Electrical signals in the brain are sent using chemicals called neurotransmitters. All addictive drugs affect the production, release, or elimination of neurotransmitters. The major Neurotransmitters implicated in addiction are noted below.
Serotonin
Serotonin (5-hydroxytryptamine or 5-HT) is synthesized from dietary tryptophan and its primary function is regulation of sleep and mood. Low levels of serotonin have been associated with mood disorders such as depression.
Medications called specific serotonin reuptake inhibitors (SSRIs), such as Prozac and Zoloft, increase serotonin levels but can be very dangerous. You should consider taking the essential amino acid trytophan instead. Check with a holistic doctor for advice.
Norepinephrine (NE)
NE’s common function is associated with arousal and alertness. It is synthesized from the essential amino acid tyrosine. The levels of NE fluctuate throughout the day and therefore there are periods when we feel more awake and alert, while at other times we are tired and sleepy.
Certain drugs of abuse, such as stimulants or “uppers”, increase alertness and arousal and cause talkativeness, restlessness, and agitation because of their action on NE systems.
Dopamine
Dopamine release gives us the experience of pleasure and therefore causes us to want to repeat the behaviors necessary to acquire the reward in the future.
It’s interesting that amphetamine and cocaine both increase the amount of dopamine. However, cocaine achieves this action by preventing dopamine reuptake, while amphetamine helps to release more dopamine.
So, these drugs with similar effects produce their actions through entirely different processes. In turn, addiction to the two drugs may call for somewhat different types of addiction treatment.
GABA
Gamma aminobutyric acid (GABA) is synthesized from glutamate (an amino acid) and is found in very high concentrations throughout the brain. It is considered an “inhibitory neurotransmitter”. Because GABA has inhibitory effects on neurons, any drug that increases the actions of GABA will decrease general brain activity and can be considered a “downer” or depressant. Depressants include alcohol, sleeping pills such as Ambien, muscle relaxants such as Valium, and barbiturates such as Secobarbital. Some depressants are very powerful and can cause coma or death.
The Most Addictive Drugs
Different drugs have different effects on the neurotransmitters. For instance, cocaine and methamphetamine are much more addicting than THC (marijuana) because they increase dopamine levels more quickly and to a greater extent.