Do not take this medicine with any of the following medications:
-nitrates like amyl nitrite, isosorbide dinitrate, isosorbide mononitrate, nitroglycerin
-other medicines for erectile dysfunction like avanafil, sildenafil, vardenafil
-other tadalafil products (Cialis)
-riociguat

This medicine may also interact with the following medications:
-certain drugs for high blood pressure
-certain drugs for the treatment of HIV infection or AIDS
-certain drugs used for fungal or yeast infections, like fluconazole, itraconazole, ketoconazole, and voriconazole
-certain drugs used for seizures like carbamazepine, phenytoin, and phenobarbital
-grapefruit juice
-macrolide antibiotics like clarithromycin, erythromycin, troleandomycin
-medicines for prostate problems
-rifabutin, rifampin or rifapentine

They need to know if you have any of these conditions:
-eye or vision problems, including a rare inherited eye disease called retinitis pigmentosa
-heart disease, angina, a history of heart attack, irregular heart beats, or other heart problems
-high or low blood pressure
-kidney disease
-liver disease
-pulmonary veno-occlusive disease (PVOD)
-stomach ulcers
-stroke
-an unusual or allergic reaction to tadalafil, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Do not change the dose of your medicine without asking your doctor. Call your doctor if your medication is not working for you. This may be a sign that your condition has become worse.

If you notice any changes in your vision while taking this drug, call your doctor or health care professional as soon as possible. Stop using this medicine and call your health care provider right away if you have a loss of sight in one or both eyes.

For males, contact you doctor or health care professional right away if an erection lasts longer than 4 hours or if it becomes painful. This may be a sign of serious problem and must be treated right away to prevent permanent damage.

If you experience symptoms of nausea, dizziness, chest pain, or arm pain after taking this medicine, you should discuss the episode with your doctor or health care professional as soon as possible.

Do not drink more than 4 alcohol-containing drinks in a short period of time when taking this medicine. When taken in excess, alcohol can increase your chances of getting a headache or getting dizzy, increasing your heart rate or lowering your blood pressure.

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.