Contraindications (reasons to reevaluate treatment) and warnings:
• Although the high potency of extracts is their main attraction for many individuals, this high potency also carries with it an increased risk of side-effects. THC use quickly results in the development of a tolerance to many of the effects of cannabis. A high tolerance will require significantly higher doses to achieve the same effects that smaller doses would have achieved before tolerance was developed.
• Higher doses cause tolerance to increase more rapidly.
• A single dose of an extract can be incredibly potent. Some negative cognitive effects are more common with these types of extracts. Paranoia, anxiety, memory loss, loss of motor control, and transient narcolepsy are all potential side effects.
• Repeated high-dose use of cannabis can lead to cannabinoid hyperemesis syndrome. This is a relatively rare condition that causes uncontrollable vomiting (emesis), usually occurring early in the morning after a large amount of consumption the previous evening. Once an episode of cannabinoid hyperemesis has occured, future episodes are significantly more likely to occur in future. The high-dose/high-tolerance nature of extracts can increase the likelihood of developing this syndrome.
Improperly prepared extracts
• Improperly purged extracts can contain residual solvents. This can lead to a number of health effects, and can cause the container extracts are stored or transported in to leach contaminants into the extract.
• It is very difficult for the end consumer to know the quality standards that and extract was held to during its production. There are numerous ways that an extract can come to contain undesirable impurities (e.g., butane reacts with PVC piping, impurities in the cannabis being concentrated, etc…).
Respiratory distress associated with various methods
• Various methods can cause respiratory irritation if caution is not taken. Pipes, bongs, and any form of pre-heated element can lead to the inhalation of very hot air and dense smoke.
Increased legal risk
• Extracts carry significantly more serious punishments in Canada for possession and trafficking than does unrefined cannabis.