Classification:
Viagra (sildenafil) belongs to a group of medicines that delay the enzymes called phosphodiesterase from working too quickly. By delaying the action of phosphodiesterase, blood remains in the penis longer, maintaining an erection for a longer period of time.
Form:
- 25mg tablets
- 50mg tablets
- 100mg tablets
Usual Dosage:
- For adults up to 65 years of age, Viagra 50mg is prescribed to be taken once a day, 30 minutes to 4 hours before intercourse. In situations where 50mg isn't effective, your doctor can prescribe 100mg to be taken once daily 30 minutes to 4 hours before intercourse.
- For men older than 65 years of age, Viagra 25mg is prescribed to be taken 30 minutes to 4 hours before intercourse. In some circumstances, men older then 65 may have their doses increased.
Instructions:
- Can be taken with or without food.
- Take 30 minutes to 4 hours before intercourse.
- Always start with the lowest effective dose.
Viagra Side Effects to Report to Your Doctor:
Special Warning! - If you experience any sudden change in vision or loss of vision stop taking Viagra and contact your doctor immediately.
Common
- flushing
- headache
- nasal congestion
- stomach discomfort following meals
- blurred vision, seeing shades of colors differently than before, or sensitivity to light
- bladder pain
- cloudy or bloody urine
- dizziness
- increased frequency of urination
- pain on urination
- diarrhea
If you experience an erection that lasts more than 4 hours seek medical attention.
Drug Interactions and Incompatibility:
- Protease Inhibitors (Reyataz, Crixivan, Invirase, Norvir, Viracept,Fortovase, Agenerase, Lopinavir) increase the amount of Viagra in your blood and prolongs the action of Viagra. Men on Protease Inhibitors should start with a dose of 25mg with a maximum of 50mg.
- Nitrates, such as nitroglycerin (e.g., Nitrostat or Transderm-Nitro) - Sildenafil further lowers the blood pressure along with nitrates which may result in an abnormally low blood pressure. Use of Viagra with nitrates should be avoided.
For More information:
For more information on Viagra try About.com's Drug Finder.
