Rye grass pollen extract has been shown to shrink the prostate gland in at least one study, according to WebMD. It also helps relax the muscles of the urethra while helping the bladder muscles contract, which can cut down on dribbling after urination and the need to urinate at night.
Many other home remedies help alleviate the symptoms of a swollen prostate gland, although they don't shrink the prostate. Avoiding drinking anything for an hour or two before bedtime, limiting caffeine and alcohol intake, urinating at regular intervals throughout the day, and staying active are all recommended by Mayo Clinic to deal with the symptoms of an enlarged prostate. Urinating as soon as the urge is felt and completely emptying the bladder by urinating twice in a row, known as double voiding, is also recommended.
African wild potato extract and African plum extract are also known to alleviate urinary symptoms, states WebMD, as is plant-based beta-sitosterols. Mayo Clinic adds that no studies have definitively found any herbal remedy to work for an enlarged prostate, and that the FDA has not approved any herbal medications for treatment. Still, they are probably safe to try for up to six months, WebMD notes.