To answer your questions:
1) I am not aware of these side effects being associated with Propecia. I looked at the PDR, and it does not list these side effects on the drug label.
2) Taking a lower dose will reduce side effects, but also would reduce effectiveness.
3) Here is the side effective profile from the PDR:
>10%:
Endocrine & metabolic: Impotence (19%; combination therapy 23%), libido decreased (10%; combination therapy 12%)
Neuromuscular & skeletal: Weakness (5%; combination therapy 17%)
1% to 10%:
Cardiovascular: Postural hypotension (9%; combination therapy 18%), edema (1%, combination therapy 3%)
Central nervous system: Dizziness (7%; combination therapy 23%), somnolence (2%; combination therapy 3%)
Genitourinary: Ejaculation disturbances (7%; combination therapy 14%), decreased volume of ejaculate
Endocrine & metabolic: Gynecomastia (2%)
Respiratory: Dyspnea (1%; combination therapy 2%), rhinitis (1%; combination therapy 2%)
<1%, postmarketing and/or case reports: Hypersensitivity (pruritus, rash, urticaria, swelling of face/lips); breast tenderness, breast enlargement, breast cancer (males), prostate cancer (high grade), testicular pain
4) DHT production is necessary for the development of secondary sexual characteristics in males at puberty. In adulthood, DHT helps in maintaining normal prostate function.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
kevinmd_b