Viagra (sildenafil) tips from pharmacists

• You can take Viagra 30 minutes to 4 hours before sex. However, it works best if you take it roughly 60 minutes before sex.

• Viagra works faster if you take it on an empty stomach.

• You should not take Viagra if you are using nitroglycerin for chest pain. The combination of these two drugs can cause dangerously low blood pressure. 

• You should not use Viagra more than once a day at any dose.

• If you have an erection that lasts more than 4 hours, call your doctor or go to the emergency room. It could be a condition called priapism which can permanently damage the penis.

• Viagra does not protect against STDs (sexually transmitted diseases) such as herpes, chlamydia, gonorrhea, syphilis, and HIV.