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Interactions between Diltiazem and Orgovyx

1 drug interaction and 17 additional warnings found for the following 2 drugs:

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Drug interactions

Major drug interactions

Major:

dilTIAZem relugolix

Applies to: diltiazem and Orgovyx (relugolix)
Generally avoid

Coadministration with inhibitors of the P-glycoprotein (P-gp) efflux transporter may increase the plasma concentrations of relugolix, particularly when the inhibitors are given orally. Relugolix is a substrate for intestinal P-gp. In vitro, it is metabolized primarily by CYP450 3A and, to a lesser extent, by CYP450 2C8. When relugolix was coadministered with erythromycin, a combined P-gp and moderate CYP450 3A inhibitor, relugolix peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 6.2-fold. Increased exposure to relugolix may increase the risk and/or severity of adverse effects such as hot flushes; weight gain; decreased sex drive; erectile function difficulties; QT interval prolongation; musculoskeletal pain; constipation; diarrhea; increases in glucose, triglyceride, and liver transaminase levels; and decreased hemoglobin. No clinically significant differences in the pharmacokinetics of relugolix were observed when coadministered with voriconazole, a strong CYP450 3A inhibitor that does not inhibit P-gp.

Management

Concomitant use of relugolix with orally administered P-gp inhibitors should generally be avoided. If coadministration is required, the manufacturer recommends taking relugolix first and separating the dosing by at least 6 hours. Patients should be monitored more frequently for adverse effects. Alternatively, when relugolix is used as monotherapy for the treatment of prostate cancer, the prescribing information states that treatment with relugolix may be interrupted for up to two weeks if a short course of treatment with a P-gp inhibitor is necessary. Following interruption of relugolix for more than 7 days, the manufacturer recommends restarting therapy with a loading dose of 360 mg on the first day, then continuing with a dose of 120 mg once daily.

References (1)
  1. (2021) "Product Information. Orgovyx (relugolix)." Myovant Sciences, 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)
  1. Bailey DG, Arnold JMO, Spence JD (1994) "Grapefruit juice and drugs - how significant is the interaction." Clin Pharmacokinet, 26, p. 91-8
  2. 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
  3. Bailey DG, Malcolm J, Arnold O, Spence JD (1998) "Grapefruit juice-drug interactions." Br J Clin Pharmacol, 46, p. 101-10
  4. 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
  5. Cerner Multum, Inc. "UK Summary of Product Characteristics."
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)
  1. 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
  2. Moller IW (1987) "Cardiac arrest following intravenous verapamil combined with halothane anaesthesia." Br J Anaesth, 59, p. 522-6
  3. Oszko MA, Klutman NE (1987) "Use of calcium salts during cardiopulmonary resuscitation for reversing verapamil-associated hypotension." Clin Pharm, 6, p. 448-9
  4. 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
  5. 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
  6. Woie L, Storstein L (1981) "Successful treatment of suicidal verapamil poisoning with calcium gluconate." Eur Heart J, 2, p. 239-42
  7. Morris DL, Goldschlager N (1983) "Calcium infusion for reversal of adverse effects of intravenous verapamil." JAMA, 249, p. 3212-3
  8. 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
  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
  10. 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
  11. 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
  12. McMillan R (1988) "Management of acute severe verapamil intoxication." J Emerg Med, 6, p. 193-6
  13. Perkins CM (1978) "Serious verapamil poisoning: treatment with intravenous calcium gluconate." Br Med J, 2, p. 1127
  14. 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

15 potential interactions Applies to: 14 conditions, including Heart Failure, Heart Attack, Hypotension, Liver Disease, and Long QT Syndrome.

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.

Electrolyte Abnormalities

Moderate:

Orgovyx

The relugolix in Orgovyx has a moderate potential interaction with Electrolyte Abnormalities.

Androgen deprivation therapy may prolong the QT/QTc interval. Health care providers should consider if benefits of therapy outweigh the potential risks in patients with congenital long QT syndrome, congestive heart failure, electrolyte abnormalities, or taking other drugs that can also prolong the QT interval. Consider periodic monitoring of EKG and electrolytes.

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.

Moderate:

Orgovyx

The relugolix in Orgovyx has a moderate potential interaction with Heart Failure.

Androgen deprivation therapy may prolong the QT/QTc interval. Health care providers should consider if benefits of therapy outweigh the potential risks in patients with congenital long QT syndrome, congestive heart failure, electrolyte abnormalities, or taking other drugs that can also prolong the QT interval. Consider periodic monitoring of EKG and electrolytes.

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.

Long QT Syndrome

Moderate:

Orgovyx

The relugolix in Orgovyx has a moderate potential interaction with Long QT Syndrome.

Androgen deprivation therapy may prolong the QT/QTc interval. Health care providers should consider if benefits of therapy outweigh the potential risks in patients with congenital long QT syndrome, congestive heart failure, electrolyte abnormalities, or taking other drugs that can also prolong the QT interval. Consider periodic monitoring of EKG and electrolytes.

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.

Orgovyx

A total of 453 drugs are known to interact with Orgovyx.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor 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.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.