Riociguat and Tadalafil interaction
Riociguat and Tadalafil: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Riociguat (Adempas) label · effective 2026-08-13
Do not administer 24 hours before or within 48 hours after tadalafil.
Do not administer 24 hours before or within 48 hours after tadalafil [see Dosage and Administration (2.6) ].
Phosphodiesterase Inhibitors Concomitant administration of Adempas with specific PDE-5 inhibitors (such as sildenafil, tadalafil, or vardenafil) or nonspecific PDE-5 inhibitors (such as dipyridamole or theophylline) is contraindicated [see Dosage and Administration (2.6), Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.2 )].
PDE Inhibitors: Co-administration of Adempas with specific PDE-5 inhibitors (such as sildenafil, tadalafil, or vardenafil) and nonspecific PDE inhibitors (such as dipyridamole or theophylline), is contraindicated because of hypotension.
Clinical experience with co-administration of Adempas and other phosphodiesterase inhibitors (for example, milrinone, cilostazole, roflumilast) is limited.
From the Tadalafil (Cialis) label · effective 2026-06-03
Administration with guanylate cyclase (GC) stimulators, such as riociguat ( 4.3 ).
Concomitant Guanylate Cyclase (GC) Stimulators Do not use CIALIS in patients who are using a GC stimulator, such as riociguat.
When vasodilators are used in combination, an additive effect on blood pressure may be anticipated.
When mild vasodilators are taken in combination, blood-pressure-lowering effects of each individual compound may be increased.
Patients with left ventricular outflow obstruction, (e.g., aortic stenosis and idiopathic hypertrophic subaortic stenosis) can be sensitive to the action of vasodilators, including PDE5 inhibitors.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.