Guidelines for prescribing medicinal cannabis in New Zealand can support doctors and patients to make better healthcare decisions together.
Medicinal cannabis was only legalised in New Zealand in 2018 and the Medicinal Cannabis Scheme, which is designed to improve patient access to cannabis-based medicines, was introduced in 2020.
Prescribing medicinal cannabis is new territory for New Zealand doctors, but over the coming years, it’s likely to become run-of-the-mill.
The growing demand for medicinal cannabis products, changing attitudes, and the burgeoning medicinal cannabis industry in New Zealand will likely result in more patients seeking advice, guidance, and prescriptions from their doctors.
To support New Zealand doctors with this change, Ora Pharm has teamed up with local and international experts to develop robust prescribing guidelines for medicinal cannabis.
Doctors can use these prescribing guidelines to support clinical decision making and provide patients with evidence-based advice about using medicinal cannabis safely and effectively.
This article is a condensed version of Ora Pharm’s complete prescribing guidelines, which can only be accessed by registered healthcare professionals.
To get full access to Medicinal Cannabis Prescribing Guidelines, including information on specific health conditions and titration protocols sign up to Ora Support, our education and research portal for doctors and healthcare professionals.
Clinical assessment before prescribing medicinal cannabis
As with all prescription medicines, practitioners must exercise their professional judgement in determining if a cannabis product is an appropriate treatment for a patient.
Some patients may have been using cannabis recreationally or medicinally for years and want to pursue legal options. Others may have conducted extensive research of their own and are convinced that medicinal cannabis is right for them. Others may simply be curious about the potential of medicinal cannabis and want advice.
Every patient will have their own story, but all will ultimately want the same things — to improve their health and quality of life.
Once you’ve conducted the standard clinical assessment and diagnosed the patient, we recommend going through the following checklist when considering the suitability of medicinal cannabis.
Mental health history
Any personal and/or family history of mental illness should be considered, particularly schizophrenia. If present, no THC is advised.
High-dose THC medicines should be avoided in under-25s. For children and elderly or frail patients, take care with all cannabis medicines. Age restrictions do not apply to CBD for certain conditions if supervised.
As always, any increased risk should be weighed against potential benefits. In particular, consider cardiovascular, liver and renal disease (avoid cannabis or use with caution); treatments that have been tried and have failed, and their duration; previous cannabis use (recreational or self-medication).
Previous cannabis use may not be a contraindication, but the risk of dependence should be managed. Consider behaviours associated with drug dependence and substance abuse, including nicotine, alcohol or illicit drugs.
Women who are planning to conceive, or are pregnant or breastfeeding, should avoid all use.
Treatment plans for medicinal cannabis patients
Once the suitability of medicinal cannabis has been determined, a treatment plan can be developed together with the patient.
We can’t recommend specific medical cannabis blends or dosages for specific health conditions here, but you can access that information by signing up for Ora Support.
The general guidelines provided here are based on advice gathered from several randomised controlled trials (RCTs), clinical studies and official institutions, as well as clinicians and experts in the medicinal cannabis field, and general practitioners from other countries in which medicinal cannabis prescriptions are legal.
Initial treatment plan
An initial treatment plan should be clearly documented and discussed with the patient and should identify measurable outcomes to monitor, such as effectiveness, side effects and management of other symptoms. Consulting a specialist in the medicinal cannabis field might be appropriate.
Start low, go slow — and stay low
The general principle should be to start low, go slow – and stay low. The optimal dose is the lowest dose necessary to achieve a therapeutic goal with no adverse side effects.
Onset, duration and administration
The onset and duration of a cannabis medicine’s action differ depending on the route of administration. Considerations will need to be made regarding the patient’s lifestyle and responsibilities. You can learn more about that here.
CBD vs THC
A high CBD, low THC product is recommended as a starting point unless this is contraindicated for the patient’s condition. High THC products are more effective for some conditions (for example, pain). It is generally recommended to start THC products in the evening to minimise psychoactive side effects, particularly in the initial 4–6 weeks of therapy.
4-12 week trial
An initial treatment duration of 4–12 weeks is suggested to determine if the medication is effective for the patient’s condition and symptoms. If it is effective, treatment may continue with periodic evaluations.
Require a patient diary
A patient diary will assist your guidance in the titration process. Patients can keep a pen-and-paper daily record of dose, frequency, symptoms and side effects, or use a digital diary such as the new free Ora Pharm App, which you can also use to communicate with patients and adjust their dosage.
If side effects are problematic, a dose reduction of about 25% is recommended. Patients should be advised to seek guidance from their physician if even mild adverse effects (drowsiness, dizziness, dry mouth, disorientation) appear. Severe adverse effects such as tachycardia and psychosis are very rare. Learn more about medicinal cannabis side effects here.
Drug-drug interactions should be considered, particularly interactions with sedative drugs, anti-epileptic drugs, opiates, immunotherapeutic agents or cardiac medications. The pharmacokinetics of most cannabis products are not known. The patient diary should assist with this aspect.
To get full access to Medicinal Cannabis Prescribing Guidelines, including more details about developing a patient treatment plan, sign up to Ora Support, our education and research portal for doctors and healthcare professionals.
Improving safe access to medicinal cannabis
There is good evidence from RCTs that cannabis-based medicines are effective for a growing number of health conditions.
Doctors in New Zealand are tasked with helping to improve patient access to these medicines, through the Medicinal Cannabis Scheme.
By using Ora Pharm’s prescribing guidelines for medicinal cannabis, doctors and healthcare providers can have greater confidence when advising and guiding patients.
Again, if you would like complete access to the medicinal cannabis prescribing guidelines, as well as our research database and other resources for medical practitioners, please sign up to Ora Support today.