CH 251, Respiratory Drugs, Skeletal Muscle Relaxants, Antihypertensive Drugs, Angina Pectoris, Cardiac Arrhythmias, Congestive Heart Failure, Coagulation Disorders and Hyperlipidia, Endocrine Pharmacology, Male and Female Hormones, Thyroid and Parathyroid, Diabetes

Final Exam Objectives

MALE AND FEMALE HORMONES

Male hormones: androgens eg testosterone

Female hormones: estrogen eg estradiol and progestins eg progesterone

Produced in the gonads (androgens in the testes and female hormones in the ovaries)

ANDROGENS

Physiological effects

1) Development of male characteristics: Begins in the uterus when testes produce testosterone.  Androgen production becomes more prominent during puberty when male characteristics are developed eg body hair, increased skeletal muscle, voice change etc.

2) Spermatogenesis: sperm production

Pharmacological use

Specific agents: eg methyltestosterone, Stanozolol, testosterone (see  table 30.1).

Route of delivery can be oral or intramuscular.

Drugs can be given for anabolic (tissue increase) or androgenic effect (male sexual characteristics) – the distinction is not clear

1. Replacement therapy: when endogenous synthesis of testosterone is impaired.

2. Catabolic states: given to patients who need muscle strength eg after surgery or trauma

3. Delayed puberty: to accelerate puberty

4. Breast cancer: hormone sensitive tumors can be treated by androgens

5. Anemia: androgens stimulate hemoglobin synthesis

6. Hereditary angioedema: defect in clotting factors.  Androgens act on liver to restore synthesis clotting factors.

Adverse effects

In women: masuculinization, hirsutism (excess hair, deepening of voice)

In men: bladder irritation, breast swelling and  soreness

In children: may cause accelerated sexual maturation and impaired bone development.

The above are more common for prolonged use of hormones and sometimes symptoms may go away once the treatment is halted.  Long term side effects may cause liver damage.

Antiandrogens

Help to reduce androgen production eg in prostate cancer. 

finasteride: inhibits conversion of testosterone to dihydrotestosterone which accelerates growth of prostate gland.

Flutamide: antagonist for androgen receptor eg in treatment of hirsutism.

Androgen abuse

Anabolic steroids used to enhance athletic performance eg in weight lifting, body building etc.

Table 30.2 for examples of anabolic steroids in the market.

Consider if:

These drugs work?

What are the adverse effects?

How does this affect a competitive sport?

Long term abuse can lead to:

1. Liver damage: hepatic tumors, can be fatal
2. Blood lipid profile: decreases HDL leading to arteriosclerosis, lesions and stroke.
3. Hypertension: anabolic steroids can have salt and water retaining properties
4. Glucose metabolism: causes insulin resistance
5. Impaired skeletal growth: especially in young children exposed to early drug abuse scene.
6. Habits: increased aggressive behavior, mood swings and violence
7. Damage to the reproductive system

Estrogen and progesterone 

Physiological effect

At puberty there are series of hormonal events which stimulate ovaries to produce estrogen and progestin which initiate maturation of reproductive system and secondary characteristics in women.

Estrogen is responsible for changes in organs and internal reproductive organs eg uterus, oviducts, breast development and changes in the skeletal system.

Progesterone is important in maintaining pregnancy.

Pharmacological uses

1. Replacement therapy: during menopause or  women who have had ovariectomy.  Estrogens help prevent osteoporosis.  Estrogen therapy also decreases risk of coronary heart disease.

2. Hypogonadism: when hormone production is low.

3. Failure of ovarian development: given during puberty.

4. Menstrual irregularities

5. Endometriosis: growth of uterine like tissue in the pelvic region. Exogenous hormones help to suppress bleeding from the tissue and inhibit their growth.

6. Carcinoma: treat metastatic breast cancer in men and post-menopausal women.

Adverse effects

Nausea

Swelling of feet

Higher doses may cause cardiovascular problems

Progesterone may cause abnormal blood clotting

Antiestrogens

Androgens and progesterone decrease the effect of estrogen. They are antagonists. Eg clomiphene is a fertility drug.

Contraceptives

Most are oral. Most contain a fixed amount of estrogen and progesterone in a pill. Usually taken for 3 weeks and for one week a blank pill is given, works best.

If there is only progestin then its less effective eg Norplant.

Only estrogen are the morning after pills.

Oral contraceptives inhibit ovulation and development of endometrium.

Adverse effects of contraceptives: Nausea, dizziness, loss of appetite etc.