Chemical tools can prevent, control, or cure disease. Medication is any substance or combination of substances used to treat or prevent disease, relieve symptoms, or modify physiological function for therapeutic benefit.

Medications include prescription drugs, over-the-counter products, and certain biologics. They are formulated as tablets, capsules, injections, inhalers, creams, and other delivery forms. Effectiveness depends on correct drug selection, dose, timing, and adherence. Interactions with food, other drugs, and disease states alter response.

Safe medication use requires clear labeling, patient understanding, and systems that reduce prescribing and administration errors. Pharmacists play a central role in counseling and checking for problems. Regular review of medication lists prevents accumulation of unnecessary or harmful agents.

• Substance used to treat, prevent, or alleviate disease
• Available in multiple formulations and routes
• Requires correct selection, dosing, and adherence
• Safety depends on systems and patient education