UK Medicine Classes: GSL, P, and POM

• There are three legal classes of medicinal products in the UK.
• These are General Sale Medicines (GSL), Pharmacy Medicines (P), and Prescription-Only Medicines (POM).
• Over the counter (OTC) refers to medicines available for purchase without a prescription, including GSL and P medicines.
• Pharmacy only (PO) medicines are legally classified as GSL, but sale is restricted to pharmacies by the manufacturer and should not be confused with P medicines.

Medicines Switching Classes

• Medicines can be reclassified by the Medicines and Healthcare products Regulatory Agency (MHRA).
• The usual switch is from POM to P, then to GSL.
• Restrictions on reclassified medicines may include indication, pack size, strength, or route of administration.
• Declassifying medicines widens patient access and increases pharmacist expertise, but the pharmacy profession is not always in favor of switches from P to GSL.
• Government is keen to declassify due to the self-care agenda and reduced costs to the NHS.
• The Royal Pharmaceutical Society (RPS) provides guidance on the sale of recently switched products.
• Products may rarely move from GSL to P to POM.
• Recent POM to P switches include:
  • Sildenafil (2018)
  • Fexofenadine (2020)
  • Desogestrel (2021)
  • Topical vaginal oestrogen (2022)
  • Tadalafil (2023)

Human Medicines Regulations 2012

• Chapter 2 regulates dealings in medicinal products.
• The basic principle, set out in regulation 220, is that medicinal products can only be sold or supplied in circumstances corresponding to retail sale from registered pharmacies, under the supervision of a pharmacist.
• Unless they are products on a general sales list or otherwise subject to an exception.

General Sales Medicines (GSL)

• GSL medicines are defined in the Human Medicines Regulations (HMR) 2012 as products that are not POM or P.
• GSL medicines must be covered by a marketing authorization making them available for general sale.
• These medicines can be sold or supplied with reasonable safety without the supervision of a pharmacist.
• Some medicines may be GSL only in smaller pack sizes, lower strengths, for certain indications, or in a specific form, which requires careful selling.

Retail Sale of GSL Medicines

• GSL medicines may be sold at registered pharmacies or anywhere else if certain conditions are met.
• The premises must be able to be closed to exclude the public.
• The product must be pre-packaged and not opened.
• If included in Schedule 15, the product must be sold according to its requirements.
• GSL medicines may be sold from vending machines if the conditions are complied with.
• A responsible pharmacist must be signed in when sold from a pharmacy.
• Exception: Supply of medicinal products may occur in the event or anticipation of a pandemic disease.
• GSL sale is permitted from aircraft and trains if the sale is made by the operator or commander.
• The product must have been pre-packaged in a container elsewhere.
• The product must be stored in a part of the aircraft or train that can be closed to exclude the public.

Products That Are Not General Sale

• Products with greater than a specified maximum daily dose of vitamin A or vitamin D are not GSL.
• The following, unless classified as GSL, are not for general sale:
  • Eye ointments
  • Anthelmintics
  • Parenteral administration
  • Enemas
  • Irrigation of wounds, bladder, vagina, or rectum
  • Preparations of aloxiprin or aspirin for children

OTC Stimulant Laxatives

• MHRA changed the legal status due to misuse and abuse concerns with stimulant laxatives.
• Stimulant laxatives include senna/sennosides, bisacodyl, and sodium picosulfate, while co-danthramer and co-danthrusate are POM products.
• As of August 2020, regulations include pack size restrictions, revised age recommendations, and new safety warnings.
• Smaller packs are available as GSL for short-term, occasional constipation in adults only.
• Max pack size is two short treatment courses, such as 20 standard-strength tablets, 10 maximum-strength tablets, or 100ml solution/syrup, while larger packs (up to 100 tablets) are now P medicines.
• GSL products are licensed for use in patients 18 years or older.
• Stimulant laxatives should not be used in children under 12 without advice from a prescriber.
• Products for children aged 12–17 can only be supplied under the supervision of a pharmacist, i.e., they are P medicines.
• Patient information leaflets advise that overuse of stimulant laxatives may be harmful due to fluid and electrolyte disturbances and potential disruption of intestinal function.
• Warnings appear on product packaging and state the products do not aid in weight loss to support awareness.
• The RPS has further information on this topic.