This PDF deals with important catchpoints regarding the use of 5-alpha reductase inhibitors, their safety and efficacy stats, and important counselling tips.

1. 5-ALPHA REDUCTASE INHIBITORS: A BRIEF
INSIGHT
GENERIC NAMES:
Dutasteride, finasteride
BASIC INFORMATION:
Habit forming? No
Is prescription required? Yes
Available as generic? Yes, for some
Drug class Dihydrotestosterone inhibitor
USES:
 Treatment of BPH (Benign prostatic hypertrophy) in men with enlarged
prostate
 Treatment of male pattern hair loss in men.
DOSAGE & USAGE INFORMATION:
How to take drug?  Available as either tablet or
capsule
 Swallow with liquid
 Drug can be taken regardless of
meals
When to take?  Once a day or a directed-on
prescription
What happens if you forget a dose?  Resume regular schedule
 Avoid dose-doubling
What does the drug do (MOA)?  Dihydrotestosterone 
hormone required for
development of BPH
 Drugs  inhibit 5-alpha
reductase enzyme  prevent
conversion of testosterone to

2. dihydrotestosterone.
Time for maximal drug effects  For BPH: 6 months
 For hair loss: 3 months at
least.
POSSIBLE ADRs AND HOW TO DEAL WITH THEM:
SYMPTOMS WHAT TO DO?
Rare Impotence, reduced libido,
breast changes (enlargement,
tenderness, lumps, pain,
discharge from nipples),
depressed mood, rash
Continue medication
Consult physician or
pharmacist
Infrequent Reduced volume of ejaculation,
headache, dizziness
Continue medication
Consult physician or
pharmacist
Common Nothing significant
Life-
threatening
Nothing significant
WARNINGS & PRECAUTIONS:
Don’t take drug, if….  You are allergic to dutasteride
or finasteride
 Allergic reactions may occur
Consult physician or pharmacist,
if…
 You have had prostate cancer
OR didn’t do a blood test yet to
check for prostate cancer
 Your sexual partner is pregnant
or may become pregnant
 You have a liver disorder
 You have reduced urinary flow
 You have large residual urinary
volume (bladder dysfunction)
Drug discontinuation  Never discontinue without
medical advice
 Consult doctor if adverse
effects like problems with
libido, ejaculation and orgasm

3. continue after drug stoppage.
ADVICE FOR SPECIAL POPULATIONS:
CONDITION ADVICE
Geriatrics No special problems expected
Pregnancy Not recommended for women
Breastfeeding, lactation, nursing
mothers
Not recommended for women
Infants & children up to age 18 Not recommended
Prolonged drug use Consult with physician or pharmacist
regarding need for follow-up medical
examinations or laboratory studies to
check drug effectiveness.
Skin & sunlight No special problems expected
Driving, piloting or hazardous
work
No special problems expected
POSSIBLE DRUG INTERACTIONS:
DRUG-DRUG INTERACTIONS
Drugs involved Effect observed
Enzyme inhibitors Unknown effect with dutasteride
Consult physician or pharmacist.
DRUG-FOOD/SUBSTANCES INTERACTIONS
Food/substance involved Effect observed
Alcohol None expected
Beverages Grapefruit juice Consult doctor or pharmacist
Foods Grapefruit Consult doctor or pharmacist
Cocaine Unknown effects. Avoid
Marijuana Seek medical advice
Tobacco None expected.
IMPORTANT DRUG CATCHPOINTS:

4.  Inform any doctor, dentist or pharmacist if you are taking this medicine
beforehand.
 Drug  may affect results of PSA (Prostate specific antigen) test, used for
diagnosis of prostate cancer.
 Drug  should be continued as per physician/pharmacist opinion.
 Drug  may increase risk of high-grade prostate cancer  consult
physician/pharmacist about your risks of the same.
 Drug  leads to male infertility and/ or poor semen quality. Once drug is
stopped  sexual side-effects improve and return to normal.
 Avoid donating blood at least 6 months after drug use cessation.
DR. VISHNU R.
NAIR