Viagra is a prescription drug that relaxes the muscles found in the walls of blood vessels and increases blood flow to some regions of the body. It is approved to treat erectile dysfunction (ED). 

ED is a condition that makes it impossible or difficult to have and maintain an erection, and Viagra is effective in correcting that, but only for males 18 years and older.  

Viagra belongs to a group of drugs called phosphodiesterase type 5 (PDE5) inhibitors. It contains sildenafil and works by increasing blood flow to the penis, which helps to keep it erect, but the drug only work if you are aroused. 

Dosage

This drug comes as a tablet that should be taken orally, and it is available in three strengths: 25mg, 50mg and 100mg. The dosage that is right for you will be described by your doctor according to the severity of your condition, age and past medical history. 

Viagra should be taken 30 minutes to 1 hour or at most 4 hours before sexual activity; do not take it more than once daily. Follow your doctor’s prescription or the directions on the prescription label for the correct dosage, but do not take it in smaller or larger amounts or for longer than recommended. 

If you have erectile dysfunction, viagra can help you have and maintain an erection when sexual stimulation occurs. Still, you can’t get an erection just by taking the drug. 

Side Effects of Viagra

During sexual activity, if you experience dizziness, nausea, numbness, pain, or tingling in your chest, neck, arms, and jaw, you have to stop and call your doctor right away. 

Other side effects of Viagra include:

• Headache.
• Indigestion.
• Flushing.
• Back pain.
• Stomach upset.
• Nasal congestion.
• Nausea.
• Muscle pain.
• Rash.
• Dizziness.
• Chest, jaw, or left arm pain.
• Mild and temporary vision changes, such as blurred vision, blue tinge in your vision and sensitivity to light.
• Cardiovascular problems include irregular heartbeat, heart attack, or stroke in people with heart disease.
• Painful erection and lasts more than four hours.
• Low blood pressure.

Precautions

Before using Viagra, tell your doctor if you are allergic to sildenafil or have any other allergies. Also, tell your doctor if you have a medical history of heart problems, stroke, liver disease, kidney disease, dehydration, eye problem, high or low blood pressure and penis conditions.

Do not take Viagra if you do not have any problems with erection or if a healthcare provider has not prescribed it.