Misuse of Drugs Act 1975: Controlled Drug Schedules, Safe Custody and Records

The Misuse of Drugs Act 1975

The Misuse of Drugs Act 1975 (MDA) is the principal legislation governing controlled drugs in New Zealand. It classifies controlled substances by their risk of harm and establishes requirements for storage, prescribing, supply, record-keeping, and destruction. The MDA operates alongside the Medicines Act 1981 — controlled drugs are both prescription medicines under the Medicines Act and scheduled substances under the MDA.

Drug Classification Under the MDA

The MDA classifies controlled drugs into five schedules based on their potential for misuse and relative harmfulness.

Class A substances are deemed to pose the greatest risk and their possession, supply, and manufacture are absolutely prohibited. Examples include heroin (diamorphine), methamphetamine, LSD, cocaine (in most forms), and MDMA. Penalties for dealing Class A drugs carry maximum sentences of life imprisonment.

Class B substances include opioid analgesics such as morphine, oxycodone, fentanyl, methadone, and pethidine. These drugs have legitimate medical uses but are tightly controlled. Class B also includes cannabis and amphetamines. Prescriptions for Class B controlled drugs must be handwritten in ink, include quantity in both words and figures, and bear the prescriber's handwritten signature.

Class C substances include some opioids (codeine >5 mg per dose unit), benzodiazepines (diazepam, lorazepam, clonazepam), ketamine, anabolic steroids, and GHB. Prescriptions for Class C CDs may be computer-generated but must be signed by hand.

Schedule 1 (prohibited substances) and further schedules under the MDA govern specific exemptions — for example, codeine at concentrations ≤5 mg per dose unit may be sold as a restricted medicine under the Medicines Act.

Prescription Requirements for Controlled Drugs

A controlled drug prescription must be written or printed, hand-signed, and include: prescriber name, address, qualifications, and signature in ink; patient full name, address, and date of birth; the drug name, strength, dose form, and directions; and the total quantity expressed in both words and figures (e.g., "thirty (30) tablets"). The date must be included and CD prescriptions are valid for 90 days. Only one dispensing per prescription is permitted unless the prescription specifies repeat dispensing.

Safe Custody Requirements

Controlled drugs must be stored in a locked metal cabinet that is fixed to the wall or floor of the pharmacy. The cabinet must be constructed to prevent unauthorised access. Keys must be held by the pharmacist-in-charge or a designated pharmacist. Class B CDs (Schedule 2 equivalents) have the highest safe custody requirements. Class C CDs may have more flexible storage depending on local regulations, though a locked controlled drug cabinet remains best practice.

Record-Keeping Requirements

Pharmacies must maintain a CD register (controlled drug register) in which all receipts and supplies of Class B and Class C CDs are recorded. Entries must be made immediately upon receipt or supply, in chronological order, in indelible ink. No erasures are permitted — corrections must be made by a footnote or marginal note. The register must be retained for at least seven years. Each entry must include the date, name and quantity of the drug, the supplier or recipient (including the patient's name and address), the prescriber's name, and the balance remaining after each transaction.

Destruction of Controlled Drugs

Expired or unwanted CDs cannot simply be discarded. They must be destroyed in the presence of an authorised witness — usually a pharmacist employed by the District Health Board or Ministry of Health. An authorised form must be completed recording the drug, quantity, date, and witnesses. CDs returned by patients should be stored securely until formal destruction can be arranged.