What are some examples of banned or restricted drugs?

Banned and Restricted Drugs

The most clinically relevant banned drugs include market-withdrawn medications like terfenadine (due to fatal cardiac arrhythmias), thioridazine (FDA black box warning for QTc prolongation), and ephedra/Ma Huang (cardiovascular risks), along with performance-enhancing substances prohibited in competitive athletics and illicit recreational drugs that pose immediate life-threatening risks. 1, 2, 3

Market-Withdrawn Medications (Banned from Clinical Use)

Cardiovascular Safety Concerns

• Terfenadine was withdrawn from the market due to potentially fatal cardiac arrhythmias (torsades de pointes), particularly when combined with CYP3A4 inhibitors like ketoconazole and erythromycin 1, 2
• Thioridazine carries an FDA black box warning and should be avoided due to severe QTc prolongation (25-30 ms mean increase), representing the highest risk among antipsychotics for sudden cardiac death 3
• Ephedra (Ma Huang) is banned due to cardiovascular risks including severe blood pressure elevation, stroke, myocardial infarction, and performance-enhancing effects 2, 4

Common Pitfall

The terfenadine case illustrates that even drugs with extremely low absolute incidence of adverse events (nearly 100 million prescriptions written) can be withdrawn when fatal arrhythmias occur, especially in patients with specific risk factors like drug-drug interactions or metabolic abnormalities 1

Performance-Enhancing Substances (Banned in Competitive Athletics)

Prohibited by World Anti-Doping Agency and Olympic Committees

• Anabolic-androgenic steroids are banned and may cause sudden cardiac death, psychiatric complications, and permanent organ damage 1
• Growth hormone is prohibited due to performance enhancement and lack of safety data in healthy athletes 1
• Red cell boosting agents (erythropoietin, blood doping) are banned due to thrombotic risks and unfair competitive advantage 1
• Systemic decongestants including pseudoephedrine and phenylephrine are banned (topical preparations allowed) 2
• Stimulants including amphetamines and methylphenidate require therapeutic use exemptions for legitimate medical conditions like ADHD 1

Medications Requiring Therapeutic Use Exemptions

Athletes must obtain pre-approval for medically necessary banned substances including β2-adrenergic agonists, glucocorticoids, stimulants (methylphenidate), and β-adrenergic blockers through their national governing agency 1

Restricted Weight Loss Medications

Short-Term Use Only (Maximum 12 Weeks)

• Phentermine is FDA-approved only for short-term use and is a Schedule IV controlled substance with abuse potential similar to amphetamines 1, 2, 5
• Diethylpropion and other sympathomimetic amines are restricted to 12 weeks maximum due to cardiovascular risks and abuse potential 2

Absolute Contraindications for Phentermine

These medications should be avoided in patients with coronary artery disease, uncontrolled hypertension, glaucoma, hyperthyroidism, and history of substance use disorder 2, 5

Critical Safety Warning

Phentermine is chemically and pharmacologically related to amphetamines, with documented cases of severe psychological dependence, psychosis clinically indistinguishable from schizophrenia, and fatal overdoses 5

Illicit Recreational Drugs (Life-Threatening Risks)

Immediate Discontinuation Required

• Cocaine causes sudden cardiac death, severe hypertension, myocardial infarction, and stroke requiring immediate cessation 1, 2, 6
• Methamphetamine produces severe blood pressure elevation, cardiovascular collapse, and psychosis 2, 6
• "Bath salts" (MDPV) are synthetic cathinones causing severe hypertension, hyperthermia, seizures, combative behavior, and cardiorespiratory collapse 2, 6, 7
• Synthetic cannabinoids ("K2," "Spice") are potent cannabinoid receptor agonists causing severe intoxication and overdose deaths 7

Clinical Recognition

Sudden changes in mood, weight loss, depression, disturbed sleep patterns, deteriorating performance, and loss of interest in social activities may indicate drug addiction requiring prompt intervention 8

High-Risk Cardiac Medications

Antiarrhythmics with Highest TdP Incidence (1-10%)

• Quinidine, disopyramide, procainamide (older sodium/potassium channel blockers) have well-documented torsades de pointes incidence from uncontrolled case series 1
• Sotalol, dofetilide, ibutilide (potassium channel blockers) have TdP incidence data from clinical trials and new drug applications 1

Non-Antiarrhythmic Drugs with Multiple TdP Case Reports

• Methadone has high-profile association with torsades de pointes, though absolute incidence is lower than antiarrhythmics 1
• Haloperidol causes QTc prolongation (7 ms mean), with higher risk via IV route, and 46% increased risk of ventricular arrhythmia/sudden cardiac death (adjusted OR 1.46,95% CI 1.17-1.83) 1, 3
• Erythromycin causes TdP almost always with high doses or IV route, often in patients with other risk factors 1
• Droperidol is widely used but implicated in multiple TdP case reports 1

Dose-Dependent Risk Pattern

For virtually all QT-prolonging drugs, risk increases with plasma drug concentration, with the notable exception of quinidine, which paradoxically causes TdP at low concentrations due to its potent IKr blockade 1

Drugs Requiring Careful Monitoring (Not Banned but Restricted)

Weight-Gain Promoting Medications to Minimize

When possible, provide alternatives for medications that promote weight gain including antipsychotics (clozapine, olanzapine, risperidone), tricyclic antidepressants, glucocorticoids, injectable progestins, anticonvulsants (gabapentin, pregabalin), and β-blockers (atenolol, metoprolol, propranolol) 1

Protease Inhibitors with Absolute Contraindications

Telaprevir and boceprevir have absolute contraindications with cardiac medications, ergot derivatives, benzodiazepines, and herbal products due to risk of torsades de pointes and other toxicities 2

Regulatory Context

Market Availability Despite Bans

Research demonstrates that 33% of weight loss supplements contain at least one banned ingredient, and 90% contain discouraged-use ingredients, with retail outlets dedicated to supplements having the greatest number of problematic products 9

Evolving Designer Drugs

Underground chemists continuously modify chemical structures of synthetic drugs to avoid legal regulation, making these compounds rapidly evolving and undetectable by traditional drug screening 7