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Individuals with addiction need treatment. The core component of opioid addiction treatment is medication. There are three FDA‐approved medications for opioid use disorder: methadone, buprenorphine, and naltrexone. Evidence for naltrexone in pregnancy is limited and therefore it is not recommended at this time. Methadone, a full opioid agonist, has been used in pregnancy since the 1960s and buprenorphine has been available in the US since 2002. Randomized trial and systematic review data demonstrate that both are safe and effective. Methadone must be dispensed from an opioid treatment program (OTP) and carries a small risk of overdose primarily during the initial phase of treatment. Buprenorphine can be dispensed from an OTP but is more often prescribed by providers who have obtained an “X waiver” from the Drug Enforcement Administration (DEA). Buprenorphine is a partial agonist and can precipitate withdrawal if given to a patient who is not already in withdrawal. Neonatal abstinence syndrome (NAS) is a possible side effect of both methadone and buprenorphine, although the severity and duration of NAS are less with buprenorphine.

Patients can be initiated on medication in either inpatient or outpatient settings at any gestational age. Both methadone and buprenorphine can be administered in inpatient settings by providers without DEA X waivers and by health systems without attached OTPs. Details regarding medication choice are detailed in Table 3.1. However, the hospital care team must ensure presence and availability of outpatient providers for continuing care.

Initial clinical assessment should include a Clinical Opiate Withdrawal Scale (COWS), other substance use history, and HIV and HCV testing. COWS is an 11‐item scale administered by a clinician which provides a summary measure of withdrawal. (There is a helpful online tool to assess COWS available at: www.mdcalc.com/cows‐score‐opiate‐withdrawal). Medication dosage is first titrated to treat withdrawal (see Table 3.2 for draft induction protocol). Stabilization occurs within days. Further dose increases may be needed to control craving. A goal of medication‐assisted treatment for opioid addiction is a clinically meaningful opioid “blockade”: the degree to which medications block the reinforcing effects of other self‐administered opioids. In other words, if a patient feels an effect from an opioid while receiving medication for opioid addiction, then a dose increase may be indicated.

Table 3.1 Medication choice for treatment of opioid use disorder in pregnancy and postpartum

	Benefit	Consideration
Methadone	No need for withdrawal for initiation May have better treatment adherence	Must be dispensed from an opioid treatment programRisk of overdose if rapid initial titration
Buprenorphine	Can be prescribed by waivered provider Newborns may have less severe neonatal abstinence syndrome	Risk of precipitated withdrawal

Table 3.2 Buprenorphine initiation protocol example

Source: Based on Wesson DR, Ling W. The Clinical Opiate Withdrawal Scale (COWS). J Psychoactive Drugs 2003;35(2):253–9.

Day 1:Document baseline Clinical Opiate Withdrawal Scale (COWS)Administer buprenorphine/naloxone (SL)aCOWS 8‐10: Give buprenorphine/naloxone 2/0.5 mgCOWS >10: Give buprenorphine/naloxone 4/1 mgRepeat COWS in 1–2 hours and repeat administration of buprenorphine as aboveTypical day 1 dose = 6–8 mg

Day 2:Administer COWS and total day 1 buprenorphineRepeat COWS in 1–2 hours and administer additional buprenorphine as aboveTypical day 2 dose = 8–16 mg

Medication for opioid addiction works. Recurrence rates for treated addiction are similar to other chronic conditions such as hypertension. Furthermore, much of the obstetric burden from substance use is from untreated rather than treated addiction. People with treated addiction have birth outcomes that are more like those without addiction than those with untreated disease.