Drug Interactions between riociguat and vardenafil
This report displays the potential drug interactions for the following 2 drugs:
- riociguat
- vardenafil
Interactions between your drugs
vardenafil riociguat
Applies to: vardenafil and riociguat
CONTRAINDICATED: Coadministration of riociguat with phosphodiesterase (PDE) inhibitors may cause significant hypotension. The mechanism involves peripheral vasodilation secondary to enhanced levels of cyclic guanosine monophosphate (cGMP) in vascular smooth muscle cells. PDE inhibitors prevent degradation of cGMP, while riociguat promotes its synthesis by stimulating soluble guanylate cyclase (sGC), an enzyme in the cardiopulmonary system that binds with nitric oxide (NO) to catalyze the synthesis of cGMP. In 7 study patients with pulmonary arterial hypertension (PAH) on stable sildenafil treatment (20 mg three times a day), coadministration of single doses of riociguat (0.5 mg and 1 mg sequentially) demonstrated additive hemodynamic effects, but no pharmacodynamic advantages. A separate 12-week study in PAH patients (n=18) on stable sildenafil treatment (20 mg three times daily) compared the addition of riociguat (1 mg to 2.5 mg three times daily) to use of sildenafil alone. Compared with sildenafil alone, the standing systolic blood pressure of those on combination therapy was approximately 10 mmHg lower. In the long-term extension component of this study, concomitant use resulted in a high rate of discontinuation, primarily due to hypotension. Additionally, 3 deaths were reported; however, their relationship to the study drugs is unclear. Riociguat does not affect the pharmacokinetics of sildenafil.
MANAGEMENT: Concomitant use of riociguat with PDE inhibitors, including specific PDE-5 inhibitors (e.g., avanafil, sildenafil, tadalafil, vardenafil) or nonspecific PDE inhibitors (e.g., dipyridamole, theophylline), is considered contraindicated. When transitioning to riociguat from a PDE-5 inhibitor, or vice versa, patients should be monitored closely for signs and symptoms of hypotension. Riociguat should be discontinued at least 24 hours before administering a PDE-5 inhibitor. Likewise, avoidance of riociguat administration for 24 hours after sildenafil or 48 hours after tadalafil is recommended. Following treatment with tadalafil, a starting dose of 0.5 mg for riociguat may be beneficial for patients at risk of hypotension. Limited data exists for other PDE inhibitors and specific recommendations from the manufacturer of riociguat regarding timing separations for these inhibitors are not available. The package labeling of the PDE inhibitor in question and/or any relevant treatment guidelines or protocols should be consulted for more specific recommendations.
References (5)
- (2023) "Product Information. Adempas (riociguat)." Merck Sharp & Dohme (UK) Ltd
- Galie N, Muller K, Scalise AV, Grunig E (2015) "PATENT PLUS: a blinded, randomised and extension study of riociguat plus sildenafil in pulmonary arterial hypertension." Eur Respir J, 45, p. 1314-22
- (2022) "Product Information. Adempas (riociguat)." Bayer Australia Limited
- (2024) "Product Information. Sandoz Riociguat (riociguat)." Sandoz Canada Incorporated
- (2024) "Product Information. Adempas (riociguat)." Bayer Pharmaceutical Inc
Drug and food interactions
vardenafil food
Applies to: vardenafil
MONITOR: Grapefruit juice may increase the plasma concentrations of orally administered drugs that are substrates of the CYP450 3A4 isoenzyme. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Because grapefruit juice inhibits primarily intestinal rather than hepatic CYP450 3A4, the magnitude of interaction is greatest for those drugs that undergo significant presystemic metabolism by CYP450 3A4 (i.e., drugs with low oral bioavailability). 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. Pharmacokinetic interactions involving grapefruit juice are also subject to a high degree of interpatient variability, thus the extent to which a given patient may be affected is difficult to predict.
MANAGEMENT: Patients who regularly consume grapefruit or grapefruit juice should be monitored for adverse effects and altered plasma concentrations of drugs that undergo significant presystemic metabolism by CYP450 3A4. Grapefruit and grapefruit juice should be avoided if an interaction is suspected. Orange juice is not expected to interact with these drugs.
References (32)
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- Bailey DG, Arnold JMO, Spence JD (1994) "Grapefruit juice and drugs - how significant is the interaction." Clin Pharmacokinet, 26, p. 91-8
- Sigusch H, Hippius M, Henschel L, Kaufmann K, Hoffmann A (1994) "Influence of grapefruit juice on the pharmacokinetics of a slow release nifedipine formulation." Pharmazie, 49, p. 522-4
- Bailey DG, Arnold JM, Strong HA, Munoz C, Spence JD (1993) "Effect of grapefruit juice and naringin on nisoldipine pharmacokinetics." Clin Pharmacol Ther, 54, p. 589-94
- Yamreudeewong W, Henann NE, Fazio A, Lower DL, Cassidy TG (1995) "Drug-food interactions in clinical practice." J Fam Pract, 40, p. 376-84
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- Hukkinen SK, Varhe A, Olkkola KT, Neuvonen PJ (1995) "Plasma concentrations of triazolam are increased by concomitant ingestion of grapefruit juice." Clin Pharmacol Ther, 58, p. 127-31
- Min DI, Ku YM, Geraets DR, Lee HC (1996) "Effect of grapefruit juice on the pharmacokinetics and pharmacodynamics of quinidine in healthy volunteers." J Clin Pharmacol, 36, p. 469-76
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- Ozdemir M, Aktan Y, Boydag BS, Cingi MI, Musmul A (1998) "Interaction between grapefruit juice and diazepam in humans." Eur J Drug Metab Pharmacokinet, 23, p. 55-9
- Bailey DG, Malcolm J, Arnold O, Spence JD (1998) "Grapefruit juice-drug interactions." Br J Clin Pharmacol, 46, p. 101-10
- Bailey DG, Kreeft JH, Munoz C, Freeman DJ, Bend JR (1998) "Grapefruit juice felodipine interaction: Effect of naringin and 6',7'-dihydroxybergamottin in humans." Clin Pharmacol Ther, 64, p. 248-56
- Garg SK, Kumar N, Bhargava VK, Prabhakar SK (1998) "Effect of grapefruit juice on carbamazepine bioavailability in patients with epilepsy." Clin Pharmacol Ther, 64, p. 286-8
- Lilja JJ, Kivisto KT, Neuvonen PJ (1998) "Grapefruit juice-simvastatin interaction: Effect on serum concentrations of simvastatin, simvastatin acid, and HMG-CoA reductase inhibitors." Clin Pharmacol Ther, 64, p. 477-83
- Fuhr U, Maier-Bruggemann A, Blume H, et al. (1998) "Grapefruit juice increases oral nimodipine bioavailability." Int J Clin Pharmacol Ther, 36, p. 126-32
- Lilja JJ, Kivisto KT, Neuvonen PJ (1999) "Grapefruit juice increases serum concentrations of atorvastatin and has no effect on pravastatin." Clin Pharmacol Ther, 66, p. 118-27
- Eagling VA, Profit L, Back DJ (1999) "Inhibition of the CYP3A4-mediated metabolism and P-glycoprotein-mediated transport of the HIV-I protease inhibitor saquinavir by grapefruit juice components." Br J Clin Pharmacol, 48, p. 543-52
- Damkier P, Hansen LL, Brosen K (1999) "Effect of diclofenac, disulfiram, itraconazole, grapefruit juice and erythromycin on the pharmacokinetics of quinidine." Br J Clin Pharmacol, 48, p. 829-38
- Lee AJ, Chan WK, Harralson AF, Buffum J, Bui BCC (1999) "The effects of grapefruit juice on sertraline metabolism: An in vitro and in vivo study." Clin Ther, 21, p. 1890-9
- Dresser GK, Spence JD, Bailey DG (2000) "Pharmacokinetic-pharmacodynamic consequences and clinical relevance of cytochrome P450 3A4 inhibition." Clin Pharmacokinet, 38, p. 41-57
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- Takanaga H, Ohnishi A, Maatsuo H, et al. (2000) "Pharmacokinetic analysis of felodipine-grapefruit juice interaction based on an irreversible enzyme inhibition model." Br J Clin Pharmacol, 49, p. 49-58
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- Bailey DG, Dresser GR, Kreeft JH, Munoz C, Freeman DJ, Bend JR (2000) "Grapefruit-felodipine interaction: Effect of unprocessed fruit and probable active ingredients." Clin Pharmacol Ther, 68, p. 468-77
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- Flanagan D (2005) "Understanding the grapefruit-drug interaction." Gen Dent, 53, 282-5; quiz 286
riociguat food
Applies to: riociguat
ADJUST DOSE: Smoking may decrease the plasma concentrations of riociguat. The proposed mechanism is induction of the CYP450 1A1-mediated metabolism of riociguat by polycyclic aromatic hydrocarbons present in cigarette smoke. CYP450 1A1 is responsible for the formation of the major active metabolite, M1, which has just 1/3 to 1/10 the pharmacologic activity of riociguat. According to the product labeling, plasma concentrations of riociguat are reduced by 50% to 60% in smokers compared to nonsmokers.
MANAGEMENT: Patients should be advised to stop smoking. Riociguat dosages higher than 2.5 mg three times a day may be considered in cigarette smokers, if tolerated, to match the exposure seen in nonsmoking patients. However, safety and effectiveness of higher dosages have not been established. A dosage reduction should be considered in patients who stop smoking during treatment with riociguat. The tablet form of riociguat can generally be taken with or without food. Some authorities recommend not to switch between fed and fasted riociguat intake because of increased peak plasma levels of riociguat in the fasting compared to the fed state.
References (3)
- (2013) "Product Information. Adempas (riociguat)." Bayer Pharmaceutical Inc
- (2023) "Product Information. Adempas (riociguat)." Merck Sharp & Dohme (UK) Ltd
- (2014) "Product Information. Adempas (riociguat)." Bayer Australia Limited
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
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
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