Genetic predisposition accounts for 40-60% of the vulnerability to addiction, highlighting its nature as a medical condition.
Factors like early exposure, trauma, and socioeconomic conditions play critical roles in the development of SUD.
Stimulants are substances that increase central nervous system activity, producing heightened alertness, energy, and euphoria. This class ranges from widely used substances like caffeine and nicotine to highly addictive drugs like cocaine and methamphetamine, as well as prescription medications for ADHD. Understanding stimulant pharmacology and the unique challenges of stimulant use disorders is essential for comprehensive addiction care.
By the end of this module, you will be able to:
All stimulants increase catecholamine activity (dopamine, norepinephrine) in the brain:
| Drug | Primary Mechanism | Duration | |------|-------------------|----------| | Cocaine | Blocks DAT, NET, SERT (reuptake inhibition) | 15-30 min (smoked/IV) | | Methamphetamine | Blocks reuptake + reverses transporters | 8-12 hours | | Amphetamine | Blocks reuptake + releases stored catecholamines | 4-6 hours | | MDMA | Primarily serotonin release + some dopamine | 3-6 hours |
| Feature | Cocaine | Methamphetamine | |---------|---------|-----------------| | Source | Coca plant (natural) | Synthetic | | Mechanism | Reuptake blockade only | Reuptake block + transporter reversal | | Duration | Short (15-30 min smoked) | Long (8-12 hours) | | Metabolism | Rapid hepatic | Slow, partially excreted unchanged | | Neurotoxicity | Lower | Higher (damages dopamine neurons) | | Half-life | ~1 hour | ~12 hours |
Key Difference: Methamphetamine not only blocks dopamine reuptake but also reverses the transporter, actively pumping dopamine out of neurons. This creates a much larger and longer-lasting dopamine flood.
Stimulant users often engage in "binge" patterns:
Binge Phase (hours to days):
Crash Phase (1-3 days):
Withdrawal Phase (1-2 weeks):
| Route | Onset | Duration | Form | |-------|-------|----------|------| | Intranasal | 3-5 min | 15-30 min | Powder (hydrochloride) | | Smoked | 8-10 sec | 5-10 min | Crack (freebase) | | Intravenous | 10-15 sec | 15-20 min | Dissolved powder | | Oral | 10-30 min | 45-90 min | Chewed coca leaves |
Clinical Note: Faster onset = more addictive. Crack cocaine's rapid onset makes it highly reinforcing.
Desired:
Adverse:
Cardiovascular (leading cause of cocaine-related death):
Neurological:
Nasal (intranasal users):
Psychiatric:
When cocaine and alcohol are used together:
Methamphetamine has become a major public health crisis:
Desired:
Adverse:
Methamphetamine causes direct damage to dopamine neurons:
Recovery: Some neurological recovery occurs with sustained abstinence (months to years), but deficits may persist.
Severe dental decay characteristic of chronic meth use:
Causes:
Presentation:
Prevalence: Up to 40% of chronic users experience psychotic symptoms
Features:
Risk Factors:
| Drug | Brand Names | Indication | |------|-------------|------------| | Amphetamine/Dextroamphetamine | Adderall | ADHD, Narcolepsy | | Methylphenidate | Ritalin, Concerta | ADHD | | Lisdexamfetamine | Vyvanse | ADHD, Binge Eating |
Non-medical use of prescription stimulants is common among students:
Motivations:
Prevalence:
Physical:
Psychiatric:
Addiction:
Diagnostic Accuracy:
Cognitive Enhancement:
Prescriber Responsibility:
Unlike opioids, no FDA-approved medications for stimulant use disorder:
Contingency Management (CM):
Cognitive Behavioral Therapy (CBT):
Community Reinforcement Approach (CRA):
Matrix Model:
Under Investigation:
Priya, 32, presents to the ED with chest pain and palpitations. She admits to using cocaine at a party last night, which continued into a 2-day binge. She hasn't slept in 48 hours. ECG shows sinus tachycardia at 130 bpm. She is anxious and reports "feeling like something terrible is about to happen."
Discussion Questions:
Next Module: Cannabis & Hallucinogens: The Psychedelic Renaissance →
External links
Use one of the external tools below to explore "Stimulants: Cocaine, Methamphetamine & Prescription Drugs". Check clinical claims against approved sources.
External links
Use one of the external tools below to explore "Stimulants: Cocaine, Methamphetamine & Prescription Drugs". Check clinical claims against approved sources.