What does cocaine do to the brain?
By Surya Solanki
Cocaine as a drug
Cocaine is produced from the leaves of the coca plant. The plant is cultivated in large quantities in South America. However, cocaine is an illicit drug and its production is a synthetic process. Coca leaves are mixed with an array of chemicals like sulfuric acid, kerosene, caustic soda and cement to produce a liquid, which is boiled to get “coka-paste” (solid form of cocaine).
Additionally, cocaine is a strong central nervous system (CNS) stimulant and causes a lot of activity in the brain. In this article, we look at the immediate effects of cocaine on the brain. Then, we invite your questions and feedback in the comments section at the end. In fact, we try to respond to all legitimate queries with a personal and prompt reply.
Cocaine and the brain
Inside the brain, cocaine acts upon a part of the brain called the ventral tegmental area (VTA). More specifically, cocaine interferes with the activity of the dopamine neurotransmitter. How?
Neurotransmitters are used by neurons to communicate. Dopamine acts both as an inhibitory and excitatory neurotransmitter- so it may rev up the speed of the electrical impulses in the neuron or reduce it. But the behavior of dopamine chemicals depend on the receptors they encounter. If the dopamine chemicals attach to the “feel good” chemical in reward pathway of the brain, we feel pleasurable. Similarly, dopamine can also trigger neurons that produce a feeling of panic or ones that cause impulsive behavior.
Normally, dopamine is re-absorbed via the dopamine transporter by the neuron that produced it. However, cocaine blocks the transporter. As a result, dopamine starts building up. In fact, cocaine blocks 60-77% of dopamine transporters in the central nervous system. And on average, in order to maintain a high, 47 sites must be blocked.
Additionally, cocaine also alters the level of serotonin (the neurotransmitter responsible for maintaining mood balance) in our brains. Even more, cocaine increases the amount of norepinephrine, which controls the body flight and fight response. Hence, the following effects of cocaine:
- increased blood pressure
- increased body temperature
- increased heart rate
- increased rate of respiration
The effect of cocaine varies
Depending upon the sites it blocks, the user experience may feel euphoric, paranoid, impulsive or talkative. This effect varies. While Sigmund Freud took cocaine in “small doses” to battle depression, large amounts of cocaine have been linked to the development of extreme paranoia, or even schizophrenia (the latter is linked with high levels of dopamine).
Method of administration
How quickly cocaine reaches the brain depends on the method of drug administration. Powder cocaine is usually snorted or injected. When snorted, the drug takes about three minutes to reach the brain. Whereas, when powder cocaine is injected into the veins, it takes about 14 seconds to reach the brain. When cocaine is smoked, it reaches the brain in seven seconds. Does cocaine work for everyone? Yes, usually it has a stimulant effect on all users, although euphoric effect can be subjective.
Are there differences between crack and powder cocaine?
Contrary to popular belief, crack cocaine and powder cocaine are the same drug. They have the “same biological effect” but differ in “chemical composition”. Powder cocaine contains hydrochloride salt, which prevents it from being burned. This salt can be removed by mixing the cocaine with water or baking soda. The resultant chemical so formed is called “crack cocaine”. Crack has a lower melting point (90 degree Celsius) than powder cocaine (180 degree Celsius) and hence, can be smoked. The name “crack” is derived from the sound the drug makes while being smoked.
Brain withdrawal after the high
Another characteristic of cocaine is that the body goes through immediate drug withdrawal, even after one use. A cocaine high may last for up to an hour (depending on the quality of the drug). When the effects of cocaine start to wane, dopamine levels become normal but can be experienced as a deficit. As a result, the main cocaine withdrawal side effect is that the user may feel “low” for a bit.
Continual use of cocaine is an artificial way of increasing dopamine and serotonin. Soon, the brain becomes rewired to produce less and less of the two chemicals and starts relying on cocaine to produce them. In this case, when the user stops doing cocaine, s/he faces depression, anxiety and other problems linked with serotonin and dopamine deficiency.
Cocaine and brain addiction
Although cocaine blocks dopamine chemicals in the synapse, after a period of time, the dopamine breaks down. Now the stock of dopamine needs to be replenished. Otherwise the user will feel depressed and “low”. The natural process of dopamine replenishment takes time. As a result, the user starts craving the drug. This is how addiction starts.
Questions about cocaine and the brain?
Do you still have questions about how cocaine acts on the brain? Please leave your questions below. We’ll do our best to respond to you personally and promptly.
Reference Sources: TSRI
Photo credit: Allan Ajifo