Exam 9: Psychomotor Stimulants Flashcards
Methamphetamine
Amphetamine with an added methyl group that helps resist metabolism by MAO and makes it more lipid soluble (better at entering the CNS)
Methylphenidate
Ritalin
Used to treat ADD
Acts on the Locus Ceruleus (area with the most NE producing neurons)
Can also affect dopamine areas (abuse potential)
Cathinone
Amphetamine-like molecule found in leaves of a plant in Africa and the Middle East
Analogs are found in “Bath Salts” which are snorted to produce amphetamine-like high
Ephedrine
Natural product found in herbal preps
Sympathomimetic agent
Can be used to cook meth
Modafanil and Armodafanil
Non-amphetamine stimulants
Used to treat narcolepsy and shift work disorder
Abused by students for their amphetamine-like effects
CNS effects of stimulants
- Arousal, make fullness (reticular activating system)
- Euphoria (WOO!!!) (some people get dysphoria)
- Delay fatigue-induced decline in performance (intellectual and motor)
Adverse effects of stimulants
- crashing
- tolerance, dependence (psychological and physical)
- Tactile Hallucinations (formication).
- Symptoms that mimimc paranoid schizophrenia (usually reversible)
- Appetite suppression
Peripheral effects of stimulants
Hypertension, tachycardia, arrhythmias, mydriasis
Decreased food intake, wasting
Dental/skin problems
Potential toxic neurological effect of stimulants
- Degeneration of the dopaminergic and serotonergic pathways in the brain
- Decreased levels of stored levels of DA in the reward centers (dependence)
Amphetamine mechanism
Enhance release of NE and DA
Cocaine mechanism
Inhibition of the uptake of NE and DA
General mechanisms of stimulants
- Enhance release or decrease uptake of NE and DA
2. Direct stimulation of alpha receptors in reward centers of the brain
How can you increase excretion of amphetamines?
Acidify the urine
Medical uses of amphetamines
Narcolepsy
ADD
Weight loss
What is different about crack compared to powdered cocaine?
It is fat soluble and taken by smoking
Positive effects of cocaine
Euphoria
Reinforcing effects on reward centers (causes seeking behavior)
Suppresses appetite
Negative Effects of Cocaine in the CNS
Paranoia, hallucinations, psychosis Craving Lethargy, fatigue Depression, anhedonia Irritability, hostility, anxiety
Peripheral effects of cocaine
Increased HR and BP Arrhythmias Stroke Sudden death Birth defects
Mechanisms of cocaine
CNS- Inhibition of reuptake of NE and DA resulting in stimulant and reinforcing effects respectively
Periphery- Inhibits NE reuptake resulting in sympathomimetic effects
What are drugs that could antagonize the effects of cocaine?
Antipsychotics tha tblock dopamine receptors
Effect of chronic cocaine use?
Inhibition of DA reuptake eventually results in depletion of DA in the presynaptic neuron
What are some treatments for cocaine dependence?
- Nutritional supplements that help rejuvenate DA stores
- L-DOPA
- Bromocryptine (DA agonist)
- Antidepressants (Bupropion) are less powerful DA reuptake inhibitors
- Certain opioids
Name 3 Methylxanthines
- Caffeine
- Theophylline
- Aminophylline
What are Theophylline and aminophylline used for?
Asthma (they relax the bronchioles)
What could you use to stimulate respiration in preterm infants?
Caffeine or theophylline
What are peripheral effects of methylxanthines?
Relax bronchioles
Stimulate gastric secretion (careful in patients with peptic ulcer disease)
Carcinogenic/teratogenic???-Controversial
3 mechanisms of methylxanthines?
- Phosphodiesterase inhibition
- Adenosine receptor blockage
- Calcium release
Uses of methylxanthines?
Asthma
Headache
Diuretics
Respiratory stimulation in preterm infants
Methyxanthine OD
Can lead to life threatening seizures or cardiovascular collapse
Name 2 spinal cord stimulants
Strychnine and Tetanus toxin
Strychnine
Glycine antagonist in the spinal cord and other CNS areas
Removes post synaptic inhibition and can cause severe seizures
Treat with diazepam
Tetanus toxin
Inhibits glycine release from Renshaw cells
Causes convulsions, tetany
