Viagra (sildenafil) and Cialis (tadalafil) are both oral medications for treating erectile dysfunction. They both work in much the same way, by inhibiting an enzyme called phosphodiesterase type 5 (PDE5). During sexual arousal, nitric oxide is then released. This opens blood vessels in the penis, causing an erection.
Viagra is 84% effective, slightly better than Cialis at 81%. Both take effect roughly in about the same amount of time. Cialis begins to work in about 16 to 45 minutes, and Viagra goes to work after about 30 minutes. Cialis lasts longer in the system, making it better for men who need it for more than one day. Viagra is used “on demand” by men who need it for a shorter time right before sexual encounter. Viagra generally works for 4 to 5 hours, versus 36 hours for Cialis.
When Cialis is needed for one encounter, the usual dose is 10mg, or 20mg in the presence of benign prostatic hypertrophy (enlarged prostate). When the drug is taken on a daily basis, the usual dose is 2.5mg. Viagra is taken at a dose of 50mg, between a half hour and 4 hours before it will be needed; generally 1 hour seems to be the best time frame.
What are the side effects of Cialis and Viagra?
The most common side effects of PDE5 inhibitors are indigestion, headache, and flushing. They should only be taken with caution by patients with heart disease, high blood pressure, or a history of stroke within the previous six months. Particularly patients who are on nitrites (e.g. nitroglycerin) for their heart disease should not take PDE5 inhibitors.
How much do Cialis and Viagra cost?
The cost of Viagra ranges roughly from $13.00 to $500.00 for a bottle of 30 tablets, strength 20.0mg depending on pharmacy and strength. The price of Cialis ranges from $16.00 to $552.00 for a bottle of 30 tablets, strength 10.0mg.