Drugs function by altering the existing bodily functions in disease and health; they do not produce any new thing in the body. Essentially, drugs either stimulate or inhibit existing physiological activities, kill disease causing germs, destroy cancer cells, replenish endogenous hormones and correct their deficiencies, and correct deficiencies of vitamins, minerals, essential amino acids, essential fatty acids and anti-oxidants.

1. z
How Do the Medicinal Drugs
Work ?
Dr. Ashok Kumar Batham,
M.B.,B.S., M.D., D.C.R.,
Dr. Batham’s On-line Clinic
Phone: +91 93280 18777
Email: ashokpharmacol@gmail.Com

2. z
Mechanisms of action of medicinal drugs
 Drugs function by altering the existing bodily functions in disease and
health;
 Drugs do not produce any new thing in the body.
 Essentially, drugs either stimulate or inhibit existing physiological
activities, kill disease causing germs, destroy cancer cells, replenish
endogenous hormones and correct their deficiencies, and correct
deficiencies of vitamins, minerals, essential amino acids, essential fatty
acids and anti-oxidants.
Dr.AshokKumarBatham
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3. z
STIMULATION OF EXISTING BODY
FUNCTIONS
ELEVATION OF BLOOD PRESSURE:
 Noradrenaline and Dopamine are used to treat hypotensive states, like shock
due to major blood loss caused by trauma or surgery or sepsis
STIMULATION OF THE HEART:
 Adrenaline is used to treat Cardiac Arrest, a near-death situation wherein heart
stops beating, due to drowning, anesthetic accident in operation theatre,
myocardial infarction or heart attack
 Atropine is used to treat slow heart rate or bradycardia
 Digoxin is used to increase the force of contraction of heart in the treatment of
heart failure
Dr.AshokKumarBatham
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4. z
STIMULATION OF EXISTING BODY
FUNCTIONS (contd.)
STIMULATION OF CONTRACTIONS OF UTERUS (WOMB) during labor or child-birth
(Oxytocin infusion is used in labor rooms to facilitate child-birth).
IMMUNOSTIMULATION - Enhancement of Body’s Immunity against specific infections:
 Use of vaccines for Small Pox, Chicken Pox, Measles, Mumps, Rubella,
Poliomyelitis, Pneumonia, Influenza etc. etc.,
 Anti-serums (Antisera) - for Tetanus, Rabies, Snake-bite
 Immuno-stimulant drugs – GM CSF (Granulocyte Macrophage Colony
Stimulating factor)
Dr.AshokKumarBatham
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5. z
INHIBITION OR DEPRESSION OF EXCESSIVE ACTIVITY
OF CERTAIN SYSTEMS
Inhibition or depression of excessive activity of certain systems:
 Lowering of Blood Pressure by a number of drugs, such as, Nifedipine, Amlodipine, Enalapril,
Lisinopril, Prazosin, Atenolol etc. to treat high blood pressure (hypertension),
 Reduction of Heart Rate by a number of drugs, like Propranolol, Metoprolol, Bisoprolol etc. to
manage certain heart conditions characterized by rapid heart rate and disturbed rhythmic
beating of heart,
 Reduction of overactivity of urinary bladder, by certain drugs like, Oxybutynin, Trospium etc. to
treat Over Active Bladder (OAB),
 Reduction of excessive bowel or intestinal movements to treat diarrhea (frequent passage of
loose stools) with the use of Loperamide, Atropine, Diphenoxylate etc.,
Dr.AshokKumarBatham
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6. z
INHIBITION OR DEPRESSION OF EXCESSIVE ACTIVITY
OF CERTAIN SYSTEMS (contd.)
Inhibition or depression of excessive activity of certain systems:
 lowering and normalization of body temperature in fever by antipyretics like
Aspirin and Paracetamol,
 lowering of excessive levels of some substances, like lipids in blood with the
use of lipid-lowering drugs, like Atorvastatin; and glucose with Glibenclamide,
Glimepiride, Metformin etc.,
 inhibition of excessive activities of certain body hormones, for example,
thyroid hormone by antithyroid drugs in hyperthyroidism or Grave’s disease,
growth hormone by somatostatin analogs in gigantism and acromegaly etc. etc.,
 inhibiting excessive secretion of certain body chemicals, such as,
hydrochloric acid in stomach, by Cimetidine, Ranitidine, Omeprazole,
Esomeprazole, Pantoprazole etc. etc.,
Dr.AshokKumarBatham
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7. z
REPLACEMENT OR REPLENISHMENT OF DEFICIENT
BODY HORMONES
Replacement or replenishment of deficient body hormones:
 Insulin by Insulin injection in diabetes mellitus
 Thyroid hormone, thyroxine in hypothyroidism
 Corticosteroids in Addison’s disease
Dr.AshokKumarBatham
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8. z
REPLENISHMENT OF DEFICIENT NUTRIENTS
 Vitamins: Vitamin C in scurvy, Vitamin D in Rickets and
Osteomalacia, Vitamin A in Night Blindness, Vitamin B1 in
Beri Beri, Vitamin B12 and Folic Acid in Anemia etc.
 Minerals: Iron in Anemia, Calcium in Osteoporosis, Zinc in
taste and growth disorders etc.
 Fatty acids and amino acids: in nutritional deficiencies
 Proteins: in nutritional deficiencies
Dr.AshokKumarBatham
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9. z
DESTRUCTION OF DISEASE
PRODUCING GERMS AND PARASITES
Antimicrobials, Antibacterials, Antibiotics, Antivirals, Anti-fungals,
Anti-parasitic Drugs, exemplified by Amoxycillin, Ciprofloxacin,
Acyclovir, Amantadine, Griseofulvin, Fluconazole, Quinine,
Chloroquine, Albendazole etc. kill the disease producing germs and
parasites
Huge Range of Infections and Infestations caused by Bacteria,
Viruses, Fungi, Plasmodia, Worms, Ticks, Lice etc. are treated and
cured.
Dr.AshokKumarBatham
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10. z
DESTRUCTION OF CANCER CELLS
Destruction of cancer cells through cytotoxic action by cancer
chemotherapy drugs like Cyclophosphamide, Cytarabine,
Doxorubicin, Paclitaxel, Vincristine, Vinblastine etc. in the treatment
of cancer.
Dr.AshokKumarBatham
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11. z
CONTROL OVER DISEASE PROCESSES
 Control of inflammation (pain, swelling, redness, fever, and loss of
function of the affected part or the whole body) with the use of
steroidal and non-steroidal anti-inflammatory drugs,
 Reversal of allergic reactions (redness, flare, wheal, mucosal
swelling, itching, excessive lacrimation, sneezing, runny-nose) with
the use of anti-histamines, like loratadine, cetirizine and other
agents, and
 Prevention of blood clotting (Thrombosis) by aspirin.
Dr.AshokKumarBatham
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12. z
MODULATION OF CERTAIN BODY
MECHANISMS
Immunomodulation and disease modification by drugs like-
Leflunomide, Teriflunomide, Gold Salts, Penicillamine
for the treatment of some auto-immune disease:
 Rheumatoid Arthritis,
 Systemic Lupus Erythematosus,
 Multiple Sclerosis etc.
Dr.AshokKumarBatham
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13. z
BLOCKING CERTAIN ENDOGENOUS
FACTORS
Blocking Certain Endogenous Factors:
Epidermal Tissue Growth Factor (TGF) by Cetuximab and
Panitumumab, for the treatment of Head & Neck Cancers
and Metastatic Colorectal Cancer.
Dr.AshokKumarBatham
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14. z
BLOCKADE OF CERTAIN
NEUROTRANSMITTERS
Blockade of function of certain neurotransmitters at their
receptors, for example:
Adrenaline by Propranolol,
Acetylcholine by Atropine,
Dopamine by Risperidone.
Dr.AshokKumarBatham
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15. z
MIMICRY OF FUNCTIONS OF CERTAIN
NEUROTRANSMITTERS AT THEIR RECEPTORS
Mimicry of functions of certain neurotransmitters at their
receptors, for example:
 Adrenergic receptors by Ephedrine,
 Cholinergic receptors by Physostigmine, and
 Dopaminergic receptors by Levodopa.
Dr.AshokKumarBatham
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16. z
Thank You
Dr.AshokKumarBatham
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