Viagra Product Summary
The following information is a summary about Viagra®
. It is not intended to replace a doctor's instructions.
(Sildenafil - ORAL)
USES
This medication is used to treat male sexual function problems (erection
problems).
HOW TO USE THIS MEDICATION
This drug is taken by mouth as needed between four hours and one-half hour
before sexual activity (about one hour before is most effective). Take only as
directed, usually once daily as needed. Sildenafil works along with sexual
stimulation to help achieve an erection.
SIDE EFFECTS
Headache, flushing, stomach upset, nasal stuffiness, diarrhea and dizziness
might occur. If these effects persist or worsen, notify your doctor promptly.
PRECAUTIONS
Before using this drug, tell your doctor your medical history, including any
allergies (especially drug allergies), any penis conditions such as
fibrosis/scarring, history of painful/prolonged erection (priapism), sickle cell
anemia, blood system cancers (such as leukemia or myeloma), or Peyronie's
disease, eye problems (retina diseases). kidney or liver disease, bleeding
disorders or active stomach ulcers, heart diseases, stroke or severe high or low
blood pressure. Limit alcohol intake, as it may aggravate side effects of this
drug. To avoid dizziness and lightheadedness when rising from a seated or lying
position, get up slowly. The elderly may be more sensitive to the side effects
of this drug, therefore caution is advised in this group.
DRUG INTERACTIONS
Tell your doctor of all nonprescription and prescription medication you may use,
especially any nitrate medications (e.g., nitroglycerin, isosorbide dinitrate),
nitroprusside (any "nitric oxide donor" medicines), cimetidine,
erythromycin, azole antifungals (e.g., itraconazole, ketoconazole), mibefradil,
rifamycins (e.g., rifampin) or high blood pressure medicines.
NOTES
Do not share this medication with others, since they may have a problem that is
not effectively treated by this drug. Use of Viagra does not protect against
sexually transmitted diseases (e.g., HIV, Hepatitis B, gonorrhea).
MISSED DOSE
Not applicable.
STORAGE
Store at room temperature between 59 and 86 degrees F (15-30 degrees C) away
from light and moisture. Keep this and all medications out of the reach of
children.
First Oral Therapy for Erectile Dysfunction
FDA has approved sildenafil, the first oral tablet to treat erectile dysfunction
(ED). Taken about an hour before anticipated sexual activity, sildenafil
enhances the response to sexual stimulation. It led to at least some improvement
in 7 out of 10 men with ED compared with 2 out of 10 who improved on placebo.
In clinical studies, sildenafil was assessed for its effect on the ability of
men with ED to engage in sexual activity and in many cases specifically on their
ability to achieve and maintain an erection sufficient for satisfactory sexual
activity. It was evaluated primarily at doses of 25 mg, 50 mg, and 100 mg in 21
randomized, double-blind, placebo-controlled trials of up to 6 months in
duration. Sildenafil was administered to more than 3,000 patients aged 19 to 87
years, with ED of various etiologies (organic, psychogenic, mixed) with a mean
duration of 5 years. The drug demonstrated statistically significant improvement
compared with placebo in all 21 studies.
The first in a new class of medications, sildenafil is a selective inhibitor
of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5
(PDE5). Physiologically, sexual stimulation causes local release of nitric oxide
(NO) in the corpus caver-nosum. NO then activates the enzyme guanylate cyclase,
which results in increased levels of cGMP, producing smooth muscle relaxation in
the corpus cavernosum and allowing inflow of blood. Sildenafil enhances the
effect of NO by inhibiting PDE5, which is responsible for degradation of cGMP in
the corpus cavernosum.
Sildenafil was effective in a broad range of ED patients, including those
whose ED arose from diabetes mellitus, spinal cord injury, transurethral
resection of the prostate, or no known physical cause. It was used in patients
with a history of coronary artery disease, hypertension, peripheral vascular
disease, depression, or coronary artery bypass graft, and in patients taking
various drugs, including antidepressants/antipsychotics and antihypertensives/diuretics.
For most patients, the recommended dose is 50 mg, taken as needed
approximately 1 hour before sexual activity. However, the drug may be taken
anywhere from one-half hour to 4 hours before sexual activity. Based on
effectiveness and toleration, the dose may be increased to a maximum recommended
dose of 100 mg or decreased to 25 mg. The maximum recommended dosing frequency
is once a day. Sildenafil was shown to potentiate the hypotensive effects of
nitrates, and its administration in patients who use various nitrates in any
form is therefore contraindicated.
Sildenafil's side effects, when they occur, are usually mild and temporary.
The most common side effects reported in clinical trials included headache,
flushing, and upset stomach. Visual changes, such as mild and temporary changes
in blue/green color perception or increased sensitivity to light, can occur.
A thorough medical history and physical examination should be undertaken to
diagnose ED, determine potential underlying causes, and identify appropriate
treatment.There is a degree of cardiac risk associated with sexual activity;
therefore, physicians may wish to consider the cardiovascular status of their
patients prior to initiating any treatment for ED.
Sildenafil is manufactured by Pfizer Pharmaceuticals, New York, NY, and
marketed under the trade name Viagra. The company reported to FDA on May 21,
1998, that it learned of the deaths of six people who had taken sildenafil. FDA
is investigating these reports and will continue to monitor any other serious
adverse event reports to determine if any changes exist in this drug's safety
profile. The label states that Viagra and the concomitant administration
of nitroglycerin or other organic nitrates is contraindicated.
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Dysfunction page
Possible uses of this medication
Viagra is used to treat male sexual function problems (erection problems).
How to take this medication
Viagra is taken by mouth as needed between four hours and one-half hour before
sexual activity (about one hour before is most effective). Take only as
directed, usually once daily as needed. Sildenafil works along with sexual
stimulation to help achieve an erection.
Side Effects
Headache, flushing, stomach upset, nasal stuffiness, diarrhea and dizziness
might occur. If these effects persist or worsen, notify your doctor promptly.
Precautions
Before using Viagra, tell your doctor your medical history, including any
allergies (especially drug allergies), any penis conditions such as
fibrosis/scarring, history of painful/prolonged erection (priapism), sickle cell
anemia, blood system cancers (such as leukemia or myeloma), or Peyronie's
disease, eye problems (retina diseases). kidney or liver disease, bleeding
disorders or active stomach ulcers, heart diseases, stroke or severe high or low
blood pressure. Limit alcohol intake, as it may aggravate side effects of this
drug. To avoid dizziness and lightheadedness when rising from a seated or lying
position, get up slowly. The elderly may be more sensitive to the side effects
of this drug, therefore caution is advised in this group.
Drug Interactions
Tell your doctor of all nonprescription and prescription medication you may use,
especially any nitrate medications (e.g., nitroglycerin, isosorbide dinitrate),
nitroprusside (any "nitric oxide donor" medicines), cimetidine,
erythromycin, azole antifungals (e.g., itraconazole, ketoconazole), mibefradil,
rifamycins (e.g., rifampin) or high blood pressure medicines.
Missed Dose
Not applicable.
Storage
Store at room temperature between 59 and 86 degrees F (15-30 degrees C) away
from light and moisture. Keep this and all medications out of the reach of
children.
Notes
Do not share Viagra with others, since they may have a problem that is not
effectively treated by this drug. Use of this drug does not protect against
sexually transmitted diseases (e.g., HIV, Hepatitis B, gonorrhea).
Click here to return to the Erectile
Dysfunction page
