Medicines can be dangerous for carriage, particularly cytotoxic drugs for cancer treatments etc. Some medicines are flammable. Typical UN Numbers are 1851, 3248, and 3249. They are treated exactly as any other dangerous goods unless SP 601 applies. These goods are out of scope if in packages prepared for retail sale or personal consumption.
Many problems with carriage of drugs relate to returns to pharmacies for disposal, as the pharmacist may take drugs out of the packaging and mix them. Good practice is to avoid mixing, and to keep drugs in their original packaging until they reach the disposal site.