Diagnosis and Treatment of Cocaine & Methamphetamine Abuse/Toxicity
Acute Toxicity Recognition and Initial Management
For patients presenting with acute chest pain, cocaine and methamphetamine use should be considered as a primary cause, particularly in younger patients, as both drugs produce a hyperadrenergic state that can cause myocardial ischemia even without obstructive coronary artery disease. 1
Diagnostic Approach
- Obtain urine drug screening immediately - cocaine and methamphetamine typically test positive within 1-4 hours of use and remain positive for 2-4 days 1
- Perform 12-lead ECG - up to 70% of methamphetamine users have abnormal ECGs, most commonly tachycardia, with additional findings including hypertension, pulmonary artery hypertension, and cardiomyopathy 1
- Apply standard risk stratification for chest pain - the frequency of acute coronary syndrome is <10% among cocaine and methamphetamine users, and death is rare 1
Pathophysiology to Recognize
Both drugs block neuronal reuptake of norepinephrine and dopamine, creating catecholamine accumulation that produces: 1
- Dramatic increases in heart rate and blood pressure
- Coronary vasoconstriction with elevated myocardial oxygen demand
- Myocardial ischemia/infarction without obstructive CAD
- Cardiac arrhythmias and increased myocardial contractility
- Increased platelet aggregability and endothelial dysfunction
- Hypertensive vascular catastrophes (aortic dissection, cerebrovascular hemorrhage)
- Decreased myocardial perfusion and reduced coronary sinus blood flow
Acute Toxicity Treatment
Benzodiazepines are first-line for managing acute cocaine and methamphetamine toxicity symptoms including psychomotor agitation, tachycardia, and hypertension. 2
Critical Management Points
- Treat hyperthermia aggressively if present - it increases cocaine toxicity 2
- Do NOT use adrenergic blockers - they are contraindicated in acute cocaine toxicity 2
- Monitor continuously for cardiovascular complications throughout the acute phase 2
Definitive Treatment for Substance Use Disorder
The combination of Contingency Management (CM) plus Community Reinforcement Approach (CRA) is the most effective evidence-based treatment with a number needed to treat of 3.7 (95% CI 2.4-14.2) for sustained abstinence, demonstrating superior efficacy and acceptability for both short-term and long-term outcomes. 1, 3
Treatment Algorithm
- Contingency Management component: Provide tangible rewards (vouchers or prizes) contingent upon drug-free urine samples to create immediate positive reinforcement for abstinence 3, 4
- Community Reinforcement Approach component: Multi-layered intervention involving functional analysis, coping-skills training, and social, familial, recreational, and vocational reinforcements 3, 4
- This combination addresses both immediate behavioral reinforcement and underlying psychological/social factors that maintain addiction 3, 4
Evidence strength: CM plus CRA had the highest number of statistically significant results in head-to-head comparisons, being more efficacious than CBT alone (OR 2.44, P=0.045), non-contingent rewards (OR 3.31, P=0.010), and 12-step programs plus non-contingent rewards (OR 4.07, P=0.031) 1
Second-Line: Cognitive Behavioral Therapy 1, 3
- CBT has a number needed to treat of 10.5 (95% CI 5.8-53.6) 3
- More acceptable than treatment as usual but not significantly more efficacious than CM plus CRA 3
- If pharmacotherapy is used, CBT must be delivered concurrently, not sequentially - combined treatment shows benefit over usual care (effect sizes g=0.18-0.28) 3, 4
Pharmacological Considerations
No FDA-approved medications exist specifically for cocaine or methamphetamine use disorder - psychosocial interventions remain first-line treatment 3
- Medications such as bupropion, topiramate, and disulfiram have low-strength evidence and should only be considered as adjuncts to CM plus CRA, never as monotherapy 3
- Disulfiram has shown the most consistent effect to reduce cocaine use across multiple studies but remains investigational 3
Adjunctive Options (Not Standalone)
- 12-step programs: Not supported by strong evidence as standalone treatment but may be beneficial as adjunct 3
- Non-contingent rewards: Have not shown effectiveness and should be avoided 3
Critical Pitfalls to Avoid
- Do not rely solely on CM without CRA - this leads to relapse after treatment completion when behavioral reinforcement is withdrawn, as CM alone shows efficacy during treatment but effects are not sustained at long-term follow-up 3, 2, 4
- Do not use non-contingent rewards (providing rewards regardless of drug use status) - these have not shown effectiveness 3
- Do not prescribe adrenergic blockers for acute toxicity - they are contraindicated 2
- Do not implement pharmacotherapy without concurrent behavioral interventions - combined treatment is superior to medication alone 4
- Do not fail to provide long-term follow-up - sustained recovery requires continued support after initial treatment 3, 4
Monitoring Strategy
- Regular urine drug screens provide objective evidence of abstinence and are essential for implementing CM effectively 3
- Continued cardiovascular assessment throughout treatment given both drugs' cardiac effects 3, 2
- At least 3 months of follow-up recommended for longitudinal assessment 3
- Screen for co-occurring mental health conditions that may complicate treatment and require integrated approaches 3