Cialis Contraindications

The American pharmaceutical company Lilly manufactures the drug tadalafil under the brand name Cialis. Lilly began testing Cialis in the late 1990s in conjunction with the biotech firm ICOS, which first manufactured tadalafil in 1993. After tadalafil received approval from the Federal Food and Drug Administration, Lilly began selling Cialis as a treatment for erectile dysfunction in 2004.

Medical History

• Cialis is not recommended for patients suffering from a number of acquired medical conditions or undergoing certain types of medical treatment. This medication opens up blood flow in the veins and exerts a direct, lowering effect on blood pressure. The Drugs website advises patients against using Cialis if they have experienced congestive heart failure or stroke in the past six months. Patients who have suffered a mild heart attack in the past 90 days should also avoid taking Cialis. Individuals with arrhythmia, high blood pressure or those who feel chest pain, or angina, on a regular basis or during sexual intercourse should consult a physician before taking Cialis.

  Drugs website also reports contraindications for patients with liver and kidney disease, as these organs may not be able to process Cialis. RxList reports that patients currently undergoing hemodialysis can take Cialis but only at the minimum dosage of 5 mg, once daily.

Pre-Existing Conditions

• Patients with certain genetic conditions should also avoid taking Cialis. RxList lists "retinitis pigmentosa" and sickle cell anemia as contraindicating Cialis treatment. Also, patients allergic to Cialis should avoid taking this drug, as it can cause hives, rashes and itching, as well as more dangerous allergic reactions such as labored breathing and swelling of the mouth or tongue that can obstruct breathing.

  Patients with a history of priapism, which is a frequent occurrence of a prolonged erection, should also avoid taking Cialis. The Drugs website also contraindicates Cialis use for individuals with Peyronie's disease, which produces potentially painful scar tissue inside the penis, or individuals with an otherwise deformed penis that might experience pain during a persistent erection.

Drug Interactions

• The Drugs website reports that patients already taking certain medications should not take Cialis because of the way that Cialis interacts with or amplifies the effect of these drugs. RxList suggests that patients taking the class of high blood pressure medications known as alpha-blockers can also take Cialis at the lowest recommended dosage, although Drugs reports that taking these two medications together can lead to low blood pressure. Low blood pressure can cause patients to faint, become dizzy or experience lightheadedness.

  Drugs specifically lists amyl nitrite and any brand name versions of nitroglycerin and isosorbide dinitrate as among the prescriptions that can cause this effect. According to Drugs, the restrictions on amyl nitrite and similar drugs applies even for patients who take them recreationally as a psychotropic. RxList recommends that patients who have taken Cialis should wait at least 48 hours before taking nitrates to reduce chest pain. RxList states that high intake of alcohol (more than five drinks) combined with Cialis can also lead to dangerously low blood pressure.

  Drugs also indicates that certain classes of medications can amplify possible side effects of Cialis. These drugs include the Azole class of anti-fungal medication used to treat fungal infections, the class of HIV medications called protease inhibitors and the antibiotics erythromycin and telithromycin.