Cialis is the commercial name of the drug, Tadalafil. Tadalafil is an orally administered drug developed by the biotechnology company ICOS, for treating impotence brought by erectile dysfunction This drug, considered as the “third” impotence prescription drug after Sildenafil (Viagra) and Vardenafil (Levitra) by the Food and Drug Administration, is commonly sold in 5 mg, 10 mg, and 20 mg doses, and is yellow in color, film-coated, and almond-shaped.
Tadalafil is known as “The Weekend Pill” because it has a 36-hour effectiveness. Unlike Viagra and Levitra, it is prescribed as a “once daily” medication. It has been estimated that the number of men using Tadalafil worldwide has already reached 8 million.
Like any other drug, Tadalafil also brings side effects. Some of these symptoms are headaches, indigestion, back pain, muscle aches, flushing, and stuffy or runny nose. Back pain and muscle aches occur from 12 to 24 hours after taking the drug and usually disappears after 48 hours.
Like any other impotence-treating drugs, Tadalafil works through phosphodiesterase type 5 or PDE5. PD25 negatively interacts with other drugs, and thus patients prescribed with Tadalafil are required to avoid taking dosages of drugs that trigger such “interactions.” For example, PDE5 may cause hypotension, thus organic nitrates (which could only worsen hypotension) should not be taken for at least 48 hours after taking the last dose of Tadalafil.
Besides impotence, Tadalafil is also currently in “Phase 3” clinical trials for treating pulmonary arterial hypertension, an illness that leads to shortness of breath, dizziness, and fainting.