Viagra vs Cialis

Viagra was patented in 1993 by Pfizer, and Cialis was patented only in 2002 by Lilly ICOS. Both drugs received FDA approval as effective medications for erectile dysfunction (ED) treatment. Due to its successful promotional campaign, Viagra is more popular than Cialis, however, the latter has become widely known within the past several years. Besides, Viagra and Cialis differ in durability, price and some side effects.

Advantages of Viagra

The main advantage of Viagra over Cialis is that this brand is famous all over the world and has a well-earned reputation. People who don't know anything about ED medications are more likely to choose Viagra, because these pills seem reliable already, and much related information is available to learn all the details. Approved by FDA in 1998, Viagra was the first orally administered drug for male impotency treatment. Viagra's price is its another benefit. All in all, usually Viagra is cheaper and more available than Cialis.

Advantages of Cialis

However, Cialis has its incontestable advantage over Viagra, and that is the durability of action. While Viagra helps men to achieve and maintain erection during 5 hours or so, Cialis is effective during up to 36 hours. The “weekend pill” allows to stay sexually active literally for days, while with Viagra one can have erection only for several hours. So, considering effectiveness, Cialis is more preferable than Viagra.

Name	Viagra	Cialis
Generic name	Sildenafil Citrate	Tadalafil
Manufacturer	Pfizer	Eli Lilly and ICOS
FDA approved	March 27, 1998	November 1, 2003
Available dosage	25 mg, 50 mg and 100 mg tablets	5 mg, 10 mg and 20 mg tablets
Duration of effects	approximately 4 hours	approximately 17 to 36 hours
Maximum doses	100 mg a day	20 mg a day
How to take	Without food	Without food
When to take	30 to 60 minutes before sexual activity	30 to 60 minutes before sexual activity
Side effects	Headache, flushing, indigestion, stuffy or runny nose, upset stomach, diarrhea	Headache, flushing, indigestion, stuffy or runny nose, upset stomach, dizziness
Warnings	Do not take with nitrates (Nitro-Dur, others), or if you have certain heart valve problems. Should be used with caution or not used at all with alpha blockers. Should not be used with some antibiotic, antiviral or antifungal medications.	Do not take with nitrates (Nitro-Dur, others) or alpha blockers (Hytrin, Cardura, others), or if you have certain heart valve problems. Should be used with caution or not used at all with alpha blockers. Should not be used with some antibiotic, antiviral or antifungal medications.
Shelf life	2 years	3 years
Special conditions	Sexual stimulation	Sexual stimulation