Drug Interactions between Aggrenox and riociguat

Using riociguat together with dipyridamole is not recommended. Combining these medications may significantly lower your blood pressure. You may be more likely to experience side effects such as dizziness, lightheadedness, fainting, flushing, headache, and nasal congestion. In some situations, your healthcare team may transition you from riociguat to a phosphodiesterase (PDE)-5 inhibitor (i.E., sildenafil, tadalafil) or vice versa to better treat your pulmonary arterial hypertension. If this occurs, you will need to stop the old medication for a period of time before starting the new medication. You may also require additional monitoring of your blood pressure during the transition. Be sure to discuss this and any other questions you have with your healthcare provider. Avoid driving or operating hazardous machinery until you know how these medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of riociguat with anticoagulant, antiplatelet, or other antithrombotic therapy may increase the risk of bleeding. Patients with pulmonary hypertension have an underlying risk for respiratory tract bleeding, which can be further exacerbated by riociguat and use of antithrombotic agents, particularly in the presence of additional risk factors such as recent episodes of serious hemoptysis (including those managed by bronchial arterial embolization) or concomitant prostacyclin use (e.g., epoprostenol, iloprost, and treprostinil) due to their inhibitory effect on platelet aggregation. In clinical trials, serious bleeding occurred in 2.4% and hemoptysis in 1% of patients taking riociguat compared to 0% of placebo patients. The proposed mechanism for the bleeding risk associated with riociguat is unknown. However, an in vitro study indicates that riociguat may inhibit von Willebrand factor elongation and platelet adhesion on the surface of pulmonary artery endothelial cells.

MANAGEMENT: Bleeding risk should be carefully evaluated before initiating riociguat in patients on antithrombotic therapy. Close clinical and laboratory monitoring for bleeding complications is recommended if concomitant use is required. Some authorities recommend avoiding riociguat in patients with a history of serious hemoptysis or who have previously undergone bronchial arterial embolization.