Cialis is a prescription medicine taken by mouth for the treatment of erectile dysfunction (ED) in men. ED is a condition where the penis does not harden and expand when a man is sexually excited, or when he cannot keep an erection. Cialis may help a man with ED get and keep an erection when he is sexually excited. Cialis must be used only under a doctor’s care.
Cialis does not:

cure ED

increase a man’s sexual desire

protect a man or his partner from sexually transmitted diseases, including HIV. Speak to your healthcare professional about ways to guard against sexually transmitted diseases.

serve as a male form of birth control

Cialis is only for men with ED. Cialis is not for women or children. Cialis must be used only under a healthcare professional’s care.

Who Should Not Take Cialis?

Do not take Cialis if you:

take any medicines called “nitrates”

use recreational drugs called “poppers” like amyl nitrate and butyl nitrate

have been told by your healthcare professional to not have sexual activity because of health problems

What are The Risks?

The following are the major possible risks and side effects of Cialis therapy. This list is not complete.

Cialis can cause your blood pressure to drop suddenly to an unsafe level if it is taken with certain other medicines such as nitrates and alpha-blockers, and recreational drugs that contain nitrates called “poppers.” A sudden drop in your blood pressure could cause you to become dizzy, faint, or have a heart attack or stroke.

Tell all your healthcare professionals that you take Cialis. If you need emergency medical care for a heart problem, it will be important for your healthcare professionals to know when you last took Cialis.

Cialis may uncommonly cause:

an erection that won’t go away (priapism)

vision changes, such as seeing a blue tinge to objects or having difficulty telling the difference between the colors blue and green

Some common side effects with Cialis include:

headache

indigestion

back pain

muscle aches

flushing

stuffy or runny nose

What Should I Tell My Healthcare Professional?

Tell your healthcare professional if you:

have or had heart problems

have low blood pressure or have high blood pressure that is not controlled

have had a stroke

have liver problems

have kidney problems or require dialysis

have ever had severe vision loss

have retinitis pigmentosa, a rare genetic (runs in families) eye disease

have stomach ulcers

have a bleeding problem

have a deformed penis shape or Peyronie’s disease

have had an erection that lasted more than 4 hours

have blood cell problems such as sickle cell anemia, multiple myeloma, or leukemia

take medicines called “alpha blockers” (alpha blockers are sometimes prescribed for prostate problems or high blood pressure)

Can Other Medicines or Food Affect Cialis?

Cialis and certain other medicines can interact with each other. Tell your healthcare professional about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Know the medicines you take. Keep a list of them with you to show your healthcare professional.