Drug Classification Short Notes

Drug Classification A drug is a substance taken into the body to produce some desired pharmacological result. This can be taken in a positive or negative way. All substances are poisons, there is none that is not a poison. The right dose differentiates a poison from a remedy. However, not all poisons can be used therapeutically, e.g., beryllium, mercury, thallium rich, dioxins, etc. The toxicologist needs to be aware not only of the drugs themselves, but also of the products of biotransformation after ingestion (metabolites). Medicines are combination of drugs (Active Pharmaceutical Ingredients – API) and inert ingredients. Paracetamol is the drug or API, but a cold remedy containing paracetamol, e.g., Lemsip is a medicine. Inert ingredients may include bulking agents, binding agents, flavourings, etc. depending on the properties of the API. Also, often some function material that allows ‘slow release’ etc. of the drug. Classification depends on context and can change over time. For example, cocaine was used as a local anaesthetic in toothache drugs and dentistry. Cocaine was then described as a CNS stimulant and was used as an ingredient in Coca-Cola. Now cocaine is used illegally as a recreational drug, especially when the addictive effects become clear. There are 5 classifications of drugs: • Acidic, basic or neutral • Source (natural, semi-synthetic, synthetic) • Physiological consequence • Classification based on use • Controlled substances (Misuse of Drugs Act classification) Any drug can be classified in more than one way. These classifications are not arbitrary.