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Fmedingenuityrequently Asked Questions on VIAGRA (Sildenafil)

Q: What is Viagra?

A: Viagra is a new medication that is taken by mouth to restore erectile function in men with erectile dysfunction. It is the first of its kind. It works selectively on the penis. It is not a hormone or an aphrodisiac.

Q: Is this drug safe?

A: YES it is. Viagra has been extensively tested in over 4500 men over the past three years. The incidence of adverse side effects causing patients to drop out of the studies was equal in patients taking placebo versus Viagra, 2.5%.

Q: How does the pill work?

A: Viagra works by increasing the smooth muscle relaxation in the penis. When an erection occurs, the smooth muscles in the penis and in the arteries of the penis must be relaxed. Viagra maximizes the relaxation increasing the efficiency of the erection. It is like stretching a rubber balloon before blowing it up to make it easier to inflate. The enzyme that the medication specifically works on is phosphodiesterase type 5 (PDE-5) which is almost exclusively found in the penis.

Q: Will the medication cause relaxation of all the smooth muscles in the body?

A: NO. The enzyme (PDE-5) is specific to the penis. Viagra is highly specific for the enzyme in the penis. The minimal cross-reaction is responsible for the side effects.

Q: What are the side effects?


  • Mild headache 16%
  • Flushing 11%
  • Indigestion 7%
  • Runny nose 7%
  • Transient visual disturbance (blue haze) 3%

Q: Will Viagra affect my visual acuity (blurry vision)?

A: NO. This has been extensively tested.

Q: Will Viagra affect my night vision while driving?

A: NO. This has been extensively tested.

Q: Are there any serious side effects.

A: NO. The incidence of serious cardiovascular side effects in over 4500 men studied was equal in the placebo and treatment group, less than 2%. There were no deaths in the studies.

Important note: Patients who take or need nitroglycerin or nitrates for heart disease cannot use this drug. A number of heart attacks, some causing death, have been reported since the introduction of Viagra. These appear to be due to the exertion of sexual intercourse or to the use of nitroglycerin with Viagra against doctor's orders. Patients with significant heart disease, whether using nitroglycerin or not, should be counselled about the risk of heart attack.

Q: Does this drug cause an erection that will not go down (priapism)?

A: NO. There were NO episodes of priapism in any of the studies. Viagra does not cause erections without sexual stimulation. It is not like penile injections or intraurethral therapy. Its mechanism of action is totally different.

Q: When I use the injections, sometimes my erection will last after I have an orgasm. Will that happen with Viagra?

A: NO. That is one of the remarkable attributes of the pill. It is natural. If there is no sexual stimulation the erection subsides naturally.

Q: Can I use this with my injections or MUSE if they are not working well.

A: NO. The use of Viagra with other forms of therapy (injections, MUSE, vacuum device) has not been tested and should be avoided.

Q: Are there any contraindications?

A: YES. The only contraindication is the use of nitrates (sublingual nitroglycerine, long-acting nitrates, nitrate pastes). Several patients have fainted while using nitrates and Viagra because of the drop in blood pressure. No patients have had any serious consequences after fainting. If you are unsure whether you are on these medications, check with your internist or cardiologist before considering this medication.

Q: What about any interactions with other medications?

A: There have been no interactions with other medications including diabetic medications, blood thinners, antacids, aspirin or alcohol. Cimetidine and erythromycin did result in increased blood levels but without any complications.

Q: Is there any minimum or maximum age?

A: It has been tested and found to be safe in men up to 85 years old. Viagra has not been tested in men younger than 18. It is not indicated in the pediatric age group.

Q: How do I take it?

A: It should be taken 1 to 2 hours prior to intercourse. The peak blood level occurs in less than 60 minutes.

Q: Will I get a spontaneous erection in 60 minutes?

A: NO. Again, the beauty of the pill is that it works with natural stimulation. No stimulation means no erection.

Q: What happens if I don't use it in an hour?

A: The beneficial effect can be seen as late as 8 hours. Most of the effectiveness is within the first 4 hours. You will not have an erection if you are not stimulated.

Q: How often can I use it?

A: The recommended usage is once a day.

Q: What dose should I use? Are there several doses?

A: Viagra comes in 25 mg, 50 mg and 100 mg pills. You should use the lowest dose that works. The higher the dose you use the higher the side effects. I recommend starting at a dose of 50 mg. You can always increase or decrease your dose according to your response. 100 mg is the maximum dose per day.

Q: Can I overdose on the drug?

A: The higher the dose used in the trials, the more problematic the side effects were. In some of the Canadian trials a dose of 200 mg was used without improved efficacy and with more side effects. Viagra has been administered in doses 8 times the recommended dose without significant safety concerns.

Q: Will the medication affect my orgasm?

A: NO. As the pill depends on stimulation to be effective, orgasms are not affected.

Q: Should I worry if I am trying to have a child?

A: There is no absolute answer to that question and caution should be advised. There have been several pregnancies during the trial that have not been problematic. This specific question has not been investigated in the trials. Viagra has not been found to have any affect on sperm motility and has not had any affect on fertility or increased birth defects in animals.

Q: Will it cause cancer?

A: NO. Extensive testing in animals revealed no evidence of cancer causing potential in animals.

Q: Will this pill increase my libido (sex drive) or my aggressiveness?

A: NO. Viagra has no affect on libido. Extensive psychologic testing has revealed no increase in aggressive behavior or desire.

Q: In what % of men is Viagra effective?

A: The effectiveness of the medication depends on the cause of the problem. If there is a serious lack of blood flow the medication will probably not work. Overall, looking at the studies, the pill was successful in 70% of patients. Diabetic men and men who have had radical prostate or bladder surgery have a lower success rate.

Q: What if it doesn't work?

A: Viagra requires sexual excitation to work. You may be too tired or insufficiently sexually excited. If it does not work repeatedly you should make an appointment to discuss treatment alternatives.

Q: Will this be reimbursed by my insurance company?

A: Many medication plans reimburse for the treatment of erectile dysfunction, however many do not. Check with your individual plan administrator.

Q: What is the cost of VIAGRA?

A: Each pharmacy is different and shopping may save you money. Pharmacies are charging between $7.50 and $11.00 per pill. The price of the pill is independent of the pill dosage. The pills are not scored and are not intended to be divided. If you are using two 50 mg tablets, you can reduce costs by 50% by using the 100 mg tablets.

Q: Can VIAGRA be used in women?

A: The FDA has not approved VIAGRA in women. Its safety and effectiveness has not been established in any group other than men over the age of 18.


Reprinted with permission from Dialog Medical, dialogmedical.com.








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