Definition:- a drug is an externally administered substance which modifies or affects chemical reactions in the body.
Beneficial effects of drugs
- For pain relief – drugs like aspirin, paracetamol and morphine.
- For treatment of diseases – diseases caused by bacteria, such as syphilis are treated with drugs called Antibiotics. A well-known antibiotic is penicillin.
- For its mood influencing effect. – Useful for treating patients with emotional disorders such as depression.