Why Do Certain Drugs Cause Bruxism?

Many drugs increase extracellular glutamate. This is your body's primary excitatory neurotransmitter. Most people are also deficient in magnesium. There are many reasons for this, but I will leave that for another discussion.

Magnesium is your body's main defense against excess calcium transmission into cells due to increased glutamate levels. Due to its charge, magnesium is pulled into the ion channels that are controlled by the NMDA receptors. With low brain magnesium levels, and high extracellular glutamate due to stimulant use, the body is less capable of preventing the influx of calcium in too high a concentration into the neurons. When this happens, it is called excitotoxicity. This can manifest itself in many ways. One of them is bruxism.

The best way to combat this is with a highly bioavailable form of magnesium. Magnesium glycinate is good because it is inexpensive, provides a high amount of elemental magnesium due to the low molar mass of glycine, and provides active transport across your body's lipid bilayers. Memantine is a drug that can help even more, as it binds to an open channel binding site of the NMDAR and closes the ion channel before it can let too much calcium influx.