Marijuana, or cannabis, is according to the UN, the most consumed drug in the world. What are the effects of cannabis while diving? It is sometimes used in medicine to relieve patients from some strong disease such as end-stage cancers, Parkinson’s disease, AIDS or multiple sclerosis. In recent years, the legislation of this substance has evolved rapidly, suggesting that the number of its consumers will increase further. But what are the risks of smoking cannabis before a dive?

The Mental and Physical Effects of Cannabis in the Diver
According to Dr. Tom Neuman, a specialist in underwater medicine, cannabis will alter certain motor and cognitive abilities. Divers who consume them before diving would therefore take a risk. For Professor Paul Auerbarch of the Stanford Medical School, the use of marijuana can lead to acute and chronic effects in divers: altered mental status, judgment, and physical reflexes. Because of these potentially harmful effects, he therefore advocates prohibiting this drug among divers.
Until now, it has not been possible to test the effects of taking marijuana on divers in real situations, only laboratory tests have taken place. However, according to Dr. Neuman, it is complicated to establish a relationship between laboratory tests and a decrease in performance in real diving. Moreover, it is very difficult to associate a diving accident with a marijuana intake given the shortness of storage in the blood of the active agent contained in the marijuana.
Proven risks
What is clearly stated, however, according to the American surgeon Ernest Campbell is the adverse effects of this drug on the lungs of divers, the smoke of this substance containing 50% more tar and carcinogenic agents than the smoke of tobacco. For this surgeon, marijuana, by dilating the bronchi and causing lung inflammation, would increase the risk of gas embolism. It also has a negative effect on the cardiovascular system, accelerating the heart rate, increasing blood pressure and increasing the risk of a heart attack.
Smoking joints in Indonesia and in countries with strict legislation
We do not aim at morality at all. However, it is easy to get cannabis or illicit substances in some diving destinations, which are conducive to relaxing moments by the sea. However, the laws of their countries can be very strict in terms of drug use. Indonesia or Thailand are particularly known for this and many leisurely tourists have found themselves in prisons after consuming a “simple bédo”. Beyond the practice of scuba diving in itself, during a diving trip, we strongly advise you to learn about the legislation in force.
There are many who denounce the dangers of cannabis use before diving, but evidence is lacking. Caution should be avoided, so avoid smoking a joint before diving!