Recently, we have been hearing renewed calls for decriminalization of certain illicit drugs and an old debate of whether all drugs should be legal or not continues. Whether your beliefs align with either side of this argument, the fact is that a large number of people in Australia do experiment with illicit drugs at some point in their lives (about 40 percent of Australians over the age of 14 have tried cannabis) and some go on to develop a dependency. Whether you are one of the users or a family member or friend of a user, it is worth getting informed about the effects and side-effects of the commonly used drugs. Cannabis is the most commonly used drug in Australia, so in this blog we are highlighting how prolonged cannabis use affects oral health.

The psychoactive component of cannabis (THC) is usually absorbed through the lungs, then the blood and within seconds, it reaches the brain. There are many ways in which THC affects the body, but when it comes to the mouth, the most powerful effect of THC is that it causes a dry mouth.  Dry mouth is a serious risk factor for tooth decay, as saliva which would typically protect the teeth from bacteria shuts down. Cannabis users also become hungry (“get the munchies”) quite quickly after smoking and often have a preference for high sugar snacks. Together with a dry mouth, these sugary snacks create a perfect environment for tooth decay. It comes as no surprise then that cannabis smokers generally have more decayed, missing or filled teeth than non-users.

Dry mouth and highly acidic, sugary drinks, such as energy drinks and soft drinks, increase the risk of teeth erosion. 

Cannabis use also increases risks of developing oral cancer. This is mostly because cannabis is smoked in a hand rolled cigarette form, usually containing the same carcinogenic substances as a tobacco cigarette (except nicotine) and without a filter. Some users also combine cannabis and tobacco. Any changes of the soft tissues in the mouth (cheeks, tongue, lips, gums, palate, throat), such as white patches or webs, swellings, ulcers and areas of redness need to be taken seriously when it comes to regular cannabis users. These changes may be a sign of cancer of the mouth and need to be detected early. They are often difficult to see in the mirror and only a dentist can detect them.

Long term use of cannabis lowers immunity (immunosupression), so users often suffer from gum disease and fungal overgrowth (which may show as white build up or redness and soreness of the tongue and palate).

It is difficult to separate how cannabis use affects oral health from its effect on people’s overall health and most importantly, their mental health. People who are drug dependent usually have various other habits which may affect their oral health: they may not look after their oral hygiene, they may have a diet which promotes tooth-decay and they are not likely to regularly see their dentist or hygienist for preventative care.

Users must talk to their dentist openly about their use of drugs (not only cannabis), as illicit drugs (as well as prescription drugs) can react with some anaesthetics commonly used in dentistry to cause health complications. If they are aware of the patient’s drug use, the dentist can also keep an eye on the various potential risk areas in the mouth (teeth, gums, soft tissues), which may be affected by the drug use.  They can devise a specific care plan, which may help the user protect their teeth and gums.

If you or someone you know are using drugs regularly and may be drug dependent, you may wish to speak to your GP or visit the Australian National Drugs Campaign website (http://www.drugs.health.gov.au) which contains a number of resources to help you on your way to beating your addiction.