Medical cannabis flower is the most commonly prescribed cannabis-based medication here in the UK. But unlike most treatment options, both traditional and alternative, it is not delivered to patients in a fully 'ready-to-administer' form.
It’s up to the patient to grind their prescribed flower before placing it into their vaporiser. Over time (and with frequent use), medical cannabis grinders can become clogged, making the task a little more difficult and, sometimes, less effective.
So, what is the best way to clean a medical cannabis grinder?
Key takeaways
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Maintaining clean accessories (such as grinders and vaporisers) is important. Apart from making the process of grinding your medical cannabis flower easier and more effective, there are other important reasons why you should regularly clean your grinder. These include:
Preventing bacteria or mould issues: Medical cannabis flower is a fully organic product. Even though it is grown in strictly regulated conditions and tested for any contaminants, the fact that the organic material then builds up in your grinder makes it a potential breeding ground for bacteria or mould. By regularly cleaning your grinder, you can reduce this risk.
Improving taste and potency: As mentioned before, medical cannabis flower is covered in sticky trichomes, which harbour much of the plant's cannabinoids and terpenes. Over time, these trichomes can become clogged in your grinder, which can then mix with new batches of ground flower and potentially change the potency and taste of your medication.
Maintaining the longevity of your grinder: A clean grinder is a well-functioning one. By regularly cleaning out any build-up, you can ensure that your grinder will last longer and continue to work effectively.
A quick Google search will show a bunch of different methods for cleaning cannabis grinders, but when it comes to medical cannabis, it's best to stick to simple and safe methods. Here are the materials you will need:
Isopropyl alcohol
A clean toothbrush
A Zip-Lock bag (or a plastic container)
Gloves
Cleaning cloth
The inherent antibacterial properties of isopropyl alcohol make it the best option for medical cannabis patients. It’s easy to get hold of, quickly dissolves sticky build-up and evaporates to leave you with a clean grinder.
Disassemble the grinder: Unscrew the grinder into its individual parts, and use the toothbrush to remove any loose flower still clinging to the parts.
Place the grinder in a Zip-Lock bag: This will make it easier to contain and clean with the isopropyl alcohol.
Add the alcohol: Pour just enough isopropyl alcohol into the bag to cover all parts of the grinder.
Seal the bag and shake: Seal the bag and gently shake, making sure the alcohol is covering all parts of the grinder.
Soak for 30 minutes: Leave the grinder in the bag to soak for about 30 minutes. This will give the alcohol enough time to dissolve any build-up.
Scrub: After 30 minutes, remove the grinder from the bag and use the toothbrush to scrub away anything remaining.
Rinse with warm water: Rinse all grinder parts thoroughly to ensure no alcohol residue remains.
Dry and reassemble: Using a clean cloth, dry all parts of the grinder before screwing it back together.
Isopropyl alcohol is flammable so always make sure you use it in a well ventilated space, keep away from flames, wear gloves, and let every part dry fully before using again.
Using isopropyl alcohol for cleaning medical cannabis accessories is recommended, but there are other methods without alcohol too, such as boiling and using warm soapy water. Which method works depends on what your grinder is made of.
Metal grinders can also be cleaned using warm, soapy water and a soft brush, or are safe for boiling.
To boil your grinder:
Disassemble the grinder (removing any rubber or plastic parts)
Submerge in a pot of boiling water
Simmer for 10 to 15 minutes to loosen resin
Remove carefully from the water with tongs (the pieces will be hot)
Scrub the teeth and crevices with a soft brush
Rinse with warm water
Allow to dry fully to prevent rust
Never boil a plastic grinder as the hot water can warp and damage parts. Instead, use warm soapy water and soft brush to clean the parts, rinse off and allow to dry fully.
Grinders made of acrylic, wood, or with paint or lacquer should also not be boiled or cleaned with isopropyl alcohol. Clean instead with warm (not hot) soapy water.
How often you clean your herb grinder depends on how frequently you use it, but there are some tell-tale signs that it’s time.
You should clean your grinder if:
The lid is stiff (difficult to turn)
The teeth are sticking together
The mesh screen becomes clogged
Generally speaking, grinders should be cleaned once a month for regular or moderate patients, with more frequent cleaning for more frequent use.
We heavily suggest that patients only ever use a metal grinder.
Both plastic and wooden grinders are more susceptible to bacteria or mould growth and are harder to clean thoroughly. The grinding action can also result in microplastics or wood particles mixing with your medication.
Metal grinders are just a much better option when it comes to cleanliness and effectiveness. They can easily be cleaned with isopropyl alcohol and are much more durable. We have a fantastic option available for purchase through our Patient Shop.
A build-up of resin is what typically makes grinders stick or become stiff, so removing it is an important part of the cleaning process.
Isopropyl alcohol is typically recommended as it dissolves sticky resin and makes it easier to scrub and rinse off.
Warm soapy water can be used to remove resin from plastic or acrylic grinders by soaking and scrubbing with a soft brush. Resin build-up in metal grinders may also be removed by scrubbing after boiling.
Cleaning the mesh screen of your grinder should be done carefully to prevent any damage, and it is recommended you gently brush the mesh with a soft-bristled brush (such as a toothbrush) after each use to prevent build-up.
When cleaning, soak the part of the grinder containing the mesh screen in the isopropyl alcohol, soapy water or boiling water (depending on your grinder’s materials), and gently brush the mesh with a soft brush to remove build-up, and rinse before allowing to dry.
It depends what your grinder is made of. Metal grinders are safe for boiling.
Grinders made of wood, acrylic, plastic, or with any paint or lacquer should not be boiled as the hot water can cause warping of parts.
To find out if you are eligible for medical cannabis treatment in the UK, check out our fast and free medical cannabis eligibility checker.
And check out the rest of our New Patient blog series, full of useful information and tips for anyone beginning their medical cannabis treatment journey. We also have a dedicated FAQ section, medical cannabis glossary, education hub, and blog.
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