1. Drugs

2. Learning objectives What is drug misuse and drug abuse?
What is addiction?
Understand basic ideas about how drugs may influence transmission of action potentials from pre-synaptic neuron to post-synaptic neuron.
You do NOT need to memorize the individual effects of each of the drugs. You SHOULD be able to understand and explain such statements as “Drug X blocks the serotonin re-uptake protein on the pre-synaptic neuron”.
What are some effects of stimulants?
What are some effects of depressants?
What are some effects of cannabinoids? What is the active ingredient of marijuana?

3. Drug (ab)use

6. Drug use and misuse and abuse
Prescription drugs used for other purposes
Abuse
Use of drugs in an amount, a situation or a manner that causes problems or increases risk of problems

7. Dependence and Addiction
Dependence – Physiological – Body relies on the drug in order to avoid withdrawal
Addiction – Uncontrollable cravings, inability to control drug use (or behavior) despite doing harm to oneself and others

10. Stimulants Cocaine (and crack) Amphetamines (Adderall)
Methylphenydate (Ritalin, Concerta)
Methamphetamine (meth)
MDMA (ecstasy, also hallucinogenic)
Bath salts
Caffeine

13. Action of depressants
Depressants increase binding of GABA, which enhances GABA’s inhibitory effect

15. Increased dopamine release by this neuron
THC
GABA usually reduces amount of dopamine released
THC binds (and blocks) GABA.
Post-synaptic neuron releases more dopamine in next step
Increased dopamine release by this neuron

16. Opioids (Narcotics) Mimics endorphin (endogenous morphine)
Depresses some parts of the brain
Stimulate other parts, including reward pathways
Opioids – general term that includes:
Heroin, morphine, hydrocodone, oxycodone, fentanyl, methadone, codein, thebaine

17. Opioids Primary action of opioids Pathways affected
Opioids affect ion balance in pre-synaptic cell, preventing neurotransmitter release.
Pathways affected
Brain
Activates reward system (leads to addiction)
Brainstem
Depresses respiration (often the cause of death in overdoses)
Spinal chord
Dampens transmission of pain-related signals
Intestines
Reduces peristalsis, causing constipation

18. Opioids Overdose treatment Naloxone (Narcan) Acts very quickly
Binds to opioid receptors
Prevents binding by opioids
Acts very quickly

19. Opiate withdrawal Initial Withdrawal symptoms Muscle aches and spasms
Trouble sleeping
Racing heart
Sweating
Anxiety
Yawning
Hypertension
Fever
agitation

20. Opioid detox Medical Behavioral therapies
Methadone (Dolophine, Methadose) and Buprenorphine (Subutex)
Stimulate opioid pathways
Dampened ‘high’
Reduce withdrawal symptoms
Naltrexone (Depade, Revia)
Blocks action of opioids
Prevents getting high
Long-acting formulations (Vivitrol) administered once per month
Compliance often difficult because no high is created
Behavioral therapies
Contingency management – rewards for negative drug tests
Cognitive-behavior therapy – increase skills to cope with life stressors

21. LSD activates serotonin receptors
MDMA causes excessive serotonin and dopamine release
PCP affects many neurotransmitter systems
Affects region of brain dealing with perception.
May include mixing senses (‘hearing’ colors and ‘seeing’ sounds)
‘Trips’ may be pleasurable or a ‘bad trip’ may include terrifying thoughts or nightmares
Some are addictive (PCP, MDMA)
Some are not (LSD)
Some users develop chronic mental disorders