Viagra and sildenafil are effective treatment options for ED, but they both require a prescription. As a result, you cannot buy them over the counter (OTC) — they require a consultation with a ...

Vardenafil typically starts working faster, around 15 to 30 minutes after ingestion, while sildenafil may take ... know about ...

Before taking sildenafil, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In the United States, sildenafil for erectile dysfunction or pulmonary hypertension requires a prescription. The United Kingdom allows for over-the-counter (OTC) sales of the drug, in part to ...

4 Department of Paediatric Cardiology, University of Bristol, University Hospitals Bristol NHS Foundation Trust, Bristol, UK Correspondence to Dr Robert ... One of the potential agents for this ...