Sildenafil citrate is a chemical substance that was created by British scientists and then marketed by the pharmaceutical company Pfizer based in US. Sildenafil citrate is sold under very popular brands Viagra and Revatio and under various other trade names.
Sildenafil citrate is indicated for the treatment of erectile dysfunction in men and pulmonary arterial hypertension (PAH) in both men and women.
The medication works by restraining cyclic GMP – a specific phosphodiesterase type 5. PDE type 5 is an enzyme which postpones a degradation of cGMP, which is responsible for regulation of blood flow. Thus sildenafil relaxes muscles and increases blood flow to particular areas of the body.
Sildenafil under the name of Viagra is administered to treat erectile dysfunction in men. Revatio is the other brand used to treat pulmonary arterial hypertension and improve exercise capacity in men and women.
Sildenafil citrate is a prescription medication, so you should consult your doctor before using it. Inform your doctor if you have allergic reactions to Sildenafil or if you suffer from other chronic of serious conditions. You should tell your doctor about all other medications you are using. Sildenafil interacts with the following medications:
- tadalafil (Cialis), vardenafil (Levitra);
- bosentan (Tracleer);
- cimetidine (Tagamet);
- conivaptan (Vaprisol);
- imatinib (Gleevec);
- isoniazid (for treating tuberculosis);
- rifampin (Rifadin, Rimactane Rifater, Rifamate);
- an antidepressant such as nefazodone;
- an antibiotic such as clarithromycin (Biaxin), dalfopristin/quinupristin (Synercid), erythromycin (E.E.S., EryPed, Ery-Tab, Erythrocin, Pediazole), or telithromycin (Ketek);
- antifungal medication such as itraconazole (Sporanox), ketoconazole (Nizoral), miconazole (Oravig), or voriconazole (Vfend);
- heart or blood pressure medication such as diltiazem (Cardizem, Dilacor, Tiazac), doxazosin (Cardura), nicardipine (Cardene), quinidine (Quin-G), verapamil (Calan, Covera, Isoptin, Verelan);
- HIV/AIDS medicine such as atazanavir (Reyataz), delavirdine (Rescriptor), fosamprenavir (Lexiva), indinavir (Crixivan), nelfinavir (Viracept), saquinavir (Invirase), or ritonavir (Norvir, Kaletra).
Sildenafil citrate should not be co-administered with nitrates, alpha blockers and any medications which have pressure lowering effects.
Sildenafil is to be taken as your doctor directs you to do. Never exceed the recommended dose of your medication, to avoid dangerous health conditions which overdosing may provoke.
Revatio for PAN is used in the dose of 20 mg orally, three times a day, with periods between the doses of 4 to 6 hours. The medication may be administered in a form of injection 3 times a day.
Viagra for ED is use only when needed, 30 minutes to 4 hours before sexual activity. The medication will not provide an automatic erection; a person should be sexually aroused. The recommended starting dose is 50 mg. The dose depends on different factors: general health of a patient, age, other disorders a patients has; his clinical response and tolerability. The dose may be changed to have the beneficial result from the treatment or to avoid complications.
Sildenafil may cause adverse reactions from different systems of the body. Some of these reactions are dangerous for health and require medical help. You should seek emergency medical attention if you experience the following conditions:
- Severe allergic reactions;
- Pain, numbness, or tingling in the chest, arms, neck, or jaw;
- Sudden vision loss;
- Ringing in the ears, or sudden hearing loss;
- Irregular heartbeat;
- Shortness of breath;
- Prolonged and painful penile erection (priapism).
In all other cases, if you have warmth or redness in the face, stuffy nose, headache, upset stomach you need to report these side effects to your general practitioner.
To avoid dangerous side effects of Sildenafil you should not take it together with grapefruit products, alcohol and other medicines to treat ED, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin).