In the UK, medication preparations are approved for use for licensed indications by The Medicines and Healthcare products Regulatory Agency (MHRA).  Medicines are classified by the MHRA into one of the following legal categories:

  • General Sales List (GSL) medicines can be bought in any retail outlet without the supervision of a pharmacist
  • Pharmacy Only (P) medicines are restricted for purchase through a registered pharmacy and under the supervision of a pharmacist
  • Prescription Only Medication (POM) can only be legally obtained against a valid prescription issued by a doctor, dentist or other suitably qualified prescriber e.g. nurse, pharmacist

Controlled drugs are mainly POM medicines which are subject to strict legal controls to reduce potential abuse, diversion or harm.

To learn more about the MHRA, follow this link:
About MHRA


The Misuse of Drugs Regulations 2001

The regulation permits the possession and supply of controlled drugs for legitimate purposes.  Controlled drugs (CDs) are categorised into schedules, specifying the requirements which govern activities such as prescribing, record keeping and storage:

  • Schedule 1 CDs have no medicinal use, and a Home Office license is required for their production, possession or supply e.g. LSD, raw opium
  • Schedule 2 CDs include potent opioids, major stimulants and cannabis-based products for medicinal use e.g. morphine, ketamine, cannabidiol
  • Schedule 2 CDs are subject to requirements relating to prescription writing, safe custody and record keeping
  • Schedule 3 CDs include barbiturates, weaker opioids, certain benzodiazepines and others e.g. phenobarbital, buprenorphine, tramadol, temazepam, gabapentin and pregabalin
  • Schedule 3 CDs are only subject to requirements relating to prescription writing and not all require safe custody, however, Trusts may choose to enforce safe custody requirements (refer to your local CD policy)
  • Schedule 4 part 1 CDs include other benzodiazepines, non-benzodiazepine hypnotics and Sativex® and are subject to minimal control, with only Sativex® requiring a record in a CD register
  • Schedule 4 part 2 CDs include androgenic and anabolic steroids and growth hormone drugs able to enhance physical performance; they are also subject to minimal control
  • Schedule 5 CDs include low strength preparations of codeine, pholcodine or morphine and are practically exempt from all requirements, aside keeping invoices related to their purchase


Misuse of Drug Act, 1971

The Act prohibits certain activities in relation to controlled drugs.  Controlled drugs are categorised into class A, B or C according to harm when misused.  The higher the class of drug, the stricter the penalty for possession, supply and production:

  • Class A drugs include heroin, cocaine, ecstasy and LSD
  • Class B drugs include amphetamines, such as speed, barbiturates and cannabis
  • Class C drugs include, tranquillisers, benzodiazepines and anabolic steroids

Please see link below for further information around penalties attached to these drugs:


The Yellow Card Scheme and Black Triangle Drugs

The MHRA also monitor the safety of all medicines once they are licensed and marketed, this is known as pharmacovigilance.  The inverted black triangle symbol (▼) is used in the BNF for newly licensed medicines and vaccines, which indicates they are under intensive monitoring by the MHRA.  All suspected adverse reactions (whether minor or serious) for medicines with this symbol should be reported by healthcare professionals through the Yellow Card Scheme. For all other medicines and vaccines (without a black triangle), only serious suspected adverse reactions should be reported, even if the adverse reaction is well documented.

Link to yellow card reporting:


Yellow Card Scheme Mobile App: Available for download from the Apple App Store or Google Play Store.

The MHRA produce a monthly Drug Safety Update newsletter for healthcare staff, with clinical advice on the safe use of medicines.  To sign up for updates follow this link:
MHRA Drug Safety Update Newsletter

Now watch this short video on why it is important to report suspected adverse drug reactions to the MHRA: 


Unlicensed Medicine or ‘Off-Label” Use

An unlicensed medicine is one that is not licensed in the UK by the MHRA, whereas off-label use is when a licensed medicine is used outside of its license.  There are occasions when no licensed medicine will meet a patient’s clinical needs, examples of this include:

  • Prescribing a medicine for a different indication to that it is licensed for
  • Prescribing a medicine at a higher dose than licensed
  • Prescribing a medicine in children when it is licensed for adults only
  • Prescribing a licensed medicine imported from another country, but not licensed in the UK
  • This is not commonly done, but sometimes necessary, for example due to a supply shortage of a licensed preparation or if it is not available in the UK at all

Before an unlicensed medicine or an off-label medicine is prescribed:

  • There must be no suitable licensed alternative that will meet the patient’s clinical needs
  • There is sufficient evidence of safety and efficacy for the use of the medicine
  • The Trust must approve the use of unlicensed medicines within their organisation
  • The patient or their carer must be informed that the medicine is unlicensed, by the prescriber and the rationale for treatment.