If you become pregnant while taking tadalafil, call your doctor. If you are taking tadalafil to treat PAH or BPH, follow your doctor’s directions and the guidelines in this paragraph. Tell your doctor if any of these symptoms are severe or do not go away: headache. Continue to take tadalafil even if you feel well. Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medicine.Tadalafil is a generic medication for ED, and a person can expect to pay in the region of $ each month for this drug. The brand-name version of tadalafil is Cialis, which can sometimes cost. Tadalafil – STADA T20 – 20 Milligramm. Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction, benign prostatic hyperplasia, and pulmonary arterial hypertension. It is taken by mouth. Onset is typically within half an hour and the duration is up to 36 hours. Common side effects include headache, muscle pain, . Tadalafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). In combination with sexual stimulation, tadalafil works by increasing blood flow to the penis to.