Medications for benign prostatic hyperplasia (BPH) are used to treat urinary symptoms of an enlarged prostate. They generally work by relaxing muscles in the prostate or bladder or by shrinking the prostate. Common classes include alpha blockers and 5-alpha reductase inhibitors. Alpha blockers like tamsulosin (Flomax) and doxazosin (Cardura) are usually taken as oral pills. 5-alpha reductase inhibitors, such as finasteride (Proscar) and dutasteride (Avodart), are also taken orally. Combination medications like dutasteride / tamsulosin (Jalyn) offer a dual approach to managing BPH.