INDICATIONS

Finast prevents the conversion of testosterone to dihydrotestosterone (DHT) in the body. DHT is involved in the development of benign prostatic hyperplasia (BPH).
Finast (Propecia) is used for the treatment of male pattern hair loss. Finast (Proscar) is used to treat symptoms of benign prostatic hyperplasia (BPH) in men with an enlarged prostate. 
Finast may also be used for other purposes.

INSTRUCTIONS

Take this medication exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label.
Take this medicine with a full glass of water. 
Finast can be taken with or without food. Take the medicine at the same time each day.
To be sure this medication is helping your condition and not causing harmful effects, your blood may need to be tested often. Your doctor will also test your prostate specific antigen (PSA) to check for prostate cancer.

STORAGE

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

SAFETY INFORMATION

Finast should never be taken by a woman or a child.To make sure you can safely take finast, tell your doctor if you have any of these other conditions:

liver disease, or abnormal liver enzyme tests;

prostate cancer;

a bladder muscle disorder;

stricture of your urethra;

if you are unable to urinate; or

if you have ever had an allergic reaction to a similar medicine called dutasteride (Avodart).
 Using finast may increase your risk of developing prostate cancer.

SIDE EFFECTS

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you notice any breast lumps, pain, nipple discharge, or other breast changes. These may be signs of male breast cancer.

Less serious side effects may include:

impotence, loss of interest in sex, or trouble having an orgasm;

abnormal ejaculation;

swelling in your hands or feet;

swelling or tenderness in your breasts;

dizziness, weakness;

feeling like you might pass out;

headache;

runny nose; or

skin rash.

This is not a complete list of side effects and others may occur.

Please find the full description of Finast at Drugs.com and general information at Wikipedia