Drug Name: Viagra/Sildenafil

Drug Uses:
Viagra is useful to treat male impotence or erectile dysfunction. The drug improves the blood flow into the penis so that an erection is maintained during sexual intercourse.

Dosage:
Viagra is to be taken at least 30 minutes or an hour prior to sexual activity. It can also be taken up until four hours ahead of the sexual activity. Viagra is to be taken only once per day.

Drug Class and Formula:
Viagra is classified as a phosphodiesterase type 5 inhibitor that functions by increasing the flow of blood into the penis to attain an erection and maintain it during the sexual act.

Missed Dosage:
Since Viagra is to be used as per requirement, there is no fixed schedule for taking the drug.

Storage:
Viagra must be stored in its original container at room temperature which can be 59-86° F or 15-30° C. It must be protected from heat, light and moisture and kept away from the reach of children.

Precautions and Warnings

Viagra should not be taken by people who have been prescribed nitrate drugs for heart problems. These would include prescriptions of nitroglycerin like Nitrostat, Nitrolingual, Nitro-Dur, Minitran, Nitro-Bid, Deponit and Transderm-Nitro. It also includes isosorbide dinitrates like Isordil, Dilatrate-SR and Sorbitrate and isosorbide mononitrates like ISMO, Imdur and Monoket. If you are taking recreational drugs like amyl nitrate or nitrites (poppers), then you must not take Viagra.

Let your doctor know if you are on any other medication for erectile dysfunction or if you use any of the below-mentioned medicine:

• bosentan (Tracleer);
• a blood thinner like warfarin (Coumadin);
• cimetidine (Tagamet, Tagamet HB);
• antibiotics such as erythromycin (E-Mycin, Ery-Tab, Eryc,) or clarithromycin (Biaxin);
• doxazosin (Cardura), prazosin (Minipress), Terazosin (Hytrin);
• HIV medications like amprenavir (Agenerase), darunavir (Prezista), tipranavir (Aptivus), efavirenz (Sustiva), indinavir (Crixivan), nevirapine (Viramune), saquinavir (Invirase, Fortovase), fosamprenavir (Lexiva), lopinavir/ritonavir (Kaletra), atazanavir (Reyataz), ritonavir (Norvir) or nelfinavir (Viracept);
• any antifungal medication like itraconazole (Sporanox) or ketoconazole (Nizoral);
• phenobarbital (Luminal), carbamazepine (Tegretol) or phenytoin (Dilantin);
• rifabutin (Mycobutin) or rifampin (Rifadin, Rimactane).

Whenever you start a new medication, it is advisable to let your doctor know if you are taking any other medication or over-the-counter drugs. If you are taking herbal products, vitamins or minerals, let your doctor know about it. Also, avoid starting a new medicine without informing your doctor.

If you have severe heart problems that make sexual activity dangerous, then you should not use Viagra. You must be extremely cautious to use Viagra if you have acute heart irregularities or have suffered from a stroke or heart attack in the past six months. You must also be extremely vigilant if you suffer from high or low blood pressure or chest pain.

During sexual activity, if you develop nausea, dizziness, chest pain or any other cardiac symptoms, you must stop immediately and consult your doctor about these issues as soon as possible.

In case the erection lasts for more than four hours, it could lead to a permanent damage resulting in impotence. Hence, in such cases, immediate treatment is called for. Persons having a condition like multiple myeloma (bone marrow disease), leukemia or sickle cell anemia must use Viagra with care. The drug should be used cautiously by persons with a genital problem or Peyronie's disease.

Viagra must be used with caution if you have stomach ulcers, bleeding disorders or the hereditary eye condition known as retinitis pigmentosa, since no studies have been conducted about the safe use of the drug in these cases.

Possible Side Effects

You must obtain immediate medical attention and inform your doctor if you experience any of the below-mentioned symptoms upon using Viagra:

• Sudden loss of vision
• Ringing in the ears, or sudden loss of hearing
• Chest pain or a feeling of heaviness, pain spreading to the arm or shoulder, sweating, nausea or general ill feeling
• An irregular heartbeat
• A swelling in the hands, the ankles or feet
• A shortness of breath
• Any changes in vision
• A feeling of light-headedness, fainting
• A painful penis erection or one that lasts more than 4 hours.

Some other but less serious ill effects may include:

• Stuffy nose
• Headache
• Warmth or redness on the face, the neck or chest
• An upset stomach
• Back pain.

Since the above is not a complete list of the ill effects, there may be other symptoms which you may encounter upon using Viagra. Make sure to inform your doctor about any abnormal or worrisome symptoms you may come across.

Other Information:

If you are over 65, and using Viagra, you may suffer from side effects. Your doctor may, however, recommend a lower dosage of this drug.