Avanafil (marketed as Stendra, commonly available in 100 mg) is a fast-acting PDE‑5 inhibitor used for erectile dysfunction. It can indeed cause dizziness, often related to its blood pressure–lowering effects. Avanafil relaxes blood vessels, which can lower blood pressure, particularly when standing up Dizziness commonly appears when the drug reaches peak effect—within 15–30 minutes after dosing, or even shortly after .
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