Lesson Summary

The text discusses various aspects of pharmacology, including pharmacokinetics tolerance and pharmacodynamic tolerance. Key points include:

• Pharmacokinetics tolerance involves changes in drug levels at the site of action, leading to decreased drug effect.
• Pharmacodynamic tolerance describes decreased sensitivity or receptor number at the site of action without changes in drug levels.
• Tachyphylaxis signifies a rapid decrease in drug response.
• Cross-tolerance refers to tolerance developing to related drugs.

Adverse drug reactions, harmful effects of drugs, are discussed, including different types:

• Type A reactions involve intolerance, side effects, overdose, and toxicity.
• Type B reactions are bizarre and dose-independent, like immune-based reactions or idiosyncrasy.
• Other types include drug-induced diseases, pharmacogenetic disorders, and allergic reactions.

Furthermore, the text covers drug-induced effects, pharmacogenetic disorders caused by abnormal genes, and allergic reactions initiated by drugs acting as antigens. Drug allergies and types based on antibodies and reactions are explored.

Pharmacology, the study of drugs and their effects on the body, involves:

• Understanding how drugs alter body functions to produce biological effects.
• Encompasses pharmacodynamics and pharmacokinetics.

The dose-response relationship is illustrated by graded and all-or-none dose-response curves:

• Efficacy - maximal effect induced by a drug.
• Potency - dose needed to produce a specific response.

Pharmacology also discusses mechanisms of drug actions:

• Receptor-mediated and non-receptor-mediated mechanisms.
• Ligand-receptor interactions and types of agonists and antagonists.

Signal transduction mechanisms, like those involving ion channels and G-proteins, play a crucial role in drug-cellular responses. Understanding these mechanisms aids in comprehending drug actions on physiological effects. Moreover, drug actions extend to various physiological targets, including enzymes, cell membranes, genetic processes, and chemical reactions.

Tolerance in pharmacology refers to the gradual decrease in drug effectiveness with continuous use; mechanisms such as enzyme induction play a role in managing drug responses over time.