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While marijuana is an amazingly safe and forgiving medicine, it is possible to consume too much. Consuming too much THC at one time can leave you feeling quite unpleasant, but the good news is that you cannot overdose on marijuana. If you’re unsure of how much THC to consume in one sitting without feel adverse effects, our physicians here at DocMJ can provide guidance on dosing during an in-person evaluation. You can find out if you pre-qualify for a medical marijuana recommendation by completing our online eligibility survey.
Why can one NOT overdose on marijuana?
- Medical marijuana is not like petrochemical drugs. Regular petrochemical drugs have one or few active ingredient(s). If the active ingredient causes adverse effects, there is not always another active ingredient to counteract it. So, the adverse effect is expressed.
- On the other hand, full spectrum medical marijuana has multiple active ingredients. Not only does it have THC and CBD, it has several hundred other cannabinoids, as well as terpenes. These compounds act together to form an entourage effect. This gives it a balanced effect, as well as an effect larger than all the individual components added together.  It also eliminates the possibility of “overdosing” from it.
- The difference in our response (a bell shaped curve) to medical marijuana versus drugs makes it harder to consume too much. 
We have a different type of response to medical marijuana than to petrochemical drugs
- With most medications, a higher dose will pack a stronger punch. It is not so simple with medical marijuana. Instead of a straight line, medical marijuana has a dose response wave that looks like a bell curve. In other words, if you take too large an amount, it can decrease the desired effect you are taking it for. Even more weird, if you go to extreme high dosages, you may have completely different positive effects, such as killing cancer cells by programmed cell death (apoptosis).
- Although we normally state that medical marijuana has a biphasic effect. It can also be a triphasic or multiphasic effect. What is the meaning of these terms?
- Biphasic means that a person starts with a certain dosage of medical marijuana. When they consume a higher amount, the response may be better. If the person keeps on taking progressively higher amounts, eventually the response is going to decrease. It forms a bell shaped curve, going down. The downward curve means less effect. The optimal dose is in the peak of that curve. 
- Triphasic or multiphasic is because your response can change again as you increase the amount of medical marijuana. Every time you change directions, it becomes a new phase. It is when you really crank up the dose, that the benefit may return. However, what the benefit is, may change with the much higher dose. For example, instead of alleviating nausea and anorexia (lack of appetite) as it does with low to moderately high dosages, an ultra high dosage may cause apoptosis (programmed cell death) of cancer cells.  
Possible adverse effects with higher doses of medical marijuana
- Besides differences in effects, you may have adverse effects with higher dosages. You may note that these adverse effects are related to the THC component of medical marijuana. CBD has no known adverse effects at any dose. By changing the ratio from 1:1 CBD:THC, up to 4:1 or 8:1 CBD:THC, then usually the larger CBD component will override the adverse effects of THC.  
- So, what could be those effects of too much medical marijuana? The adverse effects are similar to what medical cannabis can actually relieve at appropriate dosages. They are: nausea, vomiting, diarrhea, sweating, tremors, panic attacks, spasms, disturbed sleep, and paranoia.  
- Rarely, people may have hallucinations and acute psychosis. In these cases, it is usually with people who already have psychological disturbances. If you have psychological issues, use medical marijuana with caution. Some people might need to have a much higher CBD:THC ratio than usual. 
- You can see that these possible adverse effects with medical marijuana are relatively mild compared to those of petrochemical pharmaceutical drugs, that cause 2.2+ million serious adverse effects a year.
More problematic than adverse effects of medical marijuana, is the possibility of drug interactions with medical marijuana
- A drug interaction may occur between your medical marijuana and the petrochemical drug. It causes the drug to not perform as expected. It can cause an additive effect, synergistic effect, or a negative effect. This is another reason for the importance of having a physician who is trained and experienced with medical marijuana, such as our Florida Medical Marijuana Doctors here at DocMJ.
- Medical marijuana is processed in the liver, just as are the majority of drugs. Medical marijuana uses the same cytochrome P450 enzyme system as most drugs. Because of this, not only are the drugs competing with each other, but medical marijuana is also competing with the drugs for processing and utilization. 
How can you keep from having adverse effects with medical marijuana?
Unlike most medications, with medical marijuana, your recommendation is not based on body weight, age, and medical condition. One person may be able to consume, with good effect, only several milligrams per day of cannabinoids. Another person may need several hundred milligrams per day to get the same effect. 
There are a number of factors that may affect what dosage you need for your medical marijuana. They are related to the receptors and enzymes you have for cannabinoids, your genotype, your phenotype, liver function, and etc. 
- Start low and go slow, finding the lowest amount of medical marijuana, that works for you. By consuming the lowest effective dose, you are decreasing the possibility of adverse effects.
- However, the purpose you are taking medical marijuana for, may alter how much you need to take. For example, those trying to kill cancer cells or if they have other severe chronic problems may need several thousand milligrams per day of cannabinoids to have the desired effect (efficacy). Since THC is normally what triggers the adverse effects, if you do have adverse effects, try a strain with a higher amount of CBD and a smaller amount of THC.
So, although you cannot overdose on medical marijuana, we have learned that different dosages may give different results, as well as cause adverse effects. Taking the smallest effective dosage is paramount to not only preventing adverse effects, but also drug interactions. Tweaking downwards the amount of THC or adding terpenes may help prevent adverse effects, which usually occur with higher dosages.
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