Androgens are male sex hormones that cause the development of secondary sex characteristics in males. The primary androgen is testosterone, which is produced in the testes and regulated by LH from the pituitary gland. Testosterone promotes the growth of male sex organs and secondary sex characteristics at puberty such as facial and body hair growth, deepening of the voice, and increased muscle and bone growth. It works by binding to androgen receptors and enhancing protein synthesis. Common androgen preparations are used to treat conditions like testicular failure, aging-related low testosterone, and erectile dysfunction. Phosphodiesterase type 5 inhibitors like sildenafil are a treatment for erectile dysfunction by enhancing the effects of nitric oxide

1. ANDROGENS
By
Dr.S.KAMESHWARAN.,M.Pharm.,Ph.D.,
Associate Professor, Excel College of Pharmacy
Komarapalayam, Tamilnadu

2. ADROGENS
Androgen is a male sex hormone
“ANDROGENS ARE THE SUBSTANCE WHICH
CAUSE DEVELOPMENT OF SECONDERY SEX
CHARACTERS IN THE IMPOTENT MALE”
Also called androgenic hormone or testoid,
It is a steroid hormone, which stimulates or
controls the development and maintenance of
male characteristics
This includes the activity of the accessory male
sex organs and development of male secondary
sex characteristics.

3. Androgens were first discovered in 1936.
The primary and most well-known androgen is
Testosterone. Dihydrotestosterone (DHT) and
androstenedione are less known
DHT
In the embryo life causes differentiation of penis,
scrotum and prostate.
Later in life it contributes to male balding,
prostate growth and sebaceous gland activity.
Testosterone produced by the testis in male,
Testes are responsible for the male characters.

4. NATURAL ANDROGENS
TESTES of adult male produce 5-12g of
testosterone per day
Adrenal cortex produces small quantity of
androgens, so they are called as weak
androgens.

5. REGULATION OF SECRETION:
LH FROM ANTERIOR PITUITARY
↓
STIMULATE THE SECRETION OF
TESTOSTERONE FROM INTERSTITIAL CELLS
OF THE TESTES
↓5 REDUCTACE
DI HYDRO TESTOSTERONE
↓
ACT ON TARGET TISSUE
Secretion of testosterone is controlled by feedback
inhibition.

6. ACTIONS
SEX ORGAN & SECONDARY SEX CHARACTERS
Testosterone involved in the development of sex organ
& secondary sex characters
It is responsible for all changes occur in a boy at puberty
which includes
GROWTH OF GENITAL:
Growth of Penis, Scrotum, Seminal vesicle, Prostate.
GROWTH OF HAIR:
Growth of hair in Pubic, Axillary, Beard, Moustache &
Body, Male porter of its distribution.
Thickening of skin and become greasy due to increase
the activity of sebaceous glands.
Larynx grows- voice deepens
Behavioral effect increases physical vigor aggressiveness,
penile erection, male libido appears.

7. SKELETON AND SKELETAL MUSCLE:
Growth in boys, less in girls.
Rapid bone growth both thickness and length.
Promote muscle building.
Increase the appetite.
ERYTHROPOISIS:
Increases erythropoiesis by increasing
erythropoietin production.

8. MECHANISM OF ACTION:
DIHYDRO TESTOSTERONE
↓
BINDS MORE AVIDLY WITH THE CYTOPLASMIC
RECEPTOR
↓
FORMS A COMPLEX WHICH IS MORE ACTIVE
↓
WHICH COMBINES WITH DNA
↓
DNA TRANSCRIPTION IS ENHANCED
↓
PROTEIN SYNTHESIS
↓
BIOLOGICAL EFFECT.

9. PHARMACOKINETICS:
Testosterone inactive orally due to high first
pass metabolism
Esters of testosterone are always administered
After hydrolysis the active free form of drug is
released
98% protein binding
Metabolized in liver
Excreted through kidney

10. ADR:
Excess body hair
Menstrual irregularities in women
Acne in male
Painful erection
Oligozoospermia
edema
Hepatic carcinoma
Gynaecomastia

11. PREPARATIONS:
– Methyl testosterone
– Fluoxymesterone
They are orally active compounds.
Metabolized slowly and have long duration of
action.
USES:
Testicular failure
Hypopituitarism
Ageing

12. ANABOLIC STEROIDS:
Nandrolone
Oxymetholone
Stanozolol
Methandienone

13. DRUGS FOR ERECTILE DYSFUNCTION
ERECTILE DYSFUNCTION:
“It is inability of men to attain and maintain an
erect penis with sufficient rigidity to allow
sexual intercourse”
Occurs mainly in post middle age i.e. 65.
Causes :
 Vascular,
 Neurogenic,
 Hormonal,
 Pharmacological or Psychological,

14. ERECTION MECHANISM
SEXUAL EXCITEMENT
↓
NITRIC OXIDE RELEASED FROM NONADRENERGIC
NONCHOLINERGIC (NANC) NERVES
↓
RELAXATION OF SMOOTH MUSCLE IN CORPUS
CAVERNOSUM
↓
BLOOD FLOWS IN TO THE PENIS (CORPUS
CAVERNOSUM)
↓
THEY FILL IT UP WITH BLOOD
↓
MAKING THE PENIS RIGID, ELONGATED AND ERECT.

15. ANDROGENS:
Parenteral testosterone esters /Transdermal
testosterone therapy is used
Effective only when loss of libido & ED due to
androgen deficiency.
PHOSPHO DIESTERASE - 5 INHIBITORS:
(PDE-5 INHIBITORS)
Eg:-
 SILDENAFIL
 VARDENAFIL
 TADALAFILL

16. SILDENAFIL:
Orally active,
Introduced in India in 2000,
act by selectively inhibiting PDE-5,
Enhance nitric oxide action in corpus
cavernosum.

17. MECHANISM OF ACTION:
SEXUAL EXCIEMENT
↓
RELEASE OF NITRICOXIDE (NO)
↓
STIMULATE GUANYLATE CYCLASE (GC)
↓promote synthesis of
cGMP FROM GUANOSINE TRI PHOSPHATE (GTP)
↓
cGMP CAUSE SMOOTH MUSCLE RELAXATION IN PENIS
↓
MORE BLOOD ENTERSIN TO CORPORA SPONGIOSUM AND
CAVERNOSA
↓
ERECTION
PHOSPHO DI ESTERASE-5 (PDE-5)↓  SILDENAFIL
DEACTIVATE cGMP
↓
RELAXATION

18. PHARMACOKINETICS:
Oral bio availability is 40%
Peak blood levels attained in 1-2 hours
Metabolized in liver by CYP3A4 enzyme
T1/2 in > 65 years men 4 hours
Actual dose 50mg
>65 years – 25mg
ADR:
Vasodilatation
Headache
Nasal congestion
Dizziness
Flushing and fall in B.P
Loose motions.

19. THANK U