T 27 20mg pill makes the blood flow easily into the penis, which helps to make an erection. Best medicine for erectile dysfunction without side Effects. The pill with imprint T 27 (White, Round, 7mm) has been identified as Sildenafil Citrate 20 mg and is used for Erectile Dysfunction, and Pulmonary Arterial Hypertension. It belongs to the drug classes agents for pulmonary hypertension, impotence agents and is not a controlled substance.