What Are Drugs?

Drugs are substances that alter the body’s function. They can be used for medical treatment or have harmful effectsif misused.

💡 Key Concept: Some drugs are medicinal, while others are recreational or illegal.

Types of Drugs

How Do Drugs Affect the Body?

✔ Medicinal drugs treat illnesses and improve health.
✔ Recreational drugs affect the nervous system, causing changes in mood, behaviour, and addiction.
✔ Illegal drugs can be highly addictive and damage organs like the liver, heart, and brain.

💡 Key Fact: Nicotine, alcohol, and caffeine are legal but can still be addictive.

Alcohol & Smoking – The Risks

1️⃣ Alcohol (Ethanol) 🍷

✔ Slows brain function (depressant).
✔ Causes liver disease and brain damage.
✔ Can lead to addiction (alcoholism).

💡 Key Risk: Drinking alcohol during pregnancy can cause fetal alcohol syndrome, affecting the baby’s growth.

2️⃣ Smoking (Nicotine & Tobacco) 🚬

✔ Nicotine is addictive and raises heart rate.
✔ Smoking damages lungs and increases risk of lung cancer & heart disease.
✔ Tobacco contains carcinogens (cancer-causing chemicals).

💡 Key Risk: Smoking during pregnancy reduces oxygen supply to the baby, increasing risk of low birth weight.

Drug Testing & Development

Before drugs are approved for use, they go through strict testing:

1️⃣ Preclinical Testing – Tested on cells and animals to check safety.
2️⃣ Clinical Trials (Human Testing) –
✔ Low doses on healthy volunteers (safety).
✔ Tests on patients to check effectiveness.
✔ Double-blind trials to avoid bias.

💡 Example: Penicillin was discovered by Alexander Fleming and became the first antibiotic to treat bacterial infections.