trileptal and marijuana

Compound derived from marijuana interacts with antiepileptic drugs

New research published in Epilepsia, a journal of the International League Against Epilepsy (ILAE), suggests that an investigational neurological treatment derived from cannabis may alter the blood levels of commonly used antiepileptic drugs. It is important for clinicians to consider such drug interactions during treatment of complex conditions.

Cannabidiol (CBD), a compound developed from the cannabis plant, is being studied as a potential anticonvulsant, and it has demonstrated effectiveness in animal models of epilepsy and in humans. An ongoing open label study (Expanded Access Program) conducted by investigators at the University of Alabama at Birmingham is testing the potential of CBD as a therapy for children and adults with difficult to control epilepsy. The study includes 39 adults and 42 children, all of whom receive CBD.

Because all of the participants are also taking other seizure drugs while they are receiving the investigational therapy, investigators checked the blood levels of their other seizure drugs to see if they changed. “With any new potential seizure medication, it is important to know if drug interactions exist and if there are labs that should be monitored while taking a specific medication,” said lead author Tyler Gaston, MD.

Dr. Gaston and her colleagues found that there were significant changes in levels of the drugs clobazam (and its active metabolite N-desmethylclobazam), topiramate, and rufinamide in both adults and children, and zonisamide and eslicarbazepine in adults only. Except for clobazam/desmethylclobazam, however, the drug levels did not change outside of the normally accepted range. In addition, adult participants in the study taking clobazam reported sedation more frequently.

Tests also showed that participants taking valproate and CBD had higher ALT and AST (liver function tests) compared with participants not taking valproate. Very high ALT and AST indicate abnormal liver function, but significant ALT and AST elevation occurred only in a mall number of participants (4 children and 1 adult), and the levels returned to normal after discontinuation of valproate and CBD.

“While the interaction between CBD and clobazam has been established in the literature, there are currently no published human data on CBD’s potential interactions with other seizure medications,” said Dr. Gaston. “However, given the open label and naturalistic follow-up design of this study, our findings will need to be confirmed under controlled conditions.”

The findings emphasize the importance of monitoring blood levels of antiepileptic drugs as well as liver function during treatment with CBD. “A perception exists that since CBD is plant based, that it is natural and safe; and while this may be mostly true, our study shows that CBD, just like other antiepileptic drugs, has interactions with other seizure drugs that patients and providers need to be aware of,” said Dr. Gaston.

New research suggests that an investigational neurological treatment derived from cannabis may alter the blood levels of commonly used antiepileptic drugs.

How Cannabis Interacts With Mental Health Medication

Today, marijuana law is still lingering around in a grey area, despite a growing number of patients using cannabis for medicinal relief. To date, there are still no recorded deaths related to marijuana, yet it might dangerously interact with a patient’s prescribed mental health medication.

Before diving right into the potential interactions of combining cannabis with pharmaceuticals, first we should understand what’s in cannabis. Each variety or strain of marijuana contains hundreds of compounds, many of which are medicinal. The most important and abundant medicinal ingredients in cannabis are compounds called cannabinoids, with THC and CBD being the most abundant constituents. Whether psychoactive or non-psychoactive, marijuana comes in many varieties, so this is why the cause and effect needs to be carefully monitored.


For most patients, marijuana is relatively safe and can make one feel more relaxed, less stressed, and of course, happier. However, its use can also result in a range of adverse mental health effects. Some individuals are more vulnerable than others to experiencing negative effects on high doses of marijuana, especially those with a personal or family history of mental illness. There are some cases where cannabis has the potential to decrease the potency or effectiveness of other drugs. For example, one may feel overly sedated when consuming cannabis with a sedative.

Doctors prescribe medication for different mental issues to bring relief from the unpleasant symptoms that a patient may be experiencing. Continuing marijuana use while taking prescribed medications may cause unpredictable reactions and/or worsen a patient’s condition. It may also make it difficult for one’s prescribing doctor to properly diagnose. Being aware of which pharmaceutical drugs shouldn’t be taken in combination with cannabis will allow for a safer and more enjoyable experience. Below are the most common drugs people combine with marijuana.


Surprisingly, despite years of investigative research between cannabis use and mental disorders, there have been few studies published that closely examine how it interacts with antidepressants. Nonetheless, today, it’s likely that newer antidepressants carry a low to moderate risk for contraindications, while older antidepressants carry a much higher risk. Those suffering from depression are usually prescribed antidepressants belonging to one of four main groups.

  • Allegron
  • Anafranil
  • Tryptanol
  • Imipramine
  • Prothiaden
Selective Serotonin Reuptake Inhibitors (SSRIs):
  • Zoloft
  • Aropax
  • Cipramil
  • Prozac
  • Luvox
Monoamine Oxidase Inhibitors (MAOIs):
  • Aurorix
  • Nardil
Newer antidepressants:
  • Avanza
  • Effexor
  • Edronax

There has been little conducted research on the effects of using marijuana while taking prescribed antidepressant medication, however, there have been reports of numerous contraindications. Symptoms include:

  • Rapid heart rate
  • Dizziness
  • Anxiety
  • Panic
  • Drowsiness
  • Nausea
  • Mental confusion
  • Headache
  • Muscle twitching
  • Gastrointestinal distress

Using marijuana while on antidepressants can be potentially dangerous, as it can intensify any or all of these side effects, making a patient’s condition even worse. This is also very similar with sedatives. Alcohol or drugs like Ativan, Valium, and other antidepressants work to produce a calming effect when interacting with the neurotransmitters in the central nervous system. The problem here is that cannabis can also have a sedative effect at different degrees of intensity, depending on cannabinoid content. Mixing cannabis with antidepressants can result in a major central nervous system depression. It’s been advised that cannabis users exercise caution when using sedative drugs, as the combination can be extremely risky.


Antipsychotic medications work as tranquilisers and are most effective in treating people who have had psychotic episodes, hallucinations, and delusions associated with schizophrenia and other psychotic disorders. Some common antipsychotic medications people use include:

  • Zyprexa
  • Seroquel
  • Abilify
  • Geodon

Cannabidiol has many therapeutic attributes as a safe and non-addictive cannabis compound, however it’s interactions may be problematic in some cases. When consumed, the way cannabidiol interacts with enzyme cytochrome P450 is pivotal; in essence, they deactivate each other. At sufficient doses, this compound consumed along with certain antipsychotics can intensify a drug and may cause increased side effects or potentially serious adverse reactions.

Marijuana alters the metabolism when interacting with drugs broken down by cytochrome P450 enzymes in the liver. These enzymes are found in certain classes of antipsychotics that function to metabolise potentially toxic compounds in the body. Unfortunately, once cannabidiol interacts with these enzymes, it prevents the proper breakdown of the drugs. This is why people with schizophrenia can experience severe depression, which may need to be treated. Users should be watchful of these symptoms:

  • Excessive sedation
  • Slow motor skills
  • Decreased cognitive function
  • Confusion
  • Impaired driving


Using marijuana while taking certain medications can have adverse side effects, which may cause symptoms to become more severe and difficult to manage in the long-term. Remember that medications are prescribed to make people feel better. It has been suggested by research that those who seek counseling can greatly improve their chances of giving up or cutting down their marijuana use while taking medication. If you use marijuana regularly and also take prescribed medications, or know someone who does, the following things may help:

  1. Be honest with your doctor: Before prescribing, make him/her aware of your marijuana use, both how frequent and how much you’re using.
  2. Time matters: Give your medication a chance to take effect, as it can take up to six weeks or more.
  3. Listen to your body: If there are any serious complications experienced when consuming prescription medication and marijuana together, seek help from a healthcare professional to determine what is best for you.


Even if avoiding cannabis for an extended period of time may sound inconceivable to some, it may need to be given up (at least temporarily) if it poses dangerous health risks when combined with another drug. However, cannabis itself is experienced differently by each user. Consequently, adding prescriptions to the equation will more than likely cause unique reactions in people that current research can’t exactly quantify.

Marijuana is known to treat a number of diseases, but despite this, using it with prescribed medications can cause unpredictable interactions.