Viagra is used when treating male erection problems. Take it orally with a glass of water. The dose is usually taken 1 hour before sexual activity.

Cialis is used for the treatment of male erection problems. It is also currently undergoing Phase 3 of clinical trials for the treatment of pulmonary arterial hypertension.

Levitra is used for the treatment of men’s erection problems. It works faster than Sildenafil (Viagra®) and it has lower chance to cause visual disturbance side effect.

Viagra Professional is mostly used for the treatment of erectile dysfunction (impotency) for men and also for pulmonary arterial hypertension treatment.