These medicines are called PDE5 inhibitors. Maintaining Proper Dosage and Frequency To ensure optimal results, it’s essential to follow the prescribed dosage and frequency guidelines provided by your doctor. Generic viagra can be purchased online from reputable pharmacies. Related Content. On the other hand, if your doctor recommends daily use based on your condition, this option ensures readiness whenever desired.In fact, in some countries, generic Viagra is available without a prescription, making it even more accessible to those in need. Generic viagra is available in various strengths, including 25mg, 50mg, and mg. Generic viagra has been found to be effective in approximately % of men with ED. AdGet a Prescription for ED treatment, discreetly deliverED to your ive Offers · How It Works · Get More Info4/5 ( reviews)Types: Tadalafil · Finasteride · Sildenafil. (Sildenafil is the active drug in Viagra.) If these drugs are available without a prescription, that means that they haven’t been tested or approved by the FDA.