tadalafil, Cialis (cont.)

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Tadalafil exaggerates the increases in heart rate and lowering of blood pressure caused by nitrates, for example, nitroglycerin, isosorbide dinitrate (Isordil), isosorbide mononitrate (Imdur, Ismo, Monoket), nitroglycerin (Nitro-Dur, Transderm-Nitro) that are used primarily for treating heart pain (angina). In patients who take nitrates for angina, tadalafil could cause heart pain or possibly even a heart attack by exaggerating the increase in heart rate and the lowering of blood pressure. Therefore, tadalafil should not be used with nitrates.

Tadalafil also exaggerates the blood pressure lowering effects of some alpha-blocking drugs for example, terazosin (Hytrin) that primarily are used for treating high blood pressure or enlargement of the prostate (BPH). Individuals who take these alpha-blockers should be on a stable dose of the alpha-blocker before tadalafil is started. In such situations, tadalafil should be started at the lowest dose. If the patient is already taking tadalafil, the alpha-blocker should be started at the lowest dose. Combining tadalafil with alpha-blockers for treatment of BPH is not recommended.

Tadalafil and alcohol both lower blood pressure. Therefore, combining tadalafil with alcohol may cause excessive drops in blood pressure and cause dizziness, headaches, and increased heart rate.

PDE5 inhibitors may affect platelet function and therefore prolong bleeding. Tadalafil should be used cautiously in patients with bleeding disorders or active ulcers. Tadalafil should not be combined with Adcirca (another form of tadalafil) or other PDE5 inhibitors, for example, vardenafil (Levitra) or sildenafil (Viagra, Revatio).

PREGNANCY: Tadalafil is not approved for use in women.

NURSING MOTHERS: Tadalafil is not approved for women and has not been evaluated in women who are breastfeeding.

SIDE EFFECTS: The most common side effects of tadalafil are facial flushing (reddening), headaches, stomach upset, diarrhea, flu-like symptoms, and nausea. Tadalafil also may cause low blood pressure, blurred vision and changes in color vision, and abnormal ejaculation. Tadalafil has been associated with prolonged erections or priapism (painful erections lasting more than 6 hours). Patients should seek immediate medical help if they experience an erection lasting more than 4 hours. Use of tadalafil, most often in patients with pre-existing heart disease, has been associated with chest pain, heart attacks, death, strokes, palpitations, and increased heart rate. Rare cases of sudden loss of hearing have been reported with phosphodiesterase inhibitors such as tadalafil, sometimes associated with ringing in the ears and dizziness. If changes in hearing occur, patients should stop their tadalafil and seek immediate medical attention. Phosphodiesterase-5 inhibitors have been associated rarely with non-arteritic anterior ischemic optic neuropathy (NAION), a condition which causes decreased vision and may lead to blindness. Patients should stop use of all PDE5 inhibitors and seek medical attention if they experience sudden loss of vision in one or both eyes.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 8/8/2013


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