How many classes of drugs in the world?

There are numerous classes of drugs, typically categorized based on their pharmacological effects, chemical structure, or therapeutic use. Common classes include analgesics, antibiotics, antidepressants, antipsychotics, and anti-inflammatory drugs, among others. The exact number of drug classes can vary, but they are generally grouped into several dozen major categories, which can further be subdivided into more specific subclasses. Overall, the classification of drugs is extensive and continuously evolving with advances in medical science.