Drugs can be classified based on their therapeutic effects, such as: Analgesics: Pain relievers. Antipyretics: Fever reducers. Antibiotics: Infection fighters. Antihypertensives: Blood pressure regulators. Sedatives and Hypnotics: Sleep-inducing drugs. Antidepressants: Mood stabilizers.

Drug action is based on the interaction between drugs and specific receptors in the body, leading to a biological response. Drugs can act as agonists (activating receptors) or antagonists (blocking receptor activity), and their effect depends on factors like dosage, pharmacokinetics, and individual variability.

Pharmacology is essential in healthcare for the safe and effective use of drugs. It helps healthcare providers understand how drugs work, their side effects, interactions, and the appropriate dosages. This knowledge is crucial for prescribing medications that improve patient outcomes and prevent adverse effects.