Medicinal Cannabis NZ Guide

Pregnancy, breastfeeding and young people

If you are pregnant, planning a pregnancy, breastfeeding, or under 25, the safe default with medicinal cannabis is the same: do not start it, and if you are already prescribed it, talk to…

Pregnancy, breastfeeding and young people
Medicinal Cannabis NZ Guide , CC BY 4.0 via Wikimedia Commons

If you are pregnant, planning a pregnancy, breastfeeding, or under 25, the safe default with medicinal cannabis is the same: do not start it, and if you are already prescribed it, talk to your prescriber before stopping or changing anything. The guidance below gives you the precautionary reasoning, the evidence behind it, and a practical decision rule you can use with your doctor or pharmacist.

The short answer

Under New Zealand’s Medicinal Cannabis Scheme, medicinal cannabis products are available only on a doctor’s order from a medical practitioner. They must meet GMP standards and be approved by the Ministry of Health (Medsafe, 2020). For pregnancy, breastfeeding, and people under 25, the data is thin and precautionary. The NZ Formulary and the New Zealand Ministry of Health advise against use in pregnancy and while breastfeeding unless a clinician decides the potential benefit clearly outweighs the risk. For young people, the research is limited, and prescribing is a specialist judgement. The material below gives you a decision rule, a checklist, and the exact questions to ask a prescriber.

The decision rule in one sentence

If you are pregnant, planning pregnancy, breastfeeding, or under 25 and considering medicinal cannabis, the default is no; the only exception is a formal script from a doctor who has documented the specific clinical justification and the absence of safer alternatives.

What the New Zealand law says

Under the Misuse of Drugs Act 1975 and the Misuse of Drugs (Medicinal Cannabis) Regulations 2019, medicinal cannabis is a prescription medicine. The Medicinal Cannabis Scheme, administered by the Ministry of Health’s Medicinal Cannabis Agency (MCA), sets product standards and licensing for cultivation, manufacture and supply.

From 1 April 2020, the scheme allows medical practitioners to prescribe cannabis-based items that meet GMP standards and have been notified to Medsafe. The item must be a manufactured pharmaceutical, not raw plant material you bought from a non-pharmacy source. The raw flower is available, but only as a prescribed, pharmacy-dispensed product; it is not a general licence to smoke cannabis.

For pregnancy and breastfeeding, the NZ Formulary (New Zealand Formulary, 2024) advises against medicinal cannabis unless the prescriber has considered the risks and documented a clear clinical rationale. The Ministry of Health’s position, updated in 2023, is that no cannabis item is approved for use in pregnancy or while breastfeeding because of the absence of safety data and the known risks of THC to the developing brain.

For young people (under 18), the NZ Formulary notes that the research base is limited to a few conditions, mainly severe childhood epilepsy syndromes (Dravet and Lennox-Gastaut syndromes). Use outside these indications is off-label. The Medicinal Cannabis Scheme does not set a minimum age, but prescribers are expected to follow paediatric guidance from the NZ Formulary and specialist advice. In practice, most New Zealand scripts for under-18s are written by paediatric neurologists for epilepsy, and the product is a high-CBD oil.

The legal route

Medicinal cannabis in New Zealand operates under the Misuse of Drugs Act 1975, and the Medicinal Cannabis Scheme was fully implemented in 2020. Under the scheme, a medical practitioner can prescribe a CBD or THC product that meets GMP standards and has been approved by the Ministry of Health. The legal route is a script from a doctor, then dispensing through a pharmacy. Medsafe, via the Medicinal Cannabis Agency, runs the scheme and maintains a public list of approved items. The NZ Formulary includes cannabis product monographs and gives prescribers guidance on dosing and monitoring. The Misuse of Drugs (Medicinal Cannabis) Regulations 2019 set the quality standards, and the scheme is administered by the Ministry of Health. The key legal fact: medicinal cannabis products are controlled medicines, not “natural health products.”

The patient pathway

  • Step 1, Check whether you are eligible: Medicinal cannabis is not a first-line treatment. In New Zealand, a doctor may prescribe it only when conventional treatments have failed or caused intolerable side effects, and the condition is one where there is some supporting data (chronic pain, cancer-related symptoms, refractory epilepsy, chemotherapy-induced nausea, or multiple sclerosis spasticity). The judgement is clinical, not legal; there is no registry, no list of qualifying conditions, and no “cannabis card” in New Zealand.
  • Step 2, Book a GP or specialist appointment: The pathway starts with a medical practitioner. GPs can prescribe, but many are not confident; if your GP declines, ask for a referral to a pain specialist, palliative care specialist, or a clinic that works with medicinal cannabis. You do not need a referral to see a private cannabis clinic, but you do need a script from a registered medical practitioner.
  • Step 3, Bring your medical history: The practitioner will assess your condition, previous treatments, and any contraindications (unstable heart disease, psychosis history, pregnancy, breastfeeding). They may request records from your usual doctor.
  • Step 4, Get a script, not a recommendation: A script must be written by a medical practitioner authorised to prescribe. It specifies the product, dose, and form. You cannot buy medicinal cannabis over the counter or from a “cannabis clinic” without a script.
  • Step 5, Dispense through a licensed pharmacy: In New Zealand, medicinal cannabis products are dispensed by a licensed pharmacist, not a dispensary or retail outlet. The pharmacist will check for interactions and explain administration.
  • Step 6, Titrate under medical supervision: The dose is individualised, starting low and going slow; the prescriber will guide adjustments based on response and side effects.
  • Step 7, Know your legal boundaries: You cannot legally possess or use raw plant material unless it is a prescribed product dispensed through a pharmacy; growing your own or buying from a “dispensary” is illegal and not covered by the scheme.
  • Step 8, Store securely: Keep products in original packaging, out of reach of children, and ideally in a locked container; the law requires that prescribed controlled drugs be stored safely.

The bottom line first

Under New Zealand’s Medicinal Cannabis Scheme (established under the Misuse of Drugs Act, with the scheme running since 1 April 2020), medicinal cannabis products are prescription medicines. They are regulated by Medsafe through the Medicinal Cannabis Agency. But being legal under a doctor’s order does not mean they are automatically safe in pregnancy, while breastfeeding, or for young people.

For these groups, the consistent position from the New Zealand Ministry of Health and international systematic reviews is: avoid except in rare, specialist-driven situations. There is no established safe dose, no accepted “therapeutic window” for a fetus or infant, and no high-quality studies showing that cannabis-based medicines improve outcomes specific to pregnancy or breastfeeding. The NZ Formulary and the Medicinal Cannabis Scheme do not list pregnancy-related indications. If you are pregnant, breastfeeding, or under 25 and considering medicinal cannabis, the question is not “Is it legal?” but “Is there a safer alternative?” If you are pregnant or breastfeeding, the default answer is: do not start, and if already prescribed, review with your prescriber.

What the law and the regulator say

Under New Zealand’s Medicinal Cannabis Scheme, which began on 1 April 2020, a medical practitioner can prescribe a CBD or THC product that meets GMP standards and is approved by the Ministry of Health (Medsafe, 2020). The scheme does not create a general right to use cannabis. It applies to manufactured pharmaceutical items dispensed through a pharmacy.

The New Zealand Formulary (NZF) is the official prescribing guide. It lists medicinal cannabis items and their funded status. As of the 2024 update, no medicinal cannabis item is funded by Pharmac for general use; patients pay full price unless they qualify under a specific hospital exception. Medsafe’s Medicinal Cannabis Agency (MCA) licences producers and importers, and the Misuse of Drugs Act sets the legal boundary: possession or use outside a script remains an offence.

Pregnancy, breastfeeding and young people: what the official guidance says

For pregnancy and breastfeeding, the NZ Formulary states that cannabis items should be avoided unless the potential benefit clearly outweighs the risk. The Ministry of Health and Healthify advise that the studies are insufficient to recommend medicinal cannabis in pregnancy or while breastfeeding. In practice, a prescriber may consider it only when conventional treatment has failed and the condition is severe. Even then the judgement is made by a specialist, not a general practitioner alone.

For young people (under 18), the NZ Formulary notes that findings are strongest for certain forms of refractory epilepsy (Dravet syndrome, Lennox-Gastaut syndrome). For other indications in children and adolescents the research is limited. Prescribing is off-label, requires specialist oversight, and should only occur after conventional treatments have failed.

How to weigh the risks with your prescriber

When you discuss medicinal cannabis with a doctor, bring a structured set of questions. The checklist below turns the official cautions into a conversation you can have in the consulting room.

  • What is the exact product and its THC:CBD ratio? Ask for the specific brand, concentration, and whether it is a full-spectrum or isolate formulation. In pregnancy and breastfeeding, any THC exposure is the primary concern because it crosses the placenta and enters breast milk.
  • What are the known risks for this group? For pregnancy, the documented concerns include low birth weight and potential neurodevelopmental effects. For breastfeeding, THC accumulates in breast milk and can cause sedation and poor feeding in the infant. For young people, the main worry is the impact on brain development, particularly memory, attention and executive function.
  • Has every safer alternative been tried and documented? The prescriber should be able to list the conventional treatments attempted, their durations, and the reasons they failed or caused harm. If this history is not in your notes, ask for it to be recorded before a cannabis item is considered.
  • What is the monitoring plan? You need a clear schedule for follow-up appointments, dose adjustments, and side-effect tracking. For pregnancy, this includes fetal monitoring. For breastfeeding, it includes watching the infant for sedation, feeding changes and respiratory changes. For young people, it includes school performance, mood and sleep tracking.
  • What is the exit plan? A medicinal cannabis script should not be open-ended. Agree on a review date (for example, four weeks) and the criteria that would trigger stopping or tapering the item. Document those criteria in your notes.

What the studies can and cannot tell us

The systematic reviews cited by the Ministry of Health and the NZ Formulary draw on observational studies, case series and a small number of randomised controlled trials in adults. For pregnancy and breastfeeding, the human data comes mainly from cohort studies of recreational cannabis use. Those studies show associations between heavy THC exposure and adverse outcomes, but they cannot isolate THC from confounders such as tobacco smoking, alcohol use and socioeconomic factors. That does not make the risk disappear; it means the precautionary stance is driven by a known plausible mechanism (endocannabinoid system disruption during development) and an absence of reassuring safety data.

For young people, the strongest trial findings come from high-CBD products for Dravet and Lennox-Gastaut syndromes. Those trials showed a reduction in seizure frequency compared with placebo. Outside those syndromes, the published reports are small, short-term and not placebo-controlled. The NZ Formulary therefore restricts its paediatric recommendations to those epilepsy syndromes and leaves other uses to specialist judgement.

What to do if you are already using cannabis and fall into one of these groups

Do not stop a prescribed item abruptly without talking to your prescriber. A sudden stop can cause withdrawal symptoms and may worsen the condition being treated. Book an appointment specifically to review the script. Bring the questions from the checklist above. If you are using non-prescribed cannabis, be honest with your doctor; the conversation is confidential, and the goal is to find a safer plan, not to judge. Your doctor can help you taper safely and connect you with alternative treatments that have better safety profiles for pregnancy, breastfeeding and young people.