Module 7: The maintenance phase of opioid agonist treatment Flashcards
maintenance phase – what is it?
stable on OAT – titration complete, most cravings gone, no withdrawal
OUD – relapse is expected….
- early in dose titration phase (initiation), but also any time
- brief or prolonged or episodic
considerations for prescribing carries (i.e. when to do it)
- UDT clear
- safe housing with locked storage
- clinical stable (OAT is therapeutic)
- understand risk of diversion
- signed carry agreement
bup/nlx – timeline for prescribing carries
no prescribed timeline
- initiation after stabilisation, and 1 clear week of UDS
- start with 1 carry per week
- increase by 1 carry each week while clear UDS
- to a max 13 carries
can give more carries for compassionate or if long-term stability reasons
when and how to reduce carries - bup/nlx
- reduce by 1 per week if positive UDT or other concerns
methadone – timeline for initiating carries
- initiate carries at 2 months stability + negative UDT (CAMH 2021) or 1 month (Selby 2022)
- increase carries by 1 per week every 2 weeks if stable + negative UDT
- max 6 carries per week
give more carries for compassionate use or long-term stability (up to 13)
SROM – initiating carries
only under exceptional circumstances (case-by-case, very stable or witnessed dosing is impediment)
iOAT – initiating carries
none
Should OAT dose be increased if cravings occur?
Not necessarily. OAT dose should primarily control withdrawal symptoms, but an increase can be tried if cravings are the only concern.
Cravings can occur because of HALT (hungry, angry, lonely, tired) and so should be addressed therapeutically (med increase won’t help)
What are the psychological reasons for cravings (hint: there is an acronym)
Cravings can occur because of HALT (hungry, angry, lonely, tired) and so should be addressed therapeutically (med increase won’t help)
bup/nlx - re-induction after prolonged missed days
|Missed days | Dose | Suggested adjustment | |---------------|-----------------------|-----------------------| | 6–7 days | > 8 mg/2 mg | Restart at 8 mg/2 mg | | > 7 days | > 8 mg/2 mg | Restart at 4 mg/1 mg |
| ≥ 6 days | 6 mg/1.5 mg–8 mg/2 mg | Restart at 4 mg/1 mg |
≥ 6 days | 2 mg/0.5 mg–4 mg/1 mg | No change |
bup/nlx – restarting after missed doses (general points)
during initiation: reassess immediately
during maintenance:
- up to 5 days, then no change
- 6+ days, then re-initiation based on dose
methadone – restarting after missed doses
if 1-2 days missed, no dose change
if 3-4 days missed, then:
- if 30mg: no change
- if 30-60mg: restart at 30mg
- if >60mg: restart at 1/2 previous dose, reassess daily, increase by 10mg/day max
if 5+ days missed, then re-initiation as per guidelines
SROM – restarting after missed doses
- 1 day missed: no change
- 2 days missed: 40% reduction
- 3 days missed: 60% reduction
- 4 days missed: 80% reduction or starting dose if higher
- 5+ days: restart at 60mg
iOAT – restart after missed doses
1 day: no chage
2 days: reduced dose
3 days: retitration
OAT: if client is appears overmedicated, should dose be given?
no, pharmacist must withhold (risk of overdose)
prescriber must reassess
send to ER if needed
symptoms of opioid overdose
drowsiness / somnolence
sweating
pinpoint pupils
emotional lability
slurred speech
replacement doses of OAT: indications
- vomited methadone: replace up to 50% dose, give antiemetic, sip
- vomited bup/nlx: no issue
- vomited SROM: optional replacement
- lost or stolen carries: no replacement. consider reducing carries. report to police.
switching from bup/nlx to methadone
do it when bup/nlx not effectively controlling withdrawal
1. stop bup/nlx
2. next day, initiate methadone
3. titrate as usual (caution at start, as bup wears off then methadone effect increases)
switching from methadone to bup/nlx
do it when client wants greater flexibility, or has s/e
1. taper methadone to 20-30mg / day
2. stop methadone for 48-72 hours
3. initiation/titrate bup/nlx when moderate withdrawal (use microdosing)
consider starting SROM for 5 days after methdone stop and before starting bup/nlx
switching from methadone to SROM
- prescribe SROM dose at 1:4 methadone:SROM (e.g. 60mg methadone + 240mg SROM)
- titrate upwards as necessary to target 1:6 to 1:8
when is treatment complete?
- when client requests
- high risk of relapse and mortality if OAT is stopped
- gradual taper is more successful
bup/nlx – tapering
maximum rate of taper (slower as client needs it) :
- if dose 16+mg, taper 2mg every 1-2 weeks
- if dose 8-16mg, taper 1mg every 1-2 weeks
- if dose 1mg, reduce to 0.5mg x 1 week, then 0.25mg x 1 week, then stop
use bup patch for final taper.
methadone – tapering
- Slow taper: 5% every 2–4 weeks, with a 4–8 week period in between each taper.
- Consider more frequent small tapers as an alternate to a large taper with long periods. For example, taper 1 per cent on consecutive weeks.
if dose <30mg:
- taper 2mg every 2–4 weeks.
- Make tapers as slow as 1–2 milligrams every 1–2 weeks if necessary.
OAT and pain management considerations
- follow the pain ladder
- use pure opioid agonists to avoid withdrawal
- avoid CNS depressants (e.g. gabapentin)
- avoid opioids misused in the past
bup/nlx and methadone drug interactions
CNS depressants
CYP450 interactions
QTc prolonging agents
ECG monitoring during OAT
methadone is QTc prolonging (is bup/nlx?)
1. baseline ECG (if possible)
2. ECG if dose >120mg and every multiple of 20mg increase
3. ECG if QTc prolonging condition (e.g. vomiting) or drug/med used that prolonges QTc
- discuss risks if QTc 450-500ms, reduce if possible (otherwise don’t!)
- if >500ms, discuss switch to bup/nlx, consider consult cardiology
OAT and pregnancy
- risks of OAT outweighed by benefits (fewer intoxication/withdrawal cycles)
- breast-feeding okay
- advise re: neonatal abstinence syndrome (and likely hospital stay)
- bup/nlx > methadone during pregnancy
- methadone increase in 3rd trimester (increase body volume) and decrease after
OAT and pregnancy
- risks of OAT outweighed by benefits (fewer intoxication/withdrawal cycles)
- breast-feeding okay
- advise re: neonatal abstinence syndrome (and likely hospital stay)
- bup/nlx > methadone during pregnancy
- methadone increase in 3rd trimester (increase body volume) and decrease after
