7.2 Opioid dependence
OPIOIDS
eiiiiF 273
Methadone hydrochloride
lINDICATIONS AND DOSE
Neonatal opioid withdrawal
▶BY MOUTH
▶Neonate:Initially 100 micrograms/kg, then increased in
steps of 50 micrograms/kg every 6 hours until symptoms
are controlled, doses may vary, consult local guidelines,
for maintenance, total daily dose that controls
symptoms to be given in 2 divided doses.DOSE EQUIVALENCE AND CONVERSION
▶See buprenorphine p. 274 for dose adjustments in
opioid substitution therapy, for patients taking
methadone who want to switch to buprenorphine.lUNLICENSED USENot licensed for use in children.
IMPORTANT SAFETY INFORMATION
Methadone oral solution 1 mg/mL is 2 ½ times the
strength of Methadone Linctus ( 2 mg/ 5 mL). Many
preparations of Methadone oral solution are licensed for
opioid drug addiction only but some are also licensed for
analgesia in severe pain.lCONTRA-INDICATIONSPhaeochromocytoma
lCAUTIONSFamily history of sudden death (ECG
monitoring recommended).history of cardiac conduction
abnormalities
CAUTIONS, FURTHER INFORMATION
▶QT-interval prolongationPatients with the following risk
factors for QT-interval prolongation should be carefully
monitored while taking methadone: heart or liver disease,
electrolyte abnormalities, or concomitant treatment with
drugs that can prolong QT interval; patients requiring
more than 100 mg daily should also be monitored.
lINTERACTIONS→Appendix 1 : opioids
lSIDE-EFFECTSDry eye.dysuria.hyperprolactinaemia.
hypothermia.intracranial pressure increased.mood
altered.nasal dryness.postural hypotension.QT interval
prolongation.torsade de pointes
SIDE-EFFECTS, FURTHER INFORMATIONMethadone is a
long-acting opioid therefore effects may be cumulative.
Methadone, even in low doses is a special hazard for
children; non-dependent adults are also at risk of toxicity;
dependent adults are at risk if tolerance is incorrectly
assessed during induction.
OverdoseMethadone has a very long duration of action;
patients may need to be monitored for long periods
following large overdoses.
lRENAL IMPAIRMENTAvoid use or reduce dose; opioid
effects increased and prolonged and increased cerebral
sensitivity occurs.
lTREATMENT CESSATIONAvoid abrupt withdrawal.
When used for neonatal opioid withdraw, reduce dose
over 7 – 10 days.
lDIRECTIONS FOR ADMINISTRATIONSyrup preserved with
hydroxybenzoate (parabens) esters may be incompatible
with methadone hydrochloride.
lPRESCRIBING AND DISPENSING INFORMATIONFlavours of
oral liquid formulations may include tolu.
lMEDICINAL FORMS
There can be variation in the licensing of different medicines
containing the same drug. Forms available from special-order
manufacturers include: tablet, capsule, oral suspension, oral
solution
Tablet
CAUTIONARY AND ADVISORY LABELS 2
▶Physeptone(Martindale Pharmaceuticals Ltd)
Methadone hydrochloride 5 mgPhyseptone 5 mg tablets|
50 tabletP£ 2. 84 DT = £ 2. 84 b
Oral solution
CAUTIONARY AND ADVISORY LABELS 2
▶Methadone hydrochloride (Non-proprietary)
Methadone hydrochloride 1 mg per 1 mlMethadone 1 mg/ml oral
solution| 100 mlP£ 0. 91 – £ 1. 00 DT = £ 0. 64 b| 500 mlP
£ 6. 18 DT = £ 3. 20 b| 2500 mlP£ 16. 00 – £ 32. 10 b
Methadone 1 mg/ml oral solution sugar free sugar-free| 50 mlP
£ 1. 04 DT = £ 1. 04 bsugar-free| 100 mlP£ 2. 08 DT =
£ 2. 08 bsugar-free| 500 mlP£ 6. 30 DT = £ 6. 30 bsugar-
free| 2500 mlP£ 31. 50 – £ 32. 50 b
▶Methadose(Rosemont Pharmaceuticals Ltd)
Methadone hydrochloride 10 mg per 1 mlMethadose 10 mg/ml oral
solution concentrate sugar-free| 150 mlP£ 12. 01 b
Methadone hydrochloride 20 mg per 1 mlMethadose 20 mg/ml
oral solution concentrate sugar-free| 150 mlP£ 24. 02 b
▶Metharose(Rosemont Pharmaceuticals Ltd)
Methadone hydrochloride 1 mg per 1 mlMetharose 1 mg/ml oral
solution sugar free sugar-free| 500 mlP£ 6. 82 DT = £ 6. 30 b
▶Physeptone(Martindale Pharmaceuticals Ltd)
Methadone hydrochloride 1 mg per 1 mlPhyseptone 1 mg/ml
mixture| 100 mlP£ 1. 08 DT = £ 0. 64 b| 500 mlP£ 5. 46
DT = £ 3. 20 b| 2500 mlP£ 27. 29 b
Physeptone 1 mg/ml oral solution sugar free sugar-free|
100 mlP£ 1. 08 DT = £ 2. 08 bsugar-free| 500 mlP£ 5. 46
DT = £ 6. 30 bsugar-free| 2500 mlP£ 27. 29 bBNFC 2018 – 2019 Opioid dependence 299
Nervous system4