Cialis (Tadalafil) is the first tablet for erectile dysfunction (ED) that gives you up to 36 hours to choose the moment that's right for you and your partner. CIALIS works fast - within 30 minutes in some patients - and can work up to 36 hours. That means you and your partner can be spontaneous, responding to each other sexually when the moment is right. Of course your results may vary so talk to your doctor today to see if CIALIS is right for you. Tablets Chemical Name: TADALAFIL ( tah-DA-la-fil) Possible Uses of This Medication Tadalafil is used to treat male sexual function problems (impotence or erectile dysfunction) by blocking a certain enzyme (phosphodiesterase-PDE5) in the body. More info... Before using The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. More info... How to take this medication This drug is taken by mouth as needed, at least 30 minutes before sexual activity with or without food; or use as directed by your doctor. More info... Cautions Before taking tadalafil, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. More info... Possible side effects Headache, stomach upset, back pain, muscle pain, nasal stuffiness, flushing, pain in arms or legs, dizziness, or vision changes may occur. More info... Drug interactions This drug should not be used with the following medications because very serious (possibly fatal) interactions may occur: certain alpha-blocker medication (alfuzosin, doxazosin, prazosin, terazosin), nitrates (e.g., nitroglycerin, isosorbide), nitroprusside (or any "nitric oxide donor" drugs), recreational drugs called "poppers" containing amyl or butyl nitrite. More info... Missed Dose Not applicable. Storage Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. More info... Other Information DO NOT SHARE THIS MEDICINE with others for whom it was not prescribed.