Addiction Counselor's Guide to the Neuroscience and Pharmacology of Stimulants

This podcast episode, part of an addiction counselor training series, provides a comprehensive 2024 update on the pharmacology of stimulants, focusing on their impact on the neurological system and neurotransmitters. Dr. Donell Snipes explains that understanding the mechanism of action is crucial for comprehending why individuals might self-medicate or why stimulants affect people with conditions like ADHD differently. The presentation delves into the "big six" neurotransmitters—dopamine, serotonin, norepinephrine, Gaba, glutamate, and acetylcholine—emphasizing their interconnectedness and systemic functions. Dopamine is highlighted for its role in motivation, mood, energy, and the reward pathway, while norepinephrine is linked to the sympathetic nervous system, arousal, and concentration, and serotonin to mood, appetite, sleep, and various physiological processes. The core argument is that altering one neurotransmitter inevitably impacts the others, leading to widespread dysfunction.

The episode further elaborates on the nuances of nervous system dysfunction caused by stimulant misuse. It distinguishes between tolerance (receptors becoming unresponsive), cross-tolerance (sensitivity to similar drugs), reverse tolerance (receptors becoming hypersensitive), and physiological dependence (body relying on the drug). The concept of half-life is explained, noting how it varies by drug and is influenced by factors like age, liver health, and interactions with other medications metabolized by cytochrome p450 enzymes. Different methods of administration, from inhalation and injection to oral and transdermal, are discussed in terms of their speed of effect and implications for misuse. The speaker stresses that the oversimplified view of increasing or decreasing a single neurotransmitter often overlooks the complex interplay within the brain and body.

For addiction counselors, practical insights include recognizing self-medication behaviors, such as using caffeine to combat depression or antihistamine-induced brain fog, and understanding how these actions can further dysregulate the stress response. Counselors are advised to be cognizant of drug interactions, as common medications like SSRIs and antihistamines can compete with stimulants for metabolism, potentially intensifying stimulant effects or prolonging their presence in the body. Client education is emphasized, particularly regarding hydration levels for those on antipsychotics or other medications, as dehydration can alter blood plasma levels and trigger adverse events like psychotic episodes. The importance of screening clients for all forms of stimulant intake, including over-the-counter supplements, is also highlighted.

Broader implications cover the vast array of stimulants, from illicit substances like cocaine and methamphetamine to commonly used ones like caffeine and nicotine, as well as prescribed ADHD medications and decongestants. The discussion touches on the varied uses of stimulants, including preventing fatigue, suppressing appetite, improving ADHD symptoms, and even treating clinical depression or respiratory issues. The episode also critiques the drug scheduling system, pointing out perceived inconsistencies (e.g., Xanax as Schedule IV despite high abuse potential, or Schedule I classification of cannabis and LSD now being researched for therapeutic uses). Ultimately, the presentation underscores that stimulants trigger the HPA axis, releasing excitatory neurotransmitters and hormones like cortisol, which, while initially helpful, can lead to long-term disregulation and impact overall health and well-being.

"the mechanism of action the effect that any substance has whether it's a depressant or a stimulant has on the body is because of the way it impacts the neurological system the way it impacts those neurotransmitters"

"dopamine is not as much about the pleasure although it is somewhat involved in interpreting the stimuli but it is definitely involved in motivating our actions whether we're going to do it again or not"

"the neurotransmitters and there's a lot of them but the ones we mainly talk about are dopamine serotonin norepinephrine Gaba glutamate and acetyl choline those are your big six if you will and when one of those is altered it Alters everything else"

"serotonin has his grimy little mitts involved in everything it's in our gut it's in our brain it helps regulate our platelets it's in our um helps regulate our our heart rate"

"when people start misusing stimulants they're going to cause disregulation in the nervous system the HPA axis is going to start protecting itself and it's going to start usually becoming tolerant to that stimulus"

"cocaine increases the release of dopamine by 1,000% so that I want to do that again is amped up a th%"

"stimulants affect everyone differently based on their physical size their weight and their health as I mentioned earlier somebody who has poorly poorly fun functioning liver is going to have a harder time clearing the stimulants"

"stimulants are the most frequently used drugs in the world they're used to prevent fatigue they're an appetite suppressant they improve concentration in people with ADHD they're used to treat clinical depression"

"when people are taking stimulants what what it does is it binds to the enzyme that normally breaks that down and lets the dopamine just sit in that synaptic space for a lot longer than it's kind of supposed to"

"it binds to the dopamine reuptake transporter causing it to act in reverse and transport free dopamine out of the nerve terminal"