Generic Viagra Meds
Viagra is a prescription drug meant to treat male erectile dysfunction. It was introduced into the market in 1998 by Pfizer pharmaceutical company but it had had a long and complicated history before a consumer could find it sold in any average pharmacy. Viagra sample is a diamond shaped blue pill that has different dosages 25 mg, 50 mg and 100 mg. Generic Viagra samples, though, are often counterfeited: there are so called herbal Viagra samples and natural Viagra samples which resemble the original in shape and color.

Later there appeared other generic Viagra analogues which outperformed Viagra in several factors. First of all new samples have different from Viagra dosages. For instance, generic Viagra successor Vardenafil known under the trade name Levitra is available in 2.5 mg, 5 mg, 10 mg and 20 mg where 10 mg of Levitra sample is almost equal to 50 mg of Viagra sample. Next successor of Viagra and Levitra was Cialis (tadalafil). It had one incontestable advantage the period of half-life was almost four times as long as the period of Viagra and Levitra: 17.5 hours compared to 4-5 hours.

Generic Viagra and its other equivalents are PDF-5 inhibitors. These enzymes are responsible for the blood flow to the penis. But generic Viagra also inhibits the enzyme PDE-6. This enzyme results in the high sensitivity of photoreceptors in the eye. This may result in abnormal vision, eye pain. Though there are other Viagra side effects which are generally common for the trio Viagra Cialis Levitra: gastrointestinal problems, nausea, headache, facial flushing, hypertension, nasal congestion, back pain, eye pain, itch, etc.

Generic Viagra is very popular nowadays and is sold via Internet. Internet sites and pharmacies also offer the services of online counseling. So there is possibility to get generic Viagra prescription without paying visit to your local hospital.