Injection Drug Use Medication

Updated: Apr 19, 2022
  • Author: Hammad Khan, MD, MPH; Chief Editor: Glen L Xiong, MD  more...
  • Print

Medication Summary

The goals of pharmacotherapy are to reduce morbidity and to prevent complications.


Opioid replacement therapy

Class Summary

Individuals who have injected heroin or other opioids for long periods may need referral for opioid replacement therapy with methadone, buprenorphine, or buprenorphine/naloxone where such programs are available. In the United States, physicians who wish to prescribe buprenorphine must take a certification course. Levo-alpha-acetylmethadol (LAAM) has also been used for opioid replacement therapy, but use of LAAM has been less common because of concerns about severe QT prolongation secondary to LAAM.

Opioid replacement therapy reduces injecting drug use and thus reduces the mortality and morbidity associated with injecting drug use, including the transmission of HIV and HCV.

When individuals who are opioid dependent (including those who are on opioid replacement therapy) need analgesia, the clinician should be aware that these individuals may be tolerant to the analgesic effects of opioids; thus, they may require higher doses for pain control. Individuals taking naltrexone (an opioid antagonist) for opioid or alcohol dependence, also require higher doses of opioid analgesics to overcome the opioid blockade and provide pain relief.

Methadone (Dolophine)

Inhibits ascending pain pathways, diminishing the perception of and response to pain. In most countries, methadone is administered initially in the setting of a drug treatment program, both to prevent diversion (selling) of supply and to assure that counseling and other services also are provided.

Rate of dose increase and maximum dose often depend on program regulations and on federal and state regulations in the United States.

Patients who cannot take anything by mouth may be administered methadone IM, usually in a divided dose.

Buprenorphine (Subutex)

Mixed agonist-antagonist narcotic with central analgesic effects for moderate to severe pain. Used sublingually for the initial detoxification treatment of opioid addiction. Produces agonist/antagonist effects at the opioid mu receptor. The agonist effect is limited by a ceiling effect (ie, higher doses [>16 mg] do not produce more analgesia). The sublingual product is called Subutex.

Buprenorphine and naloxone (Suboxone)

Used sublingually for the maintenance detoxification treatment (unsupervised phase) of opioid dependence following induction with sublingual buprenorphine (Subutex). Contains both buprenorphine (an opiate agonist/antagonist) and the opiate antagonist naloxone. Naloxone has been added to guard against IV abuse of buprenorphine by individuals physically dependent on opiates.

Levomethadyl (ORLAAM)

Indicated for management of opioid dependence. No other recommended uses exist. In most countries, levomethadyl is administered initially in the setting of a drug treatment program, both to prevent diversion (selling) of supply and to assure that counseling and other services also are provided.


Opioid Reversal Agents

Class Summary

Inhibit opioid effects by inhibiting opioid agonists at receptor sites. FDA approval of extended-release IM naltrexone for the prevention of relapse to opioid dependence was based on data from a 6-month, multicenter, randomized, phase 3 study, which met its primary efficacy endpoint and all secondary efficacy endpoints. Once monthly treatment with extended-release IM naltrexone showed statistically significant higher rates of opioid-free urine screens compared with placebo (p< 0.0002).

Naltrexone (Revia, Vivitrol)

Used in combination with clonidine for rapid (4-5 d) detoxification.

Very effective long-acting opioid antagonist that was thought to be an ideal maintenance agent because it blocks receptor sites and, hence, opioid reinforcing properties. However, clinical results are not very promising when compared with methadone maintenance. Craving may continue during naltrexone maintenance. For groups of patients such as health care professionals or business executives for whom external incentives to stay away from drugs are important, naltrexone therapy has been very effective.

Long-acting parenteral suspension indicated for prevention of relapse to opioid dependence following opioid detoxification. Also indicated for treatment of alcohol dependence in patients who have been able to abstain from alcohol in an outpatient setting prior to treatment initiation.

Naloxone (Evzio, Narcan)

Naloxone is a short-acting, pure opioid antagonist that is used to reverse opioid intoxication. If patients do not respond to multiple doses of naloxone, consider alternative causes of unconsciousness. Need of ongoing substance abuse treatment should be established while caring for overdose. The injectable solution is available in vials and syringes (0.4 mg/mL, 1 mg/mL) for IV/IM/SC administration by healthcare providers. It is also available as an autoinjector (delivers 0.4 mg IM/SC) for home use by family or caregivers.