How to Get Started with Medical Cannabis Flower
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For many patients, a prescription will be the first time they’ve seen cannabis flower in person. While the prescribing doctor should go over the basics of how to consume it, it can be daunting to begin vaporising cannabis without detailed guidance. This guide gives a brief overview of weighing, grinding, vaporising, and storing prescribed cannabis flowers.
Equipment for using cannabis flower
Required
Grinder
Dry herb vaporiser
Set of scales
Cleaning materials
Optional, yet helpful
Something to store ground flower, such as a small jar
Tray for preparing medication
Small brush for cleaning grinder/tray
Locked storage box or bag for keeping medication safely out of reach
Scales for weighing cannabis flower
Preparing cannabis flower
Weighing cannabis flower
Your doctor will state the starting and maximum daily dose of prescribed cannabis flower. This means you will need to weigh the dose.
Scales are available with a precision of 0.01g and can be purchased online, or from a vaporiser store. Some patients prefer to grind the cannabis flower and then weigh out the desired amount.
Grinding cannabis flower
It is recommended to break down your cannabis in preparation for use in a vaporiser. Whilst some vaporisers can handle a dense flower it is generally not recommended, as this can lead to insufficient vaporisation. You may need to remove larger stems and extra leaves, which can taste unpleasant when heated, however are not harmful to consume and would not have a large impact on the medical properties.
Grinders come in various forms and are designed to shred, chop, or grind, to break up cannabis flower into a variety of consistencies for use in a vaporiser. Grinders can be purchased online and can be found in some high street shops.
Four-piece grinder
Acrylic grinders are cheapest, known for having sharp teeth, but that can dull over time. More durable are metal grinders, boasting strong and sharp teeth. Requiring just a click of a button, electric grinders are similar to coffee grinders and are easy to operate, however do grind flower quite finely. Card grinders are also available and work in the same fashion as a cheese grater.
Two-piece single chamber grinders most commonly available, usually featuring a lid as well as a grinding compartment, which contains the teeth that grind up cannabis, however it can be difficult to separate the ground up cannabis from the grinder itself. Three-piece grinders include a chamber to catch ground up cannabis and four-piece grinders have an added fine-mesh bottom and an additional chamber for the storage of kief that has separated from the ground up cannabis.
DaVinci MIQRO vaporiser
Vaporising cannabis flower
What is a dry herb vaporiser?
Dry herb vaporisers heat ground cannabis flower to the temperature where terpenes and cannabinoids are released to be inhaled, but do not get so hot as to combust (burn) it. Producing a minimal smell, vaporisers can be used fairly discreetly.
Vaporisers can be handheld/portable or desktop, and powered by electricity, batteries, or external heat sources like a butane lighter or conduction heater.
Nicotine vaporisers, e-cigarettes or vape pens cannot be used to inhale cannabis flower.
Using your vaporiser
Load your weighed and ground cannabis flower into the heating chamber of your vaporiser, following manufacturer instructions. Some vaporisers come with dosing capsules, which can be filled and then put into the heating chamber. Once loaded, turn your vaporiser on and set your chosen temperature.
It is important to set your vaporiser to the right temperature; too low and you may not be activating the crucial compounds found in cannabis; too high and this can degrade terpenes and cannabinoids as well as producing more toxic compounds that may be detrimental to your health. Some patients prefer to start with a lower temperature, gradually increasing to a higher rate.
As you use your cannabis flower you will start to notice a change in the smell and taste, meaning your cannabis may now be ready for changing to a fresh dose. Check for a change in colour; the flower will become browned, losing much of the green colour you started with.
This chart shows the boiling/activation temperature for different cannabinoids.
| Compound | °C |
|---|---|
| THC | 157°C | CBD | 170°C |
| Delta-8-THC | 175°C |
| CBN | 185°C |
| CBG | 200°C |
| CBC | 220°C |
| THCV | 220°C |
Cleaning your vaporiser
Vaporisers need to be cleaned regularly. Vaporised cannabis produces a sticky resin that coats the air pathway of the vaporiser and chamber that stores the herbs. Each vaporiser will have individualised cleaning instructions.
Specialised vaporiser wipes or cotton buds soaked in isopropanol can be used to remove any built-up resin. It is recommended to heat the vaporiser and allow it to cool after cleaning before use, to remove any possible residue.
Avoiding unpleasant side effects
As with any new medication, it is advised that you start use in a safe and comfortable environment. Start with a small dose, inhaling one or two times, waiting 15-30 minutes to assess how you feel. If you are not experiencing adverse effects and have not obtained relief, continue slow inhales. Over time, patients find their individualised dose and number of inhales they need to obtain relief.
If you consume too much or too quickly, side effects such as anxiety, paranoia, drowsiness, nausea or headaches can sometimes occur. These typically subside within 1-2 hours. Side effects should be reported to your clinician or pharmacist, who may be able to find a more suitable medication for your needs. If you need urgent care, call 111/999 and tell them what medication you have taken.
Coughing is a common problem when starting out using a dry herb vaporiser. To minimise coughing, you can start at a lower temperature and inhale small amounts of vapour in a well-ventilated environment. Alternatively you can add a ‘whip’ to your device to cool it further, such as a food grade silicone straw.
Some cannabis flowers can cause more significant side effects than others. You may benefit from a different product with a different amount of THC/ CBD or different terpene profile which you can discuss with your prescribing doctor.
It can take time to adapt to the side effects of medicinal cannabis and this medication isn’t right for everyone, however when effective it can greatly improve a patient’s quality of life.
How to store and handle cannabis flower
Cannabis is a highly controlled medication and should be stored in the container it was prescribed in whenever possible. Only one package of each product should be opened at a time.
If due to dexterity or other accessibility reasons you’re unable to use the prescription packaging, please liaise with your pharmacy to establish whether they have alternative packaging available. Should you be unable to use the prescription packaging, cannabis flower should only be stored in sterilised jars with airtight seals and kept away from light. Do not throw away the original packaging if your medication is transferred to an alternative container. Be mindful that improper storage can introduce mould and microbial contamination.
Identifying problems
As with any medication, there is a very small risk that a cannabis flower product could have issues with an individual batch. It is important to know how it should look so you can identify problems. All prescribed medical cannabis is GMP certified, however because it is a natural plant there can occasionally still be problems during or after processing. While cannabis can have a variety of strong odours it should not smell musty when you open the package. PLEA Advisory Board member Dr Callie Seaman has put together a blog of issues to look out for.
Any quality issues should be reported to the pharmacy, including pictures and batch number/expiration date. Where significant issues arise, medication may be recalled by the pharmacy, in which case ensure medication is stored, photographed and returned in original packaging.
How cannabis flower should look
Cannabis flower with mould present
Reporting contacts for pharmacies:
CBPM Pharmacy | orders@cbpmaccess.co.uk | 0800 1412 055
Dispensary Green | reporting@dispensarygreen.com | 020 8194 6638
IPS Pharmacy | medicalcannabis@ips-pharma.com | 0208 481 9740
All content on the PLEA website is created and published online for informational purposes only. It is not intended to be a substitute for professional medical advice and should not be relied on as health or personal guidance.
Patient Experiences
Thank you to our PLEA Patient Working Group members for sharing their experiences.
