Cialis (Tadalafil) is used for treating erectile dysfunction in men (e.g., impotence). Comparing with Viagra, Cialis works in as quickly as 30 minutes and lasts for about 36 hours while Viagra effect lasts up to 5 hours.Besides, according to the scientific results, Cialis is not affected by food or beverages.



A generic drug is identical, or bioequivalent to a brand name drug in dosage form, safety, strength, route of administration, quality, performance characteristics and intended use. Although generic drugs are chemically identical to their branded counterparts, they are typically sold at substantial discounts from the branded price. According to the Congressional Budget Office, generic drugs save consumers an estimated $8 to $10 billion a year at retail pharmacies. Even more billions are saved when hospitals use generics.

Viagra (Sildenafil) is an oral drug for male impotence, also known as erectile dysfunction. Viagra has a great safety track record and proven effects that start acting in 30 minutes to 1 hour and last for about 4 hours.

New drugs, like other new products, are developed under patent protection. The patent protects the investment in the drug's development by giving the company the sole right to sell the drug while the patent is in effect. When patents or other periods of exclusivity expire, manufacturers can apply to the FDA to sell generic versions. The ANDA process does not require the drug sponsor to repeat costly animal and clinical research on ingredients or dosage forms already approved for safety and effectiveness. This applies to drugs first marketed after 1962.