Can Cialis be used with other treatments for impotence? Your doctor will probably tell you not to take tadalafil if you are taking nitrates. What alternatives can I use for erectile dysfunction? In , Pfizer scientists discovered that sildenafil, which also inhibits the PDE5 enzyme, caused penile erection in males participating in a clinical study of a heart medicine. The FDA has also approved tadalafil for treatment of both benign prostatic hypertrophy and erectile dysfunction where the two conditions co-exist. Cialis is not recommended for people taking any form of nitroglycerin because the combination may lower blood pressure to an unsafe level. Tadalafil Cialis is used to treat erectile dysfunction ED, impotence; inability to get or keep an erection , and the symptoms of benign prostatic hyperplasia BPH; an enlarged prostate which include difficulty urinating hesitation, dribbling, weak stream, and incomplete bladder emptying , painful urination, and urinary frequency and urgency in adult men.headache. indigestion. back pain. muscle pain. flushing. stuffy nose. Patients who get back pain and muscle aches usually get them 12 to 24 hours after taking Cialis and these usually go away by. Tadalafil (Cialis) is used to treat erectile dysfunction (ED, impotence; inability to get or keep an erection), and the symptoms of benign prostatic hyperplasia (BPH; an enlarged prostate) which include difficulty urinating (hesitation, dribbling, weak stream, and incomplete bladder emptying), painful urination, and urinary frequency and urgency in adult men. Cialis lasts up to 36 hours in the body, while Viagra lasts 4–6 hours in the body. Both are taken 30 minutes before sex. Cialis can cause limb pain, while Viagra can cause vision change, rash.