Does cannabis/THC interact with other drugs used for the treatment of diseases?

[Medical Marijuana]

This is just a general view, and not a scholarly one.

Answers:

* Leo Hollister
Although medical marijuana is not officially approved, marijuana has been tried empirically for treating a variety of medical disorders, such as nausea and vomiting associated with cancer chemotherapy, weight loss associated with AIDS, and spasticity from neurological diseases. In each instance, other drugs are also present. So far, no adverse interactions from such use have been reported. However, this might not reflect the true frequency. Unless one looks for something, one is not likely to find it. (...) The published literature, at least in regard to studies with humans, has been rather silent. Usually this silence indicates that no meaningful interactions have been observed in the real life use of marijuana as compared with experimental studies. (...) One of the most reasonable therapeutic uses of marijuana and THC has been to ameliorate the nausea and vomiting associated with cancer chemotherapy. Thus, cannabinoids will be used simultaneously with many highly toxic cancer drugs. (…) In none of the reports of use of THC or marihuana in patients simultaneously undergoing cancer chemotherapy has there been any mention of increased toxicity of anticancer drugs. Nonetheless, the absence of such reports may signify that no attempt was made to look for them. This avenue of research should be encouraged. A somewhat similar situation applies to the therapeutic use of orally administered THC in treating the weight loss associated with AIDS. (…) THC or marihuana has been used for treating spasticity associated with neurological disorders, such as multiple sclerosis and spinal cord injury. Since THC may be added to therapies with muscle relaxants, it would be of some interest to know whether such combined uses might be harmful. In one animal study in which THC was given with muscle relaxants, it was found to increase the desired effect of the latter drugs. In this case, the interaction might be advantageous.
(Please note: This text has been taken from a scientific article. Some sentences have been changed to improve understandability.)"
Modified according to: Hollister LE. Interactions of marihuana and D9-THC with other drugs. In: Nahas G, Sutin KM, Harvey DJ, Agurell S, eds. Marihuana and medicine. Totowa, NJ: Humana Press, 1999, pp. 273-277.


* Franjo Grotenhermen
Cannabis and dronabinol (THC) have been used in combination with a multitude of medications without significant deleterious drug interactions. Clinical studies in the beginning of the 20th century often demonstrated mutual enhancement of therapeutic effects of cannabis preparations and other drugs. In modern therapeutic concepts a combination of cannabis/THC with other medications could also be of benefit for many indications. Cannabis has been used illegally by individuals suffering from many diseases concomitantly with numerous prescription medicines. No unwanted side effects of clinical relevance have been observed to date. (…) Other medicines may enhance or attenuate certain actions of cannabis/THC or certain actions of these medicines may be enhanced or attenuated by cannabis/THC. Moreover, it is possible that certain effects are enhanced and others reduced, as is the case with phenothiazines applied against side effects of cancer chemotherapy (see below). Of greatest clinical relevance is reinforcement of the sedating effect of other psychotropic substances (alcohol, benzodiazepines), and the interaction with substances that act on the heart (amphetamines, adrenaline, atropine, beta-blockers, diuretics, tricyclic antidepressants, etc.). (…)
· Anti-cholinergics: Atropine and scopolamine may increase the acceleration of heart frequency by THC.
· Anti-cholinesterases: Physostigmine antagonizes the psychotropic effects and the acceleration of heart frequency produced by THC. (…) · Anti-depressants (selective serotonin reuptake inhibitors): THC may increase the effect of fluoxetine.
· Anti-depressants (tricyclics): Frequency of the heart, blood pressure lowering and sedating effects of amitriptyline may be enhanced.
· Benzodiazepines: Respiratory depression and depression of the brain function may be increased. The antiepiletic action may be enhanced.
· Beta-blockers: They reduce increase of heart frequency associated with THC.
· Glaucoma: Several drugs that decrease intraocular pressure and cannabinoids may act additively.
· Neuroleptics: THC may antagonize the antipsychotic actions of neuroleptics. It may improve their therapeutic effects in motor disorders.
· Non steroidal antiinflammatory drugs (NSAID): Indomethacin, acetylsalicylic acid (aspirin), and other NSAIDs antagonize THC effects. Indomethacin significantly reduced subjective "high" and acceleration of heart frequency.
· Opiates: Enhancement of sedation and pain reduction.
· Phenothiazines: Prochlorperazine and other phenothiazines attenuate the psychotropic effects of THC and increase its antiemetic effects.
· Sympathomimetics: Amphetamines and other sympathomimetics enhance the acceleration of heart frequency and the increase of blood pressure.
· Theophylline: The metabolism of theophylline is accelerated by THC. Thus, higher doses of theophylline might be necessary.
(Please note: This text has been taken from a scientific article. Some sentences have been changed to improve understandability.)
Grotenhermen F. Practical hints. In: Grotenhermen F, Russo E, eds. Cannabis and cannabinoids. Pharmacology, toxicology, and therapeutic potential. Haworth Press, Binghamton/New York 2001, in press.

[Johnny]

You always manage to post threads answering questions I've been wondering, *****.

I've been on two benzodiazepines to treat my social anxiety disorder: Ativan (lorazepam) and generic clonazepam, and I find that when used in combination with cannabis, the relief of my symptoms is far greater that just the medications alone. So, needless to say, I usually use them in combination.

I've also been on generic fluoxetine (more commonly known by the brand name Prozac) for quite awhile, but I've never noticed any interactions between that and marijuana.

Thanks for another informative thread, *****.

-jps

[bill704]

I saw a psychiatrist about a week ago who told me she refuses to help me because I told her I would not quit marijuana if she directed me to. She went on to say any drug she prescribes me (I suffer major depression, perhaps ADD) the marijuana would counteract. She added some reefer madness in there by saying the majority of homeless people smoke pot.

This of course I found to be very unprofessional. What significant research is out there describing the effects of anti-depressants and marijuana? As far as I know, there's none because current drug laws prohibit such testing.

I have suffered depression all of my life, yet have only been smoking marijuana for less than 2 years now. Marijuana use has not changed the way I feel, when it comes to my depression. I do not claim to use marijuana for anything other than recreational use, however, it is quite nice to slow down my thoughts and let me sort shit out.

What say you?

[Johnny]

Originally Posted by shthd843

I saw a psychiatrist about a week ago who told me she refuses to help me because I told her I would not quit marijuana if she directed me to. She went on to say any drug she prescribes me (I suffer major depression, perhaps ADD) the marijuana would counteract. She added some reefer madness in there by saying the majority of homeless people smoke pot.

This of course I found to be very unprofessional. What significant research is out there describing the effects of anti-depressants and marijuana? As far as I know, there's none because current drug laws prohibit such testing.

I have suffered depression all of my life, yet have only been smoking marijuana for less than 2 years now. Marijuana use has not changed the way I feel, when it comes to my depression. I do not claim to use marijuana for anything other than recreational use, however, it is quite nice to slow down my thoughts and let me sort shit out.

What say you?

You should try to find a new psychiatrist. The one you went to sounds like a bitch. I've had to try quite a few different anti-depressants before my psychiatrist found one that worked, including Effexor, Wellbutrin, Trazodone, and Prozac, and I never noticed any interaction with marijuana with any of them. The only interactions that have occured with my medications and marijuana are with benzodiazepines like lorazepam and clonazepam, which is actually quite beneficial. My psychiatrist was always cool with my marijuana use and never did anything to try to stop me. She even helped me out and was very supportive when I got arrested and had to go through a big ordeal with the police.

I agree with you finding it unprofessional, as that's exactly how I would have felt in that situation.

Good luck!

-jps

[Boss]

I would refuse to go to a doctor that was not educated.

[Midwestsmoker]

I have Bipolar Disorder and I've tried a few of those anti-depressants and so far the best medicine I've ever tried is MJ. Marijuana is the only thing that has truly helped me. Some of the side affects of those medicines are worse than the problem itself.

[bill704]

Originally Posted by Boss

I would refuse to go to a doctor that was not educated.

I generally don't judge people based on their beliefs, but conservative shrinks have really started to get to me...

Unfortunately, that's all I seem to find around here