Effect of Drugs and Disorder of the Nervous System

Effect of Drugs on the Nervous System

Drugs can affect the nervous system by altering impulse transmission across synapses. This occurs by:

Cannabis (marijuana):
- In low doses, cannabis acts as a depressant. It slows down coordination, perception, timing, and short-term memory, and causes mild euphoria. It can also cause anxiety, delusions, disorientation and hallucinations.
- Long-term use can weaken the immune system, impair mental functions, and reduce sperm and testosterone levels.

Cocaine:
- Prevents the normal breakdown of dopamine, a neurotransmitter linked to feelings of pleasure.
- When dopamine isn't broken down, the synapse keeps sending messages, causing euphoria. The body then produces less dopamine, leading to addiction as users need more cocaine to feel "normal."
- Over time, the body becomes tolerant to cocaine, so higher doses are needed to get the same effect.

Ecstasy:
- Causes nerve cells to release all their stored serotonin at once, which can damage axons.
- Serotonin controls temperature and mood. If body temperature reaches 43°C, e.g. from dancing, the blood can start to clot, which can be deadly.
- Ecstasy also impairs memory.

Parkinson's disease is a degenerative disease of the nervous system.
Symptoms:
- Shaking and trembling of hands and legs
- Difficulty walking
- Stiff and rigid body
Cause:
- The inability to produce the neurotransmitter dopamine in a part of the brain.
- This leads to difficulty in controlling muscular contractions.
Prevention:
- Currently, there is no known prevention for Parkinson's disease.
- Exposure to pesticides is thought to be a potential factor, so wearing protective clothing when handling pesticides is recommended.
Treatment:
- Physiotherapy and regular exercises can help manage symptoms.
- Drugs like levodopa are used to mimic dopamine's effects in the brain, improving muscle control.