What makes a medicine a controlled drug?
Controlled drugs are medicines with extra legal controls because they can be misused, diverted or cause dependence. The Misuse of Drugs Act 1971 makes it an offence to possess or supply them except as allowed by regulations. The Misuse of Drugs Regulations 2001 then say who may prescribe, supply, possess and administer them, and place each drug in one of five schedules.
Many controlled drugs, such as morphine, oxycodone, fentanyl and midazolam, are also high-risk in ordinary clinical use, because an overdose can cause fatal breathing problems. So controlled drug rules protect against two things at once: harm to patients and diversion of stock.
What are the five schedules of controlled drugs?
The schedule decides the rules for prescribing, storage, record keeping and destruction. Schedule 1 is the most tightly controlled and Schedule 5 the least.
| Schedule | Examples | Main controls |
|---|---|---|
| 1 | Drugs with little or no recognised medicinal use, such as LSD | Possession only under a Home Office licence. Not used in routine care |
| 2 | Morphine, diamorphine, oxycodone, fentanyl, methadone, pethidine | Full prescription requirements, safe custody in a locked CD cabinet, register entries, witnessed destruction where the regulations require it |
| 3 | Midazolam, temazepam, buprenorphine, tramadol, gabapentin, pregabalin, phenobarbital | Full prescription requirements. Safe custody applies to some (such as temazepam and buprenorphine) but not others. No legal register requirement, though many organisations require one |
| 4 | Most benzodiazepines such as diazepam and lorazepam (Part 1); anabolic steroids (Part 2) | No legal safe custody or register requirement. Prescriptions valid for 28 days |
| 5 | Low-strength preparations such as some codeine and morphine products | Minimal controls. Invoices kept. Some sold over the counter in pharmacies |
What must a Schedule 2 or 3 prescription include?
- The patient's full name and address.
- The drug name, form and strength.
- The dose, with clear directions.
- The total quantity in both words and figures.
- The prescriber's signature and address.
Prescriptions for Schedule 2, 3 and 4 drugs are valid for 28 days from the appropriate date. National guidance advises that the quantity should not normally exceed 30 days' treatment unless the prescriber can justify more. Pharmacists must not supply against a prescription that fails the legal requirements, although some minor technical errors can be amended by the pharmacist where the regulations allow.
Registered midwives have specific legal exemptions that allow them to possess and administer certain controlled drugs, such as pethidine, morphine and diamorphine, in their professional practice. They must follow their employer's policy on supply, storage, recording and return.
How should controlled drugs be stored?
Drugs subject to safe custody must be kept in a locked cabinet or safe that meets the Misuse of Drugs (Safe Custody) Regulations 1973. On a ward, the CD cabinet should hold only controlled drugs and any other items local policy allows, never money or valuables.
- Keys are held by the nurse or midwife in charge, or a registered professional they delegate to, and kept separate from other keys.
- Missing keys are escalated immediately in line with local policy.
- Deliveries are checked against the order, seals checked, and stock entered in the register straight away. Do not leave stock unlocked while waiting to book it in.
- Refrigerated controlled drugs go in a locked fridge, kept apart from other medicines as policy directs.
- Patients' own controlled drugs remain their property and are recorded and stored separately from ward stock.
What are the rules for the controlled drug register?
The regulations require organisations and pharmacies that hold Schedule 1 and 2 stock to keep a register, with entries in chronological order and a separate register or section for each class of drug. NICE guideline NG46 and local policies extend this good practice to wards, which normally keep a ward CD record book for stock and each administration. Registers may be paper or a secure electronic system. Legally required registers must be kept for at least two years from the last entry, and many organisations keep them longer.
- One page per product: Use a separate page or section for each drug, form and strength.
- Record on the day: Make entries in order, at the time of the transaction or as soon as possible that day, in indelible ink or the electronic system.
- Never alter an entry: Do not cross out heavily, use correction fluid or write over. Correct a mistake with a dated, signed marginal note or footnote that leaves the original readable.
- Keep a running balance: Record the new balance after every entry and check it against the physical stock.
- Only sign what you saw: Never pre-sign and never witness retrospectively. Your signature is a legal record.
A nurse writes the wrong balance. She covers it with correction fluid, writes the right number over the top and initials it.
A nurse writes the wrong balance. She leaves it legible, adds an asterisk and a footnote: balance incorrectly recorded as 9, correct balance 8, error identified at 14:20 on the date. She and her witness sign and date the correction, and she tells the nurse in charge.
How should controlled drugs be administered and witnessed?
Most hospitals and care organisations require two people for controlled drug administration, usually two registered professionals, or one registered professional and another trained person where local policy allows. Both should be present from start to finish.
- Check the prescription: patient, drug, dose, route, frequency, last dose and any 24-hour maximum. For opioids, confirm immediate-release or modified-release and current opioid use.
- Check the stock together: drug, strength, form and expiry, and that the balance matches the register before removing the dose.
- Prepare the dose together, recording any amount wasted from a part-used ampoule.
- Both go to the patient, confirm identity and allergies, and the witness sees the dose given.
- Record on the chart and in the register immediately, with both signatures and the new balance.
Used fentanyl patches still contain active drug. Fold them sticky sides together and dispose of them as local policy directs. When applying a new patch, check for old ones that may have been left on.
Returns and destruction
Wards usually return unwanted stock to pharmacy rather than destroying it. Where a Schedule 2 register is legally required, stock may only be destroyed in front of an authorised witness, such as someone authorised by the Controlled Drugs Accountable Officer. Destruction of Schedule 3 and 4 stock should be witnessed by a second member of staff as good practice. Partly used ampoules at the bedside are wasted in front of the witness and recorded.
What should you do if the CD stock does not match the register?
Most discrepancies have an innocent cause: an arithmetic slip, a missed entry, a dose given but not recorded, or a breakage. A few reflect diversion. You do not need to decide which. Your job is to report it promptly and help find the cause.
- Recheck together: Recount with a colleague and review recent entries, charts and records. Look for arithmetic errors and stock on the wrong page or shelf.
- Report now: If it cannot be resolved, tell the nurse in charge or responsible pharmacist and the manager before the end of the shift.
- Involve pharmacy: Pharmacy will help investigate and escalate unresolved discrepancies to the Controlled Drugs Accountable Officer under local policy.
- Complete an incident report: Unresolved discrepancies and suspected diversion are reported to the Accountable Officer, who may share concerns with the Local Intelligence Network or the police.
- Record honestly: Never adjust the balance to make it match. Correct it only once the cause is understood, with a clear note and authorisation.
How do regulators view controlled drug concerns?
Each registrant is personally accountable for what they sign. The NMC Code requires accurate records, honesty and openness, and the GPhC standards require pharmacy professionals to act with honesty and integrity and to speak up. Concerns usually fall into two groups. Poor practice, such as missed signatures or incorrect records, can often be remedied with training, supervised practice and audit. Dishonesty, such as false entries or theft, is far more serious and may involve the police.
On a busy night, a colleague asks Grace to countersign the CD book for oral morphine given an hour earlier. Grace was with another patient but signs because she trusts her colleague. The morning stock check finds 10 mL missing. Grace tells the nurse in charge at once that she did not witness the dose, takes advice from her union and gives an honest statement. She completes CD training, now politely refuses to sign for anything she has not seen and offers to help with the next dose instead, and her manager audits her entries for three months.
If you suspect a colleague is diverting controlled drugs or is impaired at work, raise it with your manager, pharmacy, your Freedom to Speak Up Guardian or the Accountable Officer. Describe facts, not conclusions. If you are being investigated, get advice from your defence organisation, trade union or legal representative before giving a statement. If you are personally struggling with substance use, confidential help is available through NHS Practitioner Health or your GP.
Strengthening your controlled drugs practice
Good controlled drug practice comes down to a few habits: store securely, record at the time, witness only what you see, check stock properly and report discrepancies straight away. Know your local policy as well as the law, because most day-to-day rules come from local procedures.
If you would like structured learning, perhaps after a discrepancy or as part of revalidation, our course Controlled Drugs: Safe Handling and Accountability covers the schedules, register entries, administration, discrepancies and a reflective case study with a remediation plan. Use it alongside your organisation's CD policy and advice from your pharmacy team.
Frequently asked questions
What is the difference between Schedule 2 and Schedule 3 controlled drugs?
Both have full prescription requirements. Schedule 2 drugs, such as morphine and oxycodone, must be kept in a CD cabinet and recorded in a register. Schedule 3 drugs, such as midazolam and tramadol, have no legal register requirement and only some need safe custody, although many organisations apply stricter local rules.
How do you correct a mistake in a controlled drug register?
Never cross it out heavily, overwrite it or use correction fluid. Leave the original entry legible and add a dated, signed marginal note or footnote explaining the error and the correct information. Your witness should also sign, and you should tell the person in charge in line with local policy.
Does midazolam need to be stored in the CD cupboard?
Midazolam is a Schedule 3 controlled drug that is exempt from the legal safe custody requirements. However, many hospitals store it in the CD cabinet and record it in the register by local policy. Always follow your organisation's controlled drugs policy, which may be stricter than the law.
How long must a controlled drug register be kept?
Registers required by the Misuse of Drugs Regulations must be kept for at least two years from the date of the last entry. Many NHS organisations keep them for longer under their records policy. Check your local policy for ward record books and other non-statutory records.
How long is a controlled drug prescription valid for?
Prescriptions for Schedule 2, 3 and 4 controlled drugs are valid for 28 days from the appropriate date. National guidance also advises that quantities should not normally exceed 30 days' treatment unless the prescriber can justify a larger supply.
What should I do if I find a controlled drug discrepancy?
Recheck with a colleague, looking for arithmetic or recording errors. If it cannot be resolved, report it immediately to the nurse in charge or pharmacist and your manager, involve pharmacy, and complete an incident report. Never adjust the balance to hide the difference.
Can I countersign a controlled drug entry if I did not see the dose given?
No. A witness signature confirms you saw the drug checked, prepared and given. Signing retrospectively makes the record inaccurate and removes a key safety check. Politely refuse and offer to witness the next dose properly. If pressured, raise it with the person in charge.
Related courses
Controlled Drugs: Safe Handling and Accountability
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Sources and further reading
- Misuse of Drugs Regulations 2001. legislation.gov.uk.
- Controlled Drugs (Supervision of Management and Use) Regulations 2013. legislation.gov.uk.
- Controlled drugs: safe use and management (NG46). National Institute for Health and Care Excellence.
- Controlled drugs in care homes. Care Quality Commission.
- Professional guidance on the safe and secure handling of medicines. Royal Pharmaceutical Society.
- The Code: Professional standards of practice and behaviour for nurses, midwives and nursing associates. Nursing and Midwifery Council.
- Standards for pharmacy professionals. General Pharmaceutical Council.
Practitioner Insight is an independent education provider. It is not affiliated with or endorsed by the GMC, MPTS, NMC, HCPC, GPhC or any NHS organisation, and this information is not legal advice. If you have been referred to a regulator, speak to your defence organisation, trade union or legal representative.
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