Cialis (tadalafil) provides for up to 36 hours of efficiency and helps men suffering from erectile dysfunction to complete sexual intercourse with no problems whatsoever. This is one of most popular erectile dysfunction treatments that works in most cases and helps men of any age achieve a stable erection they need to have sex. Before you start your treatment, let your doctor know if you are currently using any nitrate-based drugs or if you are allergic to tadalafil. Both these factors will prevent you from safely taking Cialis. Any other medications you are using or intend to use while on Cialis also need to be reported to your health care provider. The following ones are especially important to mention: isoniazid, seizure medications, erythromycin, conivaptan, clarithromycin, heart or blood pressure medications, antidepressants, telithromycin, dalfopristin, imatinib, antifungal medications, rifampin, HIV/AIDS medicines, diclofenac, and doxazosin. Any other mineral supplements or vitamins also need to be reported to make sure taking Cialis is safe for you. Cialis is tolerated very well, and just a few side effects are possible. Flushing, stomach upset, back pain, nasal stuffiness, pain in arms or legs, headache, dizziness, vision changes, and muscle pain are considered to be normal and should not prevent you from using Cialis and having sex unless you have been recommended to abstain from sexual activity because it can put too much strain on your heart. If while having sex you experience chest pain, tingling or numbness, dizziness and some other symptoms of the kind - stop taking Cialis and contact your doctor right away. Make sure you always take the exact dose of this medicine prescribed and never exceed it, even if you think Cialis is not efficient for you. The following symptoms may indicate an overdose: stuffy or runny nose, chest pain, indigestion, pain in the back, erection that lasts longer than 4 hours, heartburn, headache, and flushing. Seek emergency medical help if you have taken too much of Cialis and have the symptoms mentioned above. At least 24 hours are supposed to pass between two doses of this medicine. Such conditions as congestive heart failure, bleeding disorder, liver disease, kidney disease, chest pain, stomach ulcer, high or low blood pressure, retinitis pigmentosa, heart disease, a history of a heart attack, and a recent history of a stroke are to be reported to your doctor to make sure your treatment is safe and there are no interactions possible.