Will Medical Marijuana Affect my Other Prescription Drugs?

The short and simple answer is “yes!”   Drugs interact with other drugs.  Even foods like grapefruit can react with drugs.  Natural compounds found in medical marijuana can also affect drugs. Because   medical marijuana has been illegal for about 80 years, a lot of time has been wasted.  Studies that could have examined this issue have been very scarce, since it has been out of the loop. On top of this, most orthodox doctors have little or no knowledge and experience in medical marijuana.  That is why it is so important for you to include a Medical Marijuana Doctors Florida physician that has the experience to safely incorporate medical marijuana into your treatment regime. Click on this link to find out more about them:  https://docmj.com/.

What are drug interactions?

A drug interaction is an interaction between a drug and another substance that prevents the drug from performing as expected.  They are of concern, because they can reduce the desired effects or increase the adverse effects of the drugs. Interactions can be either an additive effect or a synergistic effect, where the effect is greater than the sum of the two parts. It can also be a negative effect, such as inhibition.   

Why do medical marijuana products affect prescription drugs?    

  • All compounds, including food, medications, and natural pharmaceuticals such as medical marijuana, once inside the body, have to be broken down. Once they are broken down, they will be able to be utilized and then will exit the body. Medications taken orally are usually sent to the liver first for any needed “taking apart” or “adding to”  to start being metabolized.
  • Medical marijuana is also taken to the liver, for processing by liver enzymes, prior to going through the blood stream to the rest of the body.  In the liver, both the CBD and the THC compounds in it are changed or metabolized by enzymes. Both CBD and THC can inhibit some drugs from getting  metabolized. It is like a slow crawl on the interstate at rush hour traffic.  The processing of the drug in the liver slows down. As the result, the drug level will increase in the blood stream causing adverse effects. [1]  [2] On the other hand, medical marijuana will cause some medications to be metabolized faster. This can cause the level of the drug in the blood stream to be lower than therapeutic.
  • If you are taking full spectrum medical marijuana, some of the terpene compounds in it can also affect other medications. The terpenes can either induce or inhibit other medications. [1]
  • The way medical marijuana is consumed adds another layer to the complexity of drug interactions. It can also be eaten, smoked, vaporized, rubbed on the skin, or absorbed under the tongue. The mode of consumption affects how much of the compounds and how fast they  are delivered to the liver. [2]
  • Just because medical marijuana might affect your medicines DOES NOT mean that you cannot utilize it.  However, it is good reason to make sure that you have a physician with MMJ Doctors in Florida, to safely steer you through the maze of potential adverse effects of your prescription medications. You will need a physician experienced in medical marijuana/cannabis such as http://docmj.com.

Let’s look at some of the drugs that can be affected:

Take out your medication bottles, both prescription and over the counter, while you read this section.  Put them on the table and refer to them. Please note that this is NOT a complete list.

  • Drugs that lower blood pressure- anti-hypertensives: People should be advised to watch for signs of hypotension, or low blood pressure.   On the other hand, some strains of medical marijuana will increase blood pressure in some individuals.
  • Drugs that affect blood sugar levels, such as insulin and oral agents such as Metformin and Glucophage.  It is thought that insulin resistance is decreased by medical marijuana.
  • Drugs that increase risk of bleeding, such as Coumadin, Warfarin, Heparin, Ibuprofen, Naproxen.  Medical marijuana can increase the risk of bleeding with these medications.
  • Pain medications such as opioids.  Often, pain medications can be weaned more efficiently when on medical marijuana. It can decrease pain, as well.   
  • Alcohol.  Medical marijuana can increase the effects of alcohol.
  • Sedatives, such as benzodiazepines- Medical marijuana can increase the drowsiness caused by other drugs. It can have an additive effect to the medication.  Often, sedatives can be weaned very slowly, while incorporating it.  
  • Some antidepressants such as tricyclic antidepressants and SNRIs, such as  amitriptyline, amoxapine, desipramine.  You may have increased drowsiness.
  • Barbituates, such as phenobarbital.
  • Anti-histamines.  Medical marijuana can potentiate the drowsy effect of anti-histamines.

It is recommended that a MMJ Doctors physician assist you, if you are taking any of these medications.  Check here for eligibility:    https://docmj.com/eligibility-survey/

Safety of Medical Cannabis/Marijuana

Marijuana was used safely by most cultures for thousands of years for medicinal purposes.  The past 80 years it was made illegal, not based on science, but secondary to political reasons.  It was replaced by petrochemical based drugs, that cause as many as 2.2 million serious adverse effects per year.  Because many patients are on multi-drug regimes already, it is wise to use medical marijuana with caution. Using a Medical Marijuana Doctors Florida physician is the first step.               

A  study was done of  a systematic review of safety studies of medical cannabinoids published over the past 40 years, to create an evidence base for medical cannabis-related adverse events. The results showed that “ there was no evidence of a higher incidence of serious adverse events following medical cannabis use compared with control (rate ratio [RR] 1.04, 95% CI 0.78–1.39).” This was in spite of the fact that the clients that were in the study had serious illnesses (such as RA, MS, cancer, Parkinson disease, etc.).  The clients were on multiple medications.  However, adding medical cannabis product did not significantly increase adverse events.  [3]

Although medical marijuana is safe,  it is very important to have a knowledgeable MMJ Florida physician safely steer you through the possible adverse effects of your pharmaceutical medications, while taking it.  

Click here to access a physician: http://docmj.com

  1. Austin, C. A., Shephard, E. A., Pike, S. F., Rabin, B. R. & Phillips, I. R. The effect of terpenoid compounds on cytochrome P-450 levels in rat liver. Biochem. Pharmacol. 37, 2223–2229 (1988).
  2. Guengerich, F. P. Cytochrome P450 and Chemical Toxicology. Chem. Res. Toxicol. 21, 70–83 (2008).
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2413308/

CMAJ. 2008 Jun 17; 178(13): 1669–1678.
doi: 10.1503/cmaj.071178
PMCID: PMC2413308
MID: 18559804  Adverse effects of medical cannabinoids: a systematic review       Tongtong Wang, MSc, Jean-Paul Collet, PhD MD, Stan Shapiro, PhD, and Mark A. Ware, MBBS Msc