Opiates
|
Codeine, Morphine, Oxycodone, Hydromorphone, Hydrocodone, Meperidine, Methadone, Fentanyl,
Heroin, Buprenorphine, LAAM |
|
|
Routes |
·
Oral, intramuscular (IM), intravenous (IV), transdermal, smoking |
|
Safe Limits |
Women taking moderate doses of prescribed opiates with no
evidence of dependence should continue their medication May need to observe neonate for withdrawal even with
therapeutic doses If tapering attempted, it should be considered only in
second trimester, as theoretical risks higher in first and third trimesters
(See below for complications of withdrawal) |
|
Symptoms of Intoxication |
·
Euphoria, sense of inner peace, fatigue,
confusion, drowsy, "nodding off" ·
Pinpoint pupils, shallow breathing with
decreased respiratory rate |
|
Symptoms of Overdose |
·
Drowsy, slurred speech, ataxic, decreased
respiratory rate |
|
Treatment of Overdose |
·
!! Medical EMERGENCY for mother and
fetus ·
ABCs: establish an airway and support adequate
respirations ·
Naloxone IV should
be administered if spontaneous respirations do not recover - titrate against
clinical signs ·
Assess fetal status (method subject to
gestation) and consult a specialist |
|
Symptoms of Withdrawal |
·
Flu-like symptoms ("dope sick"):
nausea, vomiting, diarrhea, sweating, myalgias,
chills, rhinorrhea, runny eyes, piloerection ·
Psychological symptoms: insomnia, anxiety,
strong drug cravings, dysphoria ·
Pregnancy-specific symptoms: abdominal
cramping, uterine irritability |
|
Complications |
·
Can cause uterine irritability leading to
increased risk of spontaneous abortion, preterm labour,
fetal hypoxia and fetal death ·
High risk of relapse to opiod
use |
|
Maternal Withdrawal Management |
·
Offer symptomatic therapy for nausea,
vomiting, myalgias until symptoms resolve or until
methadone becomes effective ·
Start methadone (see Initiation below) or buprenorphine (see below) ·
Can use morphine 5-10 mg po
q 4-6 h prn until methadone available ·
Clonidine:
CONTRAINDICATED during pregnancy ·
NSAIDs:
CONTRAINDICATED during third trimester |
|
Fetal Effects |
·
Direct effect on fetal growth leading to
intrauterine growth restriction and low birth weight (documented in both
animal and human studies) |
|
Maternal Effects |
·
Higher rates of obstetrical and medical
complications (particularly with injection opiate use) such as HIV,
hepatitis, STDs |
|
Management of |
·
Pregnant women who are physically and
psychologically dependent on opioids, should be
offered opiod replacement therapy (methadone or buprenorphine) – follow provincial guidelines for prescribing
methadone or buprenorphine [the latter currently
under development] ·
Rationale for use: benefits of opioid replacement therapy outweighs risks of untreated opioid dependence in pregnancy – decreased illicit
opiate use and cravings, decreased withdrawal symptoms and signs, improved
maternal health status and compliance with prenatal care, reduced fetal and
neonatal complications |
|
Buprenorphine |
|
|
Methadone Protocol |
Inpatient Initiation ·
Admit to hospital, expected length of stay ~
5-7 days ·
Advise patient to stop illicit opioid use ·
Administer methadone 10-20 mg po at onset of withdrawal symptoms, then doses of 5 mg po q 4-6 h prn for ongoing
withdrawal symptoms to a maximum of 35 mg in 24 hours on day 1 ·
Next day, administer previous day’s
total dose as a single morning dose then 5 mg po q
6 h prn to a maximum of 45 mg in 24 hours on day 2 ·
Do not increase beyond 45 mg on days 3-5 ·
Hold dose if drowsy and watch for symptoms of
intoxication (See above) ·
Discharge home when stable on one daily dose (i.e.,
dose lasts for ~24 hours and no further prn doses
needed) Outpatient Initiation ·
Consider if inpatient treatment not available
or patient not able to be admitted to hospital ·
Follow same protocol as outlined in MMT guidelines for outpatient initiation Outpatient Follow-up (after initiation) ·
Increase dose by 5-10 mg every 5-7 days if withdrawal
symptoms or cravings continue ·
Optimal dose does not cause sedation and lasts
24 hours without symptoms ·
Rate of methadone metabolism increases in
third trimester causing withdrawal symptoms, dose should be increased by
10-15 mg, and/or split into twice-daily dosing (in a 60:40 or 50:50 ratio) if
withdrawal symptoms continue ·
Use caution with doses >120 mg per day ·
Consider consulting a physician with
experience in caring for methadone-maintained pregnant women |
|
Fetal Assessment in Pregnancy |
·
Consider NST and/or BPP for assessment of fetal well-being ·
NST: methadone leads
to decreased beat-to-beat variability, decreased fetal movements and
suppresses fetal heart rate accelerations ·
BPP: suppressed
fetal breathing seen with methadone use |
|
Labour and Delivery
Issues |
·
Continue with regular dose of methadone or buprenorphine during labour ·
Adequate analgesia required - may need larger
and/or more frequent doses because of tolerance ·
If not on methadone: treat with morphine if presenting
with withdrawal symptoms |
|
Postpartum Issues |
·
May need dose reduction of methadone or buprenorphine in first few days or weeks postpartum ·
Prescribe adequate analgesia; do not discharge
with more than few days supply of opiates – use caution when
prescribing codeine preparations to breastfeeding mother ·
Neonates should be observed for withdrawal for
at least 4-5 days in hospital ·
Close follow-up of mother and infant
recommended |
|
Breastfeeding |
·
Methadone and buprenorphine
enter breast milk, although only a small amount detected ·
Breastfeeding ad lib is safe regardless of
dose ·
Women using illicit opioids
should consider benefits vs. risks of breastfeeding |
|
Neonatal Withdrawal |
·
Some babies of women using opiates will
experience neonatal withdrawal ·
Symptoms include gastrointestinal (vomiting,
watery stools), central nervous system (high-pitched crying, tremors,
abnormal muscle tone), metabolic (poor weight gain), vasomotor and
respiratory effects ·
Management of neonatal withdrawal depends on
availability and comfort level of local health care facility and training
level of staff (e.g., rooming-in, nursery or NICU
admission) ·
Encourage maternal bonding and breastfeeding
regardless of venue ·
Rooming-in, under care of supportive nursing
staff, may help reduce prevalence and severity of neonatal withdrawal and
promote bonding ·
If infant displays significant withdrawal
symptoms, may require treatment with morphine and consultation with pediatrics |