Interaction between Dyphylline and Riociguat
Major
Others
| ID | DDInter613 and DDInter1600 |
| Interaction | 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, as 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. 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. Riociguat should be discontinued at least 24 hours before administering a PDE-5 inhibitor, and avoidance of riociguat administration within 24 hours after sildenafil or within 48 hours after tadalafil is recommended. Limited data exists for other PDE inhibitors. |
| References | |
| Alternative for Dyphylline |
R03D
|
| Alternative for Riociguat |
C02K
|
Potential Metabolism Interactions
Substrate-Substrate Interaction：If more than one drug is metabolized by the same CYP, it is possible that its metabolism is inhibited because of the competition between the drugs. That means, it can be useful to lower the dosage of the drugs in the drug-cocktail because they remain longer in the organism than in monotherapy.
Inhibitor-Inhibitor Interaction：Combining two or more inhibitors of one CYP, should be compensated by lowering the dosage of these drugs because the metabolism is reduced and the drugs remain longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.
Inhibitor-Substrate Interaction：Combining drugs that have inhibitory effect and are substrates of one particular CYP, should be compensated by lowering the dosage. They rest longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.