Viagra vs. Cialis vs. Levitra: Differences and Similarities

Ready to combat ED (erectile dysfunction) but confused about which type of PDE-5 inhibitor to take? You’re not the only one. Of the 3 FDA approved PDE-5 inhibitors, Viagra (sildenafil citrate) is definitely the most popular, but popularity alone shouldn’t be a determining factor. The more recently approved Cialis (tadalafil) and Levitra (vardenafil hydrochloride) are also highly effective and very safe alternatives, although they may not be as popular yet. The problem for most people is actually deciding on the best alternative for them.
For starters, all three drugs are PDE-5 inhibitors so they help relax compromised or hardened penile arteries thus allowing more blood to flow into the penis and subsequently cause an erection. All three drugs also help keep high levels of cGMP within the penis. What’s cGMP? It means cyclic guanosine monophosphate and it is an incredible substance which is naturally produced by the penile tissue in response to sexual stimulation and which aids vascular muscle relaxation. When high levels of cGMP are present, the penile arteries become relaxed and a natural and stiff erection will occur.
Unfortunately, in most men suffering from E.D., the PDE-5 enzyme neutralizes any available cGMP and without cGMP an erection will become flaccid or will not occur at all. That’s where PDE-5 inhibitors such as Viagra, Cialis and Levitra come in. These drugs “inhibit” or block the unwanted PDE-5 and hence the very much wanted cGMP is allowed to remain within the penis after sexual stimulation occurs, thus aiding the erection process and keeping the penis erect. The question is, “Since all of these drugs have the same effect, why should I choose one over another?”
Let’s compare the three PDE-5 inhibitors side by side to determine their differences:
Manufacturers:
Viagra: Pfizer

Cialis: Eli Lilly and ICOS

Levitra: GlaxoSmithKline and Bayer
Generic Name:
Viagra: Sildenafil Citrate

Cialis: tadalafil

Levitra: vardenafil hydrochloride

Dosages: Available and Recommended:
Viagra: 25 mg, 50 mg, and 100 mg tablets. Most patients begin using the 50 mg pill and either increase or decrease the dosage based on drug tolerance and / or effectiveness. Most healthcare practitioners recommend taking Viagra 1 hour prior to sexual activity but studies have shown that Viagra can actually be taken anywhere from 30 minutes to 4 hours before having sex.
Cialis: 5 mg, 10 mg, and 20 mg tablets. It is recommended that you start out using 10 mg tablets and either increase or decrease the dosage depending on the results achieved. Traditionally, Cialis tablets can be taken anywhere from 30 minutes to 12 hours prior to sexual activity. Cialis soft tabs (which need not go through the digestion process) may be taken around 15 minutes prior to sexual activity.
Levitra: 2.5-mg, 5-mg, 10-mg, and 20-mg. Most people start out on the 10 mg pill and either work their way up or down depending on the results achieved. Levitra should be taken anywhere from 25 minutes to 1 hour prior to sexual activity, though some experts claim sex can be initiated in as early as 15 minutes.
How long does the effect last?
Viagra: approximately 4 hours

Cialis: approximately 17 to 36 hours (This is why they call Cialis the weekend pill.)

Levitra: approximately 5 hours
Year approved by the FDA:
Viagra: March 27, 1998

Cialis: November 1, 2003

Levitra: August 20, 2003
Cost of Pill
The cost for each of the 3 drugs is similar though Cialis tends to be a bit cheaper.

Success Rate
All three drugs work for approximately 70 percent of all men. Unfortunately, PDE-5 inhibitors won’t work for everyone. Certain men may need to use alternative treatments such as vacuum pump devices or even penile implants.
Side Effects
All three drugs share most of the same side effects. Some men may experience headaches, flushing, back pain, runny noses, stomach aches, or even changes in vision (example: some Viagra studies have revealed that on rare occasions a man may begin seeing a bluish tinge but that should go away after the drug has been eliminated from the body). These are all common side effects and should not be reason to worry excessively.
None of the three PDE-5 inhibitors should be taken in combination with low blood pressure medication as this can potentially cause a person to have a heart attack. People with high blood pressure should also take PDE-5 inhibitors only after consulting with their doctor. In fact you should never self-prescribe yourself with any of the 3 PDE-5 inhibitors or any other prescription drug for that matter. Even if you are purchasing your PDE-5 inhibitors online you must still open up and tell the pharmacist everything he/she needs to know in order to properly formulate the correct treatment for you.
What the drug looks like:
Viagra: Small blue tablet with the word Pfizer engraved in the middle.

Cialis: Yellow tablet that is almond shaped and film coated.

Levitra: Orange tablet with a flame logo.
Notable Differences
Basically the only major difference between the three drugs is that Levitra begins working the fastest and will work regardless of what kind of food you have previously eaten. Viagra has the proven track record and has been trusted by over 30 million men and Cialis is the longest lasting. In the end though, the real choice is up to you.

John Scott, the author of this article, is a medical journalist collaborating with "Man of People" site.

Related Tags: Viagra, cialis.