1. Pharmacology UG-Course Touqeer Ahmed PhD 19 th February, 2015 Atta-ur-Rahman School of Applied Biosciences National University of Sciences and Technology

2. Pharmacology Course Contents Introduction to Pharmacology – Drug-Receptor Interactions and Pharmacodynamics – Pharmacokinetics Nervous System Drugs – The Autonomic Nervous System – Cholinergic and Adrenergic drugs – Anxiolytic, Hypnotic, Central Nervous System Stimulants, Antidepressant Drugs, and antiepileptics Cardiovascular Drugs – Antiarrhythmic Drugs, Antianginal Drugs, Antihypertensive Drugs, Drugs Affecting The Blood Drugs affecting the endocrine system – Oral Hypoglycemic Drugs Drugs affecting respiratory and gastrointestinal systems Principles of antimicrobial therapy – Inhibitors of Cell Wall Synthesis – Protein Synthesis Inhibitors – Folate Antagonists – Quinolones, and Urinary Tract Antiseptics – Antimycobacterial Drugs – Antifungal Drugs – Antiprotozoal Drugs – Antiviral Drugs – Anticancer Drugs – Immunosuppressants Anti-inflammatory drugs and autocoids

3. Recommended Books

4. Pharmacology Evaluation System Assignment 10 Quiz20 First Sessional10 Second Sessional10 Final Exams (Terminal Exams)50

5. Introduction to Pharmacology

6. Pharmacology Today

7. Basic Concepts in Pharmacology

8. Pharmacology (Derived from a Greek word) What is a drug? – For the purposes of this book, a drug can be defined as a chemical substance of known structure, other than a nutrient or an essential dietary ingredient, 1 which, when administered to a living organism, produces a biological effect. – To count as a drug, the substance must be administered, rather than released by physiological mechanisms. Many substances, such as insulin or thyroxine, are endogenous hormones but are also drugs when they are administered intentionally. What is a medicine? – A medicine is a chemical preparation, which usually but not necessarily contains one or more drugs, administered with the intention of producing a therapeutic (healing/recovery from disease) effect. – Medicines usually contain other substances (excipients, stabilisers, solvents, etc.) besides the active drug, to make them more convenient to use. 1 Like most definitions, this one has its limits. For example, there are a number of essential dietary constituents, such as iron and various vitamins, that are used as drugs/medicines.

9. Pharmacodynamics: is the study of the biochemical and physiological effects of drugs on the body or on microorganisms or parasites within or on the body and the mechanisms of drug action and the relationship between drug concentration and effect. Pharmacokinetics: is the study of what the body does to a drug Basic Concepts in Pharmacology

10. Protein targets for drug binding F our main kinds of regulatory protein are commonly involved as primary drug targets, namely: 1.receptors (activate signaling pathways) 3.enzymes 2. carrier molecules (transporters) 4.ion channels. Basic Concepts in Pharmacology Agonists and antagonists Agonists, which 'activate' the receptors, and antagonists, which combine at the same site without causing activation, and block the effect of agonists on that receptor.

11. Basic Concepts in Pharmacology THE BINDING OF DRUGS TO RECEPTORS – Why do we plot it on the Log scale?

12. Agonist: An agonist binds to a receptor and produces a biologic response. An agonist may mimic the response of the endogenous ligand on the receptor, or it may elicit a different response from the receptor and its transduction mechanism. Full agonists: If a drug binds to a receptor and produces a maximal biologic response that mimics the response to the endogenous ligand (e.g. phenylephrine is an agonist at α1-adrenoceptors) Partial agonists Partial agonists have efficacies (intrinsic activities) greater than zero but less than that of a full agonist. Even if all the receptors are occupied, partial agonists cannot produce an Emax of as great a magnitude as that of a full agonist. (e.g. aripiprazole, used to treat schizophrenia) – A unique feature of these drugs is that, under appropriate conditions, a partial agonist may act as an antagonist of a full agonist. Inverse agonists: Some receptors show a spontaneous conversion from R to R* in the absence of agonist (that is, they can be active without the presence of agonist). These receptors, thus, show a constitutive activity that is part of the baseline response measured in the absence of drug. Inverse agonists, unlike full agonists, stabilize the inactive R form. (some scientist categorize these along with antagonist ) Agonists (Types)

13. Agonists (Quantifying Agonism) Drugs have two observable properties in biological systems: – Potency Potency is controlled by four factors: 1.Receptor density in a tissue 2.Efficiency of the stimulus-response mechanisms present by default in the tissue 3.Affinity of the drug for its receptor 4.Efficacy – Efficacy/Magnitude of effect (when a biological response is produced) The advantage of using efficacy is that this property depends solely on efficacy, whereas potency is a mixed function of both affinity and efficacy