A B O U T    Y O U R    M E D I C I N E

Available as tablets containing Sildenafil 25 mg, 50 mg and 100 mg supplied under the trade name ViagraÒ .

Sildenafil increases the flow of blood into the erectile tissue of the penis so increasing the likelihood of erection sufficient to permit sexual intercourse. It is used for the treatment of male erectile dysfunction (impotence) and in a number of endocrine/metabolic situations:

hypopituitarism in which there is failure of the pituitary gland to stimulate production of testosterone (the male sex hormone).

hypogonadism in which there is underproduction of testosterone by the testes (testicles). In practice, treatment with Sildenafil appears to be effective on up to 75% of occasions (i.e. three times out of four).

Diabetes mellitus where effectiveness is nearer 50%

Note that Sildenafil is not an aphrodisiac and has no effect on sexual desire. It is not therefore very effective in the absence of normal sexual stimulation.

How do I take it?

• The usual dose of Sildenafil which is required to achieve an erection is 50 mg taken about 30 minutes to 1 hour before sexual intercourse is intended. It acts more rapidly if taken on an empty stomach since the presence of food can delay its absorption.
• Older patients or others who are very sensitive to the action of Sildenafil (including people with kidney or liver disease) will often require to take only one 25 mg tablet. On the other hand, a dose of 75 mg and up to 100 mg (the absolute maximum single dose) may be necessary for some people.
• No more than one dose of Sildenafil should be taken each day and, indeed, many Doctors will follow the advice to limit their prescribing to around one dose per week in most cases.

What side effects can be expected?

• The most common side effects of Sildenafil are headache, flushing and dizziness which may affect 10% or more of those who take it. This is not undexpected since the medicine affects blood flow throughout the body and this is the reason why people with heart conditions of those who have had a stroke must undergo a medical check up before treatment is prescribed. People who take medication for angina and heart failure (including Glyceryl Trinitrate Spray or Tablets in the mouth for chest pain) should not use Sildenafil. Note also that the exertion of sexual intercourse itself may cause significant problems (breathlessness, chest pain, fainting) in such cases.
• Sildenafil causes indigestion in about 5-10% of people and visual disturbances (blurring of vision, colour tinge, increased brightness) and nasal congestion in a similar number.
• It has been reported on occasion to produce a prolonged and even painful erection (a condition known as priapism). If erections have not subsided after an hour or so of intercourse, your Doctor should be consulted.

Treatment with some well known medicines (Erythromycin, Cimetidine, Itraconazole, Ketoconazole) can theoretically prolong the action of Sildenafil and increase the likelihood of side effects. In practice, however, this has not (so far) been shown to be important but concurrent treatment with Saquinivir or Ritonavir, and possibly related medicines used in the treatment of AIDS, has been shown to have a more substantial effect on the action of Sildenafil. If in doubt – seek advice from your Doctor.

Sildenafil tablets should be stored in the blister packs at room temperature. Avoid exposure to excessive heat or moisture. Tablets stored in this way may be used for up to 3 years after their manufacture.

Top

Ó NHS Tayside; 2006; version 1.0

Disclaimer; no liability whatsoever is accepted for information given and all such information, especially with regard to drug usage (UK version provided), must be checked with a person’s health provider.