Cannabis Side-Effects

Although marijuana is known these days to offer a wide range of benefits for sufferers of numerous medical conditions, there are some cannabis side effects which are part and parcel of using the drug. While most of these are quite mild and are short-lived, there are some longer term problems which may become apparent after using weed. While most people, even those who have never touched the herb, know about “the munchies”, there are several other side-effects which are less well known.

What Are The Side Effects Of Cannabis?

Here are nine of the most common cannabis side effects which users should be aware of if they currently use, or are planning to use the drug.


Most people who are cannabis users will already know about cottonmouth – an uncomfortable dryness in the mouth which is caused by reduced saliva production. Around 80% of users experience this problem, although it is more frequently seen in recreational users who have a higher level of consumption. There are several ways in which this problem can be solved – not least by having a glass of water to hand while indulging in weed. However, it's also possible to stimulate the salivary glands by chewing gum or by eating some food (although probably not marijuana edibles!)


Quite a lot of users report that they feel dizzy when they've been smoking weed, especially when standing up. More than half of users are affected by this problem, especially if they are using a stronger strain. The dizziness may well be caused by a drop in blood pressure caused by smoking cannabis, however the most frequent users often become tolerant to the short term effects of weed, and dizziness often becomes less of a problem over time.

The Munchies

The best known cannabis side effect of all, the Munchies refers to the sudden hunger which usually occurs right after smoking. Experts still aren't sure why this effect takes place, but it's believed that the weed activates pathways inside the brain that stimulate appetite. Although some people think that this could be a negative side effect (especially those who have put on weight from raiding their fridge after a session), in fact it is considered to be a benefit to those to are suffering from appetite loss due to a medical problem or chemotherapy treatment.

Memory Problems

There have been a number of studies which have shown that regular users of weed have short-term memory issues, and some other studies have even shown that cannabinoids are capable of impairing all memory stages including long term memory. This is shown to be a more significant problem for young users, with memory impairment being much worse in adolescent weed users, and the possibility of the impact on the memory being permanent.

Lack of Motivation

There's a reason why the classic image of the stoner is of someone who lies around on the couch and can't be bothered to get up. Many critics of the drug are opposed to its use because of the idea that weed causes users to lose all motivation to work and study, however this stereotype is largely exaggerated. Nevertheless, there is some truth to the cliché, with around half of users having reported a loss of motivation after using the drug. This is thought to be because long term users have a lower level of dopamine in the brain, and this chemical is responsible directly for their motivation.


While weed has been shown to be an effective treatment in combating mild to moderate depression, in a few cases, it is possible that it works in the opposite way. The younger the user, the more likely they are to develop depression according to a study which was published in the British Medical Journal in 2002.

Anxiety and Paranoia

Again, weed has been shown to have positive effects on patients who suffer from anxiety, especially those who have PTSD, however this is only effective when taken in lower dosages. If large amounts are taken frequently, paranoia is a common mental side effect. In fact, rather than being caused directly by THC, paranoia is believed to be a byproduct of the other side effects of cannabis, like depression, and also the feeling that the user has of having had an odd experience. Patients who already have panic anxiety may have an increase in their symptoms when they smoke week, although the CBD compound in cannabis has been shown to reduce anxiety in affected individuals.


In general, cannabis isn't thought to be addictive, although, since it is a drug there is always a risk of addiction associated with its use in just the same way as there is a risk of becoming addicted to alcohol or caffeine. When someone stop taking weed, their cannabinoid receptors have to readjust to their normal levels, and this can lead to both physical and psychological symptoms of withdrawal. These symptoms are relatively mild however, and include difficulty in sleeping, reduced appetite and increased irritability.

Respiratory Problems

For those who smoke weed, their marijuana use may have a detrimental effect on their respiratory system. In the same way that smoking regular tobacco cigarettes can cause breathing problems, wheezing and coughing, smoking cannabis can cause similar symptoms. For this reason, many experts suggest that if someone is going to use weed, either recreationally or for the relief of a medical problem, they should avoid smoking it and switch to either edibles or vaping instead. Respiratory problems are no longer a factor without the combustion of smoking.

Although there are some side effects of using cannabis, the majority of them are quite mild and generally pretty short lived. In fact, in general weed seems to do a lot more good than harm as long as it is taken in low to moderate amounts, and as experts in the medical field find out more about its many benefits, especially in terms of treating a host of medical conditions, it appears that its use will become a lot more mainstream.