Does cannabis interact with antidepressants or lithium?
Cannabis and antidepressants
Cannabis or marijuana can interact with tricyclic antidepressants (TCAs), such as amitriptyline, imipramine and dothiepin.
Both cannabis and TCAs can cause an abnormally fast heartbeat (tachycardia) and high blood pressure (hypertension). There’s also a risk of other side effects, such as confusion, restlessness, mood swings and hallucinations.
There’s a risk that using cannabis while you’re on any of these medicines could lead to problems such as tachycardia, even if you don’t already have a heart condition.
Little research has been done into the interaction of cannabis with other types of antidepressants, such as SSRIs.
Cannabis and lithium
Lithium is used to treat bipolar disorder, a condition where people can switch between depression and extreme excitement and agitation (mania).
There’s little evidence to suggest that people who use cannabis should normally not take lithium, but this hasn’t been properly researched.
Side effects of cannabis
It’s not clear how often cannabis itself can cause anxiety or depression, but research suggests this can happen.
It’s therefore recommended that if you’re anxious or depressed and you use cannabis regularly, you should try giving up and see if that helps.
Tachycardia, dizziness, anxiety, drowsiness, nausea and vomiting, difficulty sleeping and confusion are all possible side effects of cannabis.
These side effects can also be caused by certain antidepressants, so using cannabis at the same time can make them worse.
If you have any concerns about the medicines you’re taking, talk to your GP or pharmacist.
You can also phone NHS 111 or Talk to Frank, a friendly confidential drugs helpline, on 0300 123 6600.
- Antidepressant drugs
- Can I drink alcohol if I’m taking antidepressants?
- Medicines information
Page last reviewed: 27 March 2018
Next review due: 27 March 2021
Cannabis or marijuana is usually smoked and typically mixed with tobacco. It can interact with certain types of antidepressants, such as tricyclic antidepressants (TCAs), which share similar side effects.
We Asked Experts What Really Happens When You Mix Weed with Anti-Anxiety Meds
For my first year in college, weed was an old reliable for me. It was a way for me to cope with stress about grades and life in general.
But on April 26 of 2016, that all changed for me. That day, I finished my first year of university. My best friend and I bought some Headband from a guy I knew on residence. We smoked up; I had to finish his joint and that was when I had one of the worst trips of my life.
It sounds weird to say that about weed, that I had such a traumatic experience that I became afraid of something herbal and natural. I don’t know if the buds I got from my guy were laced with something (maybe smoking 1.5 grams in one sitting isn’t a good idea?) but all I remember is hallucinating. I remember seeing what looked like ghosts walk around my residence building; faint grey shadows milling about. I began feeling anxious; there was something bad was going to happen, I just didn’t know what. It was like I was trapped on one of those nauseating, forever-spinning teacup rides in Disneyland and I just couldn’t get off.
I eventually slept it off but the days following were ones that changed my life. Since the end of April till today and likely for the foreseeable future, I’ve been strapped onto the crazy roller coaster that is OCD. Intrusive thoughts, self-hatred, self-harm, never ending guilt, that’s all just the tip of the iceberg. I’ve been struggling but after much trial and error, I finally found a doctor and an anti-anxiety and anti-OCD med to help me cope.
So when a new friend handed me a pipe recently, I was apprehensive about smoking up. I was worried about my OCD getting worse and also extremely concerned of how my medication, Celexa, would interact with THC and CBD. I couldn’t afford to backslide. But I can’t lie, the temptation to take a hit was there.
For anyone else in the same boat, who takes daily medication for anti-anxiety or OCD for that matter, I wanted to look at if it’s possible for us to get the best of both worlds. As in, can we smoke up while medicated?
Selective serotonin reuptake inhibitors, or as they’re commonly known, SSRIs, are a common method of long-term treatment for many mental health issues like Generalized Anxiety Disorder and OCD. SSRIs work to increase serotonin levels in the brain.
On the other end of the spectrum, when smoking a joint, the THC (tetrahydrocannabinols) enters your bloodstream. Consumption of pot also can increase the levels of serotonin in the brain.
This all begs the question, if an SSRI and marijuana both increase levels of serotonin in the body, is this potentially dangerous? How do pot and anti-anxiety meds interact with one another?
VICE spoke to Dr. Ian Mitchell, an emergency physician at Royal Inland Hospital in Kamloops, British Columbia to get a medical perspective on this issue. Dr. Mitchell also is a Clinical Associate Professor at the UBC Department of Emergency Medicine and also works at the Medical Cannabis Resource Centre.
According to Dr. Mitchell, “there’s no known effect or interaction with those medications. We know that THC itself can bring on anxiety and paranoia. Especially in higher amounts. The cannabidiols, which is another cannabinoid, can upset that and can actually be used as an anti-anxiety treatment on its own.”
As for the medical perspective on what can occur physiologically within the body, Dr. Mitchell says, “I think that is very dependent on the person. So, it absolutely can worsen symptoms if it has THC in there. I think you also have to look at what people are currently taking as anxiety medications. When you talk about benzodiazepines for example, they are very addictive. So some people may find that marijuana can be a useful substitute and I would say that that’s not a bad trade if it helps them. But, there are certainly people out there that do have anxiety provoked from marijuana and they should avoid using it. It’s probably as simple as that.”
I was also curious if Mitchell had ever treated someone in hospital who claimed to have a bad reaction to weed while on anti-anxiety medication.
“I can’t say I’ve seen that very much. We see so few emergency presentations for marijuana. Occasionally, yeah we do see people who have smoked too much or eaten too much. Edibles are more likely where people come to the emergency because when they take edibles, they’re often taking a much higher dose and they are not prepared for it. That can cause anxiety issues,” Dr. Mitchell says.
I also spoke to Craig Jones, executive director of NORML Canada, a non-profit group lobbying for the decriminalization of marijuana, about the cocktail of marijuana, anxiety and anti-anxiety meds. He began by telling me that there are three rules of thumb to go off of here, “First, we are still in the early days of research with marijuana and anxiety. Ten years down the road from now, we will know more. I cannot predict those findings at the moment. Second, evidence suggests that people with family histories or pre-existing mood disorders like anxiety and depression should avoid all psychotropics. Third, notwithstanding the second point, many people with anxiety come into contact with harsher chemicals. On a scale that has methamphetamine, heroin and cocaine, marijuana is on the less harmful end of the spectrum. Still, refer back to the second point.”
Jones was critical of the relationship between marijuana and anxiety. “It can certainly trigger anxiety or OCD. It’s also dose-related. Two lungfuls might push you over the edge into full-blown panic attacks. The combination of pharmaceuticals and marijuana is a blackhole. We don’t know the effects. We have to be careful. The combination can be multiplicative rather than additive,” he says.
“To be honest, not a great deal of research has been done on this and I’ll tell you why. It’s very difficult to do randomized control tests because the experience of a cannabis high is a learned experience,” he added in reference to the lack of studies on the subject.
Ultimately, there appears to be no concrete verdict here. Not enough research has been done to definitively answer how marijuana and SSRIs interact. Weed itself is experienced so differently by each user that adding medication to the equation will yield a reaction that current research can’t quantify.
So, all we can really leave you with today is: user discretion is advised.
Is the combo a black hole?