Cannabis, or marijuana, is one of the most popular psychoactive substances worldwide, especially among teenagers.
Although the specifics of cannabis’ addictive qualities are still very much under debate, cannabis dependence disorder is officially classified in the DSM-5 and prolonged, heavy use of cannabis has been shown to cause some level of dependency.
Cannabis comes from the flowers of Cannabis sativa plants, which has oils with concentrations of tiny, fat-soluble, psychoactive molecules called cannabinoids.
The three main cannabinoids, tetrahydrocannabinol (also called THC), cannabidiol (also called CBD), and cannabinol (also called CBN), are each associated with unique psychoactive effects.
For example, THC is associated with high-grade recreational marijuana, and produces effects, like euphoria, analgesia, mild hallucinations, and an increased appetite.
Cannabidiol on the other hand does not have psychoactive effects and is commonly included in medical marijuana because it has a variety of effects including being analgesic, anti-inflammatory, anti-seizure, appetite stimulating, and anxiety-reducing.
To understand how cannabis works, let’s zoom in on a synapse of the brain to see how a stimulus response is induced generally, without drugs.
Normally, electrical signals, or action potentials, travel down the axon to the axon terminal, triggering the release of chemical messengers called neurotransmitters from synaptic vesicles into the synapse.
The neurotransmitters travel across the synapse and bind to receptors on the postsynaptic neuron, where they give the cell a message.
After the neurotransmitters have done their job, they unbind from the receptors and can simply diffuse away, be degraded by enzymes, or be picked up by proteins and returned to their release site in a process called reuptake.