What controlled substance schedule are benzodiazepines (benzos) and opioids classified as?

Controlled Substance Classification of Benzodiazepines and Opioids

Most opioids are classified as Schedule II controlled substances, while benzodiazepines are typically Schedule IV controlled substances under the Comprehensive Drug Abuse Prevention and Control Act of 1970.

Opioid Classifications

Opioids are primarily categorized into two schedules:

Schedule II Opioids

• Higher potential for abuse with severe psychological or physical dependence
• Examples include:
  • Morphine (e.g., MS Contin)
  • Oxycodone (e.g., Roxicodone) and oxycodone combination products (e.g., Percocet)
  • Hydromorphone (e.g., Dilaudid)
  • Fentanyl (e.g., Duragesic patch, Actiq)
  • Oxymorphone (e.g., Opana)
  • Pure codeine 1

Schedule III Opioids

• Moderate to low potential for physical dependence and high psychological dependence
• Examples include:
  • Hydrocodone combination products with acetaminophen (e.g., Vicodin, Lortab) or ibuprofen (e.g., Vicoprofen)
  • Codeine combination products (containing 15 mg or less of codeine per dose) 1

Note: As of October 2014, hydrocodone combination products were reclassified from Schedule III to Schedule II due to increasing levels of abuse, though some of the evidence cited still refers to their previous classification.

Benzodiazepine Classification

• Benzodiazepines are classified as Schedule IV controlled substances
• Lower potential for abuse than Schedule II or III substances
• Examples include:
  • Diazepam (Valium)
  • Lorazepam (Ativan)
  • Clonazepam (Klonopin)
  • Alprazolam (Xanax) 1

Clinical Implications and Risks

Prescribing Restrictions

• Schedule II medications (most opioids):

  • Require written prescriptions
  • No refills allowed
  • Must be filled within a limited time period
  • Prescribers must have valid DEA registration
  • Special prescription forms often required 2

• Schedule IV medications (benzodiazepines):

  • Less restrictive prescribing requirements
  • Refills permitted (up to 5 refills in 6 months)

Combined Use Risks

• Concurrent use of benzodiazepines and opioids significantly increases risk of:

  • Fatal overdose (75-90% increased all-cause mortality) 3
  • Respiratory depression 1
  • Emergency department visits 4

• CDC guidelines strongly recommend avoiding concurrent prescribing of opioids and benzodiazepines whenever possible 1

Special Considerations

• Long-acting or extended-release Schedule II opioids (OxyContin, methadone, fentanyl patches) are indicated for chronic pain only and should not be used for acute pain 1, 2
• Extended-release opioids should only be used in opioid-tolerant patients 1
• When tapering patients on both benzodiazepines and opioids, it is generally safer to taper opioids first due to greater risks associated with benzodiazepine withdrawal 1

Conclusion

Understanding the controlled substance scheduling of these medications is essential for appropriate prescribing, as it reflects their abuse potential and the regulatory requirements that govern their use. The classification system helps guide clinical decision-making to minimize risks while providing appropriate pain management and treatment of anxiety disorders.