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  5. Questions and Answers for Cialis (tadalafil)
  1. Postmarket Drug Safety Information for Patients and Providers

Questions and Answers for Cialis (tadalafil)

1.  What is Cialis used to treat?

Cialis is approved for the treatment of men who experience difficulty having and maintaining an erection (impotence).

2.  How does Cialis work?

Cialis works by enhancing the effects of one of the chemicals the body normally releases into the penis during sexual arousal. This allows an increase of blood flow into the penis. An erection is the result of an increase in blood flow into certain internal areas of the penis.

3.  How is Cialis different from the currently approved products for erectile dysfunction (ED)?

Cialis is different from other currently approved products for ED in that it stays in the body longer. However, there were no studies that directly compared the clinical efficacy and safety of Cialis to other products.

4.  How do I take Cialis?

Cialis is taken orally before sexual activity, not more than once daily. Cialis may be taken with or without food. In some patients, the dose strength and maximum frequency of use may be adjusted. For more detailed information consult with your health care provider.

5.  Are there any side effects with Cialis?

As with any drug product, there may be side effects. The most commonly reported side effects in patients treated with Cialis during the testing of the product were: 

  • headache
  • indigestion
  • back pain
  • muscle pain
  • flushing
  • stuffy nose 

Patients who get back pain and muscle aches usually get them 12 to 24 hours after taking Cialis and these usually go away by themselves within 48 hours. A small number of patients taking Cialis also reported abnormal vision.

6.  What important information should you know about Cialis?

  • CIALIS can cause your blood pressure to drop suddenly to an unsafe level if it is taken with any nitrate medication. You could get dizzy, faint or have a heart attack or stroke.
  • Tell your healthcare provider that you take Cialis. If you need emergency medical care for a heart problem, it will be important for your health care provider to know when you last took Cialis.
  • After taking a single tablet, some of the active ingredient of Cialis remains in your body for more than 2 days. The active ingredient can remain longer if you have problems with your kidneys or liver, or you are taking certain other medications.
  • Physicians should discuss with patients the potential for CIALIS to augment the blood-pressure-lowering effect of alpha-blockers and antihypertensive medications.

7.  What should I talk to my doctor about when considering if Cialis is right for me?

Because sexual activity can increase the work of the heart, your doctors should talk to you about your heart’s general condition and if Cialis is right for you. Patients who have a condition called "left ventricular outlet obstruction" from valvular problems or heart muscle enlargement may get side effects such as fainting or light-headedness. Because patients with recent heart attacks or stroke, heart pains (angina), heart failure, uncontrolled blood pressure or uncontrolled irregular heart beats, severe liver disease, and retinal eye problems were not studied with Cialis, Cialis is not recommended for these patients. There may be rare occurrences of priapism or painful, prolonged erections. This is a serious condition that requires immediate medical attention. Patients should seek prompt medical attention if their erection lasts longer than four hours.

8.  Who should not take Cialis?

Cialis should not be used by patients taking nitrates (such as nitroglycerin tablets or patches) because the combination of these with Cialis could significantly lower blood pressure and lead to fainting or even death in some men.

9.  Can Cialis be used with other treatments for impotence?

The safety and effectiveness of Cialis when used with other treatments for impotence has not been studied. Combined use could lead to additional lowering of blood pressure, possibly to unsafe levels. Therefore the use of such treatments in combination with Cialis is not recommended.

10. What if I am taking other drugs?

Always discuss with your health care practitioner ALL of the medications you are taking (prescription and over-the-counter) that way, you can receive the best advice for your own situation. Cialis is not recommended for people taking any form of nitroglycerin because the combination may lower blood pressure to an unsafe level.

11.  How will Cialis be supplied?

Cialis will be available as oral tablets in 5mg, 10mg and 20mg strengths.

12. Will Cialis be prescription or OTC (over-the-counter)?

Cialis will be available by prescription only.

13.  When will Cialis be available to pharmacies?

FDA has no control over when products are available in pharmacies after FDA approval for marketing. The decision of availability is completely up to the company marketing the product. For further information contact your pharmacist or Eli Lilly and Company directly.

14.  How can I report a serious side effect with Cialis to FDA?

FDA encourages anyone aware of a serious side effect, including consumers or patients, to make a MedWatch report.

You can report an adverse event either online, by regular mail or by fax, using the contact information at the bottom of this page.

 

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