Read our editorial process. Some examples of nitrates are nitroglycerin Nitro-Dur, Nitrostat, others , isosorbide mononitrate Monoket and isosorbide dinitrate Bidil. Its effects often last for 4 to 5 hours. This medicine also works best when you take it an hour before sex on an empty stomach. A phone or video consultation is sometimes required for legal purposes. ED medications can cause side effects, and it’s crucial to have access to a medical provider if needed. Taking generic ED medications is an effective way to save money without sacrificing quality. · The approved dosages of Cialis for ED, BPH symptoms, or both, are between mg and 20 mg a day or as needed. Dosages higher than 20 mg a day haven’t been studied, and it’s not known what. It contains the same active ingredient as Levitra and can begin working in about 15 minutes. Viagra takes around 30 minutes to become effective and lasts about 4 hours. Cialis lasts much longer. View more medications. Cialis Cialis® is a type of medication known as a PDE5 inhibitor that is used to treat erectile dysfunction and benign prostatic hyperplasia. It comes in several different doses and can be taken either as-needed or daily for erectile dysfunction. Check Prices What we offer Generic Cialis Generic Cialis is called.