The three legal classes
| Class | Where it can be sold | Supervision |
|---|---|---|
| General Sale List (GSL) | Any lockable retail premises, for example a supermarket | No pharmacist needed, but pack sizes are limited |
| Pharmacy (P) | Registered pharmacy only | Sale must be by or under the supervision of a pharmacist |
| Prescription-Only Medicine (POM) | Registered pharmacy, against a valid prescription | Supplied in accordance with a prescription, PGD or other lawful route |
A medicine is POM by default unless it has been specifically exempted. The hierarchy runs POM, then P, then GSL, with controls loosening as you move down. Anything that is not a POM and not a GSL medicine is, by default, a P medicine.
Sale versus supply
A sale is a transaction for money, for example an over-the-counter purchase. A supply is providing a medicine, for example against a prescription or a PGD, which may not involve a direct sale to the patient. Both are regulated, and the legal class determines the lawful route.
Supervision
Supervision means the pharmacist is aware of the transaction and is in a position to intervene and advise. The pharmacist does not have to make the sale personally, but must be physically present and able to stop or influence it. A P medicine cannot be sold if the pharmacist is absent from the premises.
Reclassification (switching)
Medicines can be reclassified to widen access, usually moving POM to P, or P to GSL. Examples that have switched from POM to P over the years include some doses of omeprazole, sumatriptan for migraine, and emergency hormonal contraception. Reclassification follows an assessment that the medicine is safe enough for wider supply.
📌 Key facts to remember
- •A medicine is POM unless exempted; the default is the most restrictive class.
- •Anything that is neither POM nor GSL is a P medicine.
- •P medicines require pharmacist supervision and a registered pharmacy.
- •GSL medicines can be sold from any lockable premises, within pack-size limits.
- •Reclassification usually loosens control (POM to P, P to GSL).
⚠️ Watch the quantity and strength
Some medicines change class with pack size or strength. The same drug can be GSL in a small pack and P in a larger one, or P at a low strength and POM at a higher one, so always check both the medicine and the quantity being sold.
🧠 The legal framework
The supply of human medicines in the UK is governed mainly by the Human Medicines Regulations 2012, which replaced most of the Medicines Act 1968. These set out the three legal classes and who may sell or supply them. The MHRA licenses medicines and decides their classification, while the GPhC regulates pharmacy professionals and premises. Controlled drugs sit under a separate framework (the Misuse of Drugs legislation) on top of this.
Harder scenarios
A supermarket with no pharmacist on site wants to sell a 32-tablet pack of a pharmacy (P) medicine. Is this lawful?
Answer: No. A P medicine can only be sold from a registered pharmacy by or under the supervision of a pharmacist, regardless of the pack size. The supermarket can only sell GSL medicines.
Test yourself
A customer wants to buy a medicine while the pharmacist has stepped out of the building. Can a P medicine be sold?
Answer: No. A P medicine must be sold by or under the supervision of a pharmacist, who must be present. GSL items may still be sold.
By default, what legal class is a new medicine placed in?
Answer: Prescription-only medicine (POM). It stays POM unless specifically exempted to P or GSL.
A medicine is neither a POM nor on the general sale list. What class is it?
Answer: A pharmacy (P) medicine, by default.