Drug Effects & Neurotransmitters

Dopamine

• Natural “Reward System”

• Critical to learning and desire.

• Most commonly associated with our “pleasure” system.

• Crucial in encoding of sport-oriented motor skills.

• Disorders with dopamine levels are linked to problems with memory, attention, problem-solving, social anxiety, bipolar, depression, ADD, Parkinson’s disease, and schizophrenia.

Serotonin

• Plays important role in regulation of body temperature, mood, sleep, sexuality, appetite and vomiting.

• Low levels of serotonin are found in people with depression, bipolar disorder, anxiety disorders, migraines and irritable bowel syndrome.

• Sunlight can naturally increase serotonin release!

Norepinephrine

• Part of your “fight-or-flight” response.

• Commonly called adrenaline.

• Released at times of stress.

• Excitatory to many regions of the body and brain.

• Plays a large role in attention and focus.

• Changes in normal levels are linked to ADD and depression.

Endorphins

• Released to inhibit/stop pain receptors.

• This is the brain’s own Morphine.

• Released at times of intense exercise or severe injury.

GABA

• The chief inhibitory neurotransmitter of of the CNS.

• Stops most neurons by creating a hyperpolarization.

• Increased GABA causes relaxation, anti-anxiety and anti-convulsive effects.

Histamine

• Released by white blood cells to increase blood vessel diameter (vasodilation).

• Increases brain activity.

• Anti-histamines are common over the counter cold medicines – that will cause drowziness.

• Many anti-histamines are chemically altered to produce methamphetamines.

Example of Anti-depressant Medication Action: NARI or MAOA inhibitors

Why is drug use dangerous to normal neurotransmitter function?

• Can cause excess neurotransmitter release.• Can act to block NT receptors.• Can block NT uptake/removal.• Can stop normal NT production (too much or too

little) for the long-term.• Can damage normal NT receptors (create too many

or have too few) for the long-term.• Can impair development of permanent neuron

connections, critical to learning and pleasure for the long-term.

• All of these NT problems lead to a variety of neurological disorders and mental illness.

Cocaine’s Action on a Neuron

Illegal Drugs and the NTs they affect.

• Marijuana = +dopamine, +serotonin, +GABA, - norepinephrine.

• Ecstasy – +serotonin, +dopamine

• Methamphetamine = +dopamine

• Cocaine = +dopamine, +norepinephrine and +serotonin

Legal Drugs and the NTs they affect.

• Vicodin – mimics endorphin.

• OxyContin – mimics endorphin.

• Alcohol – +GABA, -ACH, +endorphin

• Nicotine – +dopamine, +norepinephrine

• Caffeine – blocks Adenosine (an inhibitory NT) in CNS.