, P-gp, and/or BCRP inhibitors. Patients should be monitored more frequently for adverse effects such as neurotoxicity (delirium, dysarthria, dizziness, gait disturbance, paraesthesia, encephalopathy, memory impairment, tremor) and hepatotoxicity (elevations in liver transaminases), and the larotrectinib dosage adjusted based on severity of emergent adverse reactions in accordance with the product labeling.
References (3)
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- Cerner Multum, Inc. "Australian Product Information."
- (2022) "Product Information. Vitrakvi (larotrectinib)." Bayer Pharmaceutical Inc
Food/lifestyle interactions
Moderate food/lifestyle interactions
Moderate:
dilTIAZem Food/Lifestyle
Applies to: diltiazem
Monitor
Like many CNS-active agents, alcohol can exhibit hypotensive effects. Coadministration with antihypertensive agents including diltiazem may result in additive effects on blood pressure and orthostasis.
Monitor
Grapefruit juice may increase the plasma concentrations of orally administered diltiazem in some patients. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In a study of ten healthy male volunteers, administration of a single 120 mg oral dose of immediate-release diltiazem in combination with 250 mL of grapefruit juice increased the diltiazem peak plasma concentration (Cmax) and systemic exposure (AUC) by an average of 22% and 20%, respectively, compared to administration with water. The time to reach Cmax (Tmax) and the terminal half-life were not affected, and no statistically significant differences in blood pressure and heart rate were observed during administration with grapefruit juice relative to water. In a different study, repeated administration of 200 mL of grapefruit juice at 0, 2, 4, 8 and 12 hours had no significant effect on the Cmax or AUC of a single 120 mg oral dose of diltiazem, but increased its half-life from 4.1 to 5.1 hours. The ratios for the N-demethyl and deacetyl metabolites to diltiazem were also not affected by grapefruit juice. However, because pharmacokinetic interactions involving grapefruit juice are often subject to a high degree of interpatient variability, the extent to which a given patient may be affected is difficult to predict.
Management
Patients should be advised that alcohol may potentiate the hypotensive effects of diltiazem, especially during the initiation of therapy and following a dosage increase. Caution should be exercised when rising from a sitting or recumbent position, and patients should notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia. Patients who regularly consume grapefruit or grapefruit juice should be monitored for increased adverse effects of diltiazem such as such as headache, irregular heartbeat, edema, unexplained weight gain, and chest pain. Grapefruit and grapefruit juice should be avoided if an interaction is suspected.
References (5)
- Bailey DG, Arnold JMO, Spence JD (1994) "Grapefruit juice and drugs - how significant is the interaction." Clin Pharmacokinet, 26, p. 91-8
- Sigusch H, Henschel L, Kraul H, Merkel U, Hoffmann A (1994) "Lack of effect of grapefruit juice on diltiazem bioavailability in normal subjects." Pharmazie, 49, p. 675-9
- Bailey DG, Malcolm J, Arnold O, Spence JD (1998) "Grapefruit juice-drug interactions." Br J Clin Pharmacol, 46, p. 101-10
- Christensen H, Asberg A, Holmboe AB, Berg KJ (2002) "Coadministration of grapefruit juice increases systemic exposure of diltiazem in healthy volunteers." Eur J Clin Pharmacol, 58, p. 515-520
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
Moderate:
larotrectinib Food/Lifestyle
Applies to: larotrectinib
Generally avoid
Grapefruit juice may increase the plasma concentrations of larotrectinib. The proposed mechanism is inhibition of CYP450 3A4-mediated metabolism of larotrectinib by certain compounds present in grapefruit. When a single 100 mg dose of larotrectinib was coadministered with itraconazole, a potent CYP450 3A4 inhibitor, larotrectinib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 2.8- and 4.3-fold, respectively, compared to administration of larotrectinib alone. The interaction has not been studied with grapefruit juice. In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Increased exposure to larotrectinib may increase the risk of adverse effects such as neurotoxicity (delirium, dysarthria, dizziness, gait disturbance, paraesthesia, encephalopathy, memory impairment, tremor) and hepatotoxicity (elevations in liver transaminases). Food does not alter the pharmacokinetics of larotrectinib to a clinically significant extent. When a single 100 mg dose of larotrectinib was administered with a high-fat meal (approximately 900 calories; 58 g carbohydrate, 56 g fat, 43 g protein) in healthy study subjects, larotrectinib peak plasma concentration (Cmax) was reduced by 35% while systemic exposure (AUC) was similar compared to administration in the fasted state.
Management
Larotrectinib may be taken with or without food. Patients should avoid the consumption of grapefruit and grapefruit juice during treatment.
References (1)
- (2018) "Product Information. Vitrakvi (larotrectinib)." Bayer Pharmaceutical Inc
Moderate:
dilTIAZem multivitamins with minerals
Applies to: diltiazem
Monitor
Calcium-containing products may decrease the effectiveness of calcium channel blockers by saturating calcium channels with calcium. Calcium chloride has been used to manage acute severe verapamil toxicity.
Management
Management consists of monitoring the effectiveness of calcium channel blocker therapy during coadministration with calcium products.
References (14)
- Henry M, Kay MM, Viccellio P (1985) "Cardiogenic shock associated with calcium-channel and beta blockers: reversal with intravenous calcium chloride." Am J Emerg Med, 3, p. 334-6
- Moller IW (1987) "Cardiac arrest following intravenous verapamil combined with halothane anaesthesia." Br J Anaesth, 59, p. 522-6
- Oszko MA, Klutman NE (1987) "Use of calcium salts during cardiopulmonary resuscitation for reversing verapamil-associated hypotension." Clin Pharm, 6, p. 448-9
- Schoen MD, Parker RB, Hoon TJ, et al. (1991) "Evaluation of the pharmacokinetics and electrocardiographic effects of intravenous verapamil with intravenous calcium chloride pretreatment in normal subjects." Am J Cardiol, 67, p. 300-4
- O'Quinn SV, Wohns DH, Clarke S, Koch G, Patterson JH, Adams KF (1990) "Influence of calcium on the hemodynamic and anti-ischemic effects of nifedipine observed during treadmill exercise testing." Pharmacotherapy, 10, p. 247
- Woie L, Storstein L (1981) "Successful treatment of suicidal verapamil poisoning with calcium gluconate." Eur Heart J, 2, p. 239-42
- Morris DL, Goldschlager N (1983) "Calcium infusion for reversal of adverse effects of intravenous verapamil." JAMA, 249, p. 3212-3
- Guadagnino V, Greengart A, Hollander G, Solar M, Shani J, Lichstein E (1987) "Treatment of severe left ventricular dysfunction with calcium chloride in patients receiving verapamil." J Clin Pharmacol, 27, p. 407-9
- Luscher TF, Noll G, Sturmer T, Huser B, Wenk M (1994) "Calcium gluconate in severe verapamil intoxication." N Engl J Med, 330, p. 718-20
- Bar-Or D, Gasiel Y (1981) "Calcium and calciferol antagonise effect of verapamil in atrial fibrillation." Br Med J (Clin Res Ed), 282, p. 1585-6
- Lipman J, Jardine I, Roos C, Dreosti L (1982) "Intravenous calcium chloride as an antidote to verapamil-induced hypotension." Intensive Care Med, 8, p. 55-7
- McMillan R (1988) "Management of acute severe verapamil intoxication." J Emerg Med, 6, p. 193-6
- Perkins CM (1978) "Serious verapamil poisoning: treatment with intravenous calcium gluconate." Br Med J, 2, p. 1127
- Moroni F, Mannaioni PF, Dolara A, Ciaccheri M (1980) "Calcium gluconate and hypertonic sodium chloride in a case of massive verapamil poisoning." Clin Toxicol, 17, p. 395-400
Disease interactions
13 potential interactions Applies to: 12 conditions, including Heart Failure, Heart Attack, Hypotension, Liver Disease, and Ventricular Arrhythmia.
Aortic Stenosis
Major:
diltiazem
dilTIAZem has a major potential interaction with Aortic Stenosis.
The use of some calcium channel blockers (CCBs) is contraindicated in patients with advanced aortic stenosis. CCBs whose pharmacologic effect is partially dependent on their ability to reduce afterload (e.g., diltiazem, nicardipine, nifedipine, verapamil) may be of less benefit in these patients due to a fixed impedance to flow across the aortic valve and may, in fact, worsen rather than improve myocardial oxygen balance. Rarely, heart failure has developed following the initiation of these CCBs, particularly in patients receiving concomitant beta-blocker therapy.
Cardiogenic Shock
Major:
diltiazem
dilTIAZem has a major potential interaction with Cardiogenic Shock.
In general, calcium channel blockers (CCBs) should not be used in patients with hypotension (systolic pressure < 90 mm Hg) or cardiogenic shock. Due to potential negative inotropic and peripheral vasodilating effects, the use of CCBs may further depress cardiac output and blood pressure, which can be detrimental in these patients. The use of verapamil and diltiazem is specifically contraindicated under these circumstances.
Heart Attack
Major:
diltiazem
dilTIAZem has a major potential interaction with Heart Attack.
Diltiazem has demonstrated a negative inotropic effect in isolated animal tissue preparations but rarely in clinical situations. Hemodynamic studies in humans with normal ventricular function and in patients with a compromised myocardium have not shown a reduction in cardiac index nor consistent negative effects on contractility. However, worsening of congestive heart failure has been reported in patients with preexisting impairment of ventricular function. Therapy with diltiazem should be administered cautiously, if at all, in patients with severe left ventricular dysfunction (e.g., ejection fraction < 30%) or moderate to severe symptoms of cardiac failure and in patients with any degree of ventricular dysfunction if they are receiving a beta-adrenergic blocker. Likewise, diltiazem should not be given to patients with acute myocardial infarction and pulmonary congestion documented by X-ray on admission, since associated heart failure may be acutely worsened. Mild symptoms of cardiac failure should be under control, if possible, prior to initiating diltiazem therapy.
Heart Block
Major:
diltiazem
dilTIAZem has a major potential interaction with Heart Block.
The use of some calcium channel blockers (CCBs) is contraindicated in patients with severe bradyarrhythmia, sick sinus syndrome (unless a functioning pacemaker is present), or heart block greater than the first degree (unless a functioning pacemaker is present). CCBs like bepridil, diltiazem and verapamil have a negative effect on AV conduction and the SA node and may exacerbate these conditions.
Heart Failure
Major:
diltiazem
dilTIAZem has a major potential interaction with Heart Failure.
Diltiazem has demonstrated a negative inotropic effect in isolated animal tissue preparations but rarely in clinical situations. Hemodynamic studies in humans with normal ventricular function and in patients with a compromised myocardium have not shown a reduction in cardiac index nor consistent negative effects on contractility. However, worsening of congestive heart failure has been reported in patients with preexisting impairment of ventricular function. Therapy with diltiazem should be administered cautiously, if at all, in patients with severe left ventricular dysfunction (e.g., ejection fraction < 30%) or moderate to severe symptoms of cardiac failure and in patients with any degree of ventricular dysfunction if they are receiving a beta-adrenergic blocker. Likewise, diltiazem should not be given to patients with acute myocardial infarction and pulmonary congestion documented by X-ray on admission, since associated heart failure may be acutely worsened. Mild symptoms of cardiac failure should be under control, if possible, prior to initiating diltiazem therapy.
Hypotension
Major:
diltiazem
dilTIAZem has a major potential interaction with Hypotension.
In general, calcium channel blockers (CCBs) should not be used in patients with hypotension (systolic pressure < 90 mm Hg) or cardiogenic shock. Due to potential negative inotropic and peripheral vasodilating effects, the use of CCBs may further depress cardiac output and blood pressure, which can be detrimental in these patients. The use of verapamil and diltiazem is specifically contraindicated under these circumstances.
Ischemic Heart Disease
Major:
diltiazem
dilTIAZem has a major potential interaction with Ischemic Heart Disease.
Increased frequency, duration, and/or severity of angina, as well as acute myocardial infarction, have rarely developed during initiation or dosage increase of calcium channel blockers (CCBs), particularly in patients with severe obstructive coronary artery disease and those treated with immediate-release formulations. The mechanism of this effect is not established. Therapy with CCBs should be administered cautiously in patients with significant coronary artery disease.
Liver Disease
Major:
diltiazem
dilTIAZem has a major potential interaction with Liver Disease.
Calcium channel blockers (CCBs) are extensively metabolized by the liver. The half-lives of CCBs may be prolonged substantially in patients with severe hepatic impairment, with the potential for significant drug accumulation. In addition, the use of some CCBs has been associated with elevations in serum transaminases, both with and without concomitant elevations in alkaline phosphatase and bilirubin. While these effects may be transient and reversible, some patients have developed cholestasis or hepatocellular injury. Therapy with CCBs should be administered cautiously and often at reduced dosages in patients with significantly impaired hepatic function. Periodic monitoring of liver function is advised.
Moderate:
larotrectinib
Larotrectinib has a moderate potential interaction with Liver Disease.
Forty- five percent of the patients receiving larotrectinib had increased hepatic parameters, including Grade 3 increased AST or ALT in 6% of patients. Monitor liver tests, including ALT and AST, every 2 weeks during the first month of treatment, then monthly thereafter, and as clinically indicated. Treatment should be withheld or permanently discontinued based on the severity of hepatic toxicity. Caution is advised in patients with moderate to severe hepatic impairment as the drug clearance was reduced in these patients (Child-Pugh B and C). Dose should be reduced on these patients as recommended by the manufacturers (refer to prescribing information).
Preexcitation Syndrome
Major:
diltiazem
dilTIAZem has a major potential interaction with Preexcitation Syndrome.
The use of intravenous diltiazem is contraindicated for the management of atrial flutter or fibrillation in patients with an accessory AV tract (e.g., those with Wolff-Parkinson-White or Lown-Ganong-Levine syndrome). Diltiazem can cause ventricular fibrillation and cardiac arrest in such patients, the mechanism of which is related to the drug's ability to shorten the refractory period and accelerate antegrade conduction within the accessory pathway.
Renal Dysfunction
Moderate:
diltiazem
dilTIAZem has a moderate potential interaction with Renal Dysfunction.
Diltiazem is extensively metabolized by the liver and subsequently excreted in the urine, primarily as metabolites. Limited data suggest that the pharmacokinetic disposition of diltiazem is not altered in the presence of renal insufficiency or even end-stage renal disease. However, the effects of possible metabolite accumulation have not been studied. The manufacturers recommend that therapy with diltiazem be administered cautiously in patients with impaired renal function. Laboratory parameters of renal function should be monitored at regular intervals.
Sinus Node Dysfunction
Major:
diltiazem
dilTIAZem has a major potential interaction with Sinus Node Dysfunction.
The use of some calcium channel blockers (CCBs) is contraindicated in patients with severe bradyarrhythmia, sick sinus syndrome (unless a functioning pacemaker is present), or heart block greater than the first degree (unless a functioning pacemaker is present). CCBs like bepridil, diltiazem and verapamil have a negative effect on AV conduction and the SA node and may exacerbate these conditions.
Ventricular Arrhythmia
Major:
diltiazem
dilTIAZem has a major potential interaction with Ventricular Arrhythmia.
The use of intravenous diltiazem or verapamil is contraindicated in patients with ventricular tachycardia. IV administration of a calcium channel blocker can precipitate cardiac arrest in such patients. Marked hemodynamic deterioration and ventricular fibrillation have occurred in patients with wide-complex ventricular tachycardia (QRS >= 0.12 seconds) treated with IV verapamil.
More resources
diltiazem
A total of 771 drugs are known to interact with diltiazem.
- Diltiazem is in the following drug classes: calcium channel blockers, group IV antiarrhythmics.
- Diltiazem is used to treat the following conditions:
larotrectinib
A total of 536 drugs are known to interact with larotrectinib.
- Larotrectinib is in the drug class multikinase inhibitors.
- Larotrectinib is used to treat Solid Tumors.
Drug Interaction Classification
| Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
| Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
| Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
| No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.