opioid dependence Flashcards
untreated heroin dependence shows early withdrawal symptoms within how many hours?
8 hours
Untreated heroin dependence shows early withdrawal symptoms within 8 hours, with peak symptoms at …..hours
36-72 hours
symptoms of untreated heroin dependence subside substantially after how many days?
5 days
what two drugs are used as opioid substitution therapy
methadone
buprenorphine
substitute medicine should be commenced with the following regimen
short period of stabilisation
followed by withdrawal regimen or by maintenance treatment
maintenance treatment has the following advantages
- enables pt to achieve stability
- reduces drug use
- reduces crime
- improves health
maintenance treatment needs to be reviewed regularly to ensure
pt continues to benefit
when should you attempt withdrawal regimen after stabilisation with methadone or buprenorphine
only after careful consideration
enforced withdrawal is ineffective for …
sustained abstinence and it increases risk of pt relapsing and subsequently overdosing because of loss of tolerance
complete withdrawal from opioids usually takes how long in an in-pt or residential setting, and how long in a community setting?
4 weeks
12 weeks
when should withdrawal regimen be stopped and maintenance therapy resumed at optimum dose?
(3 points)
if abstinence not achieves, illicit drug use resumed, or pt cannot tolerate withdrawal
following successful withdrawal, further support and monitoring to maintain abstinence should be provided for a period of at least…
6 months
patients who miss 3 days or more of their regular prescribed dose of opioid maintenance are at risk of overdose because of … so what should you consider
loss of tolerance
consider reducing dose in these pt
if a pt misses 5 or more days of treatment, what is recommended before restarting substitution therapy? and which drug is it particularly important in?
an assessment of illicit drug use is also recommended before restarting substitution therapy
this is particularly important for patients taking buprenorphine because of the risk of precipitated withdrawal
why is buprenorphine preferred by some patients?
less sedating than methadone
buprenorphine may be more suitable for employed patients or those undertaking other skilled tasks such as driving because…
less sedating than methadone
this drug is safer when used in conjunction with other sedating drugs and has fewer drug interactions
buprenorphine
dose reductions may be easier with this drug because withdrawal symptoms are milder, and pt generally require fewer adjunctive meds, there is also a lower risk of overdose
buprenorphine
this drug has a lower risk of overdose
buprenorphine
….. can be given on alternate days in higher doses and requires a shorter drug free period than with ….. before induction with naltrexone for prevention or relapse
Buprenorphine can be given on alternate days in higher doses and it requires a shorter drug-free period than methadone hydrochloride before induction with naltrexone hydrochloride for prevention of relapse.
pt dependent on high doses of opioids may be at increased risk of precipitated withdrawal. precipitated withdrawal can occur in any patient if …. is administered when other opioid agonist drugs are in circulation
buprenorphine has a very high affinity for the mu receptor and will displace any other opioid on the receptor, thereby causing precipitated opioid withdrawal.
If precipitated withdrawal occurs, it stays within …. hours of the first buprenorphine dose and peaks at around ….
starts within 1-3 hours
peaks at around 6 hours
what adjuvant therapy may be required if precipitate opioid withdrawal symptoms are severe?
non-opioid adjuvant therapy e.g. lofexidine hydrochloride
to reduce the risk of precipitated withdrawal with buprenorphine, the first dose should be given when the patient is exhibiting signs of withdrawal, or …. hours after the last use of heroin (or other short acting opioid), or …. hours after last dose of methadone
6-12h after last use of heroin (or other SA opioid)
24-48h after last dose of methadone
it is possible to titrate the dose of this drug within one week (which is more rapidly than with the other drug), but care is still needed to avoid toxicity or precipitated withdrawal; dividing dose on first day may be useful
possible to titrate dose within one week for buprenorphine, which more rapidly than with methadone
this combination preparation can be prescribed for pt when there is a risk of dose diversion for parenteral administration - and why?
buprenorphine with naloxone
the naloxone component precipitates withdrawal if the preparation is injected, but has little effect when preparation is taken sublingually
who would you give buprenorphine with naloxone to and why?
pt when there is a risk of dose diversion for parenteral administration
naloxone component precipitates withdrawal when it is injected, but has little effect when taken SL
what is an option when there is a risk of diversion of opioid substitution medicines, or difficulty with adherence to daily supervised opioid substitution medication?
buprenorphine prolonged release injection
when can you consider buprenorphine prolonged release injection
Where there is a risk of diversion of opioid substitution medicines, or difficulties with adherence to daily supervised opioid substitution medication
drug action of buprenorphine
opioid receptor partial agonist (has both agonist and antagonist properties)
this drug has both agonist and antagonist properties - opioid receptor partial agonist
buprenorphine
drug action - methadone
long acting opioid agonist
methadone is usually administered as a …
single daily dose as methadone oral solution 1mg/ml
which pt may prefer methadone due to its more pronounced sedative effect? (3)
- long history of opioid misuse
- abuse variety of sedative drugs and alcohol
- increased anxiety during withdrawal of opioids
methadone is initiated at least …. hours after last heroin dose, provided that there is objective evidence of withdrawal symptoms
8 hours
Methadone hydrochloride is initiated at least 8 hours after the last heroin dose, provided that there is…
objective evidence of withdrawal symptoms
when may a supplementary dose of methadone on the first day be considered?
if there is evidence of persistent opioid withdrawal symptoms
why may titration to optimal dose in methadone maintenance treatment take several weeks?
- long half life so plasma conc progressively rise during initial treatment even if pt remains on same daily dose
- dose tolerated on first day may become toxic on third day as cumulative toxicity develops
how many days does it take for plasma concentrations to reach steady state in patients on stable dose of methadone, and why
3-10 days due to its long half life
should you acutely withdraw opioids in pregnancy
no, can cause foetal death
Acute withdrawal of opioids should be avoided in pregnancy because..
can cause foetal death
why is opioid substitution therapy recommended during pregnancy
lower risk to foetus than continued use of illicit drugs
which drug is not licensed for use in pregnancy
buprenorphine
If a woman who is stabilised on methadone hydrochloride or buprenorphine for treatment of opioid dependence becomes pregnant, what should you do
continue therapy (buprenorphine not licensed in pregnancy)
should you choose a withdrawal regimen in pregnancy?
- avoid in 1st trimester - increased risk of spontaneous miscarriage
- withdraw gradually in 2nd trimester, dose reductions every 3-5 days
- not recommended in 3rd trimester because maternal withdrawal, even if mild is associated with foetal distress, stillbirth and risk of neonatal mortality
if illicit drug use occurs whilst withdrawing therapy in pregnancy, what do you do
patient should be re-stabilised at the optimal maintenance dose and consideration should be given to stopping the withdrawal regimen.
withdrawing regimen is not recommended in these trimesters of pregnancy because..
avoid in 1st, increased risk of spontaneous miscarriage
not recommended in 3rd, as maternal withdrawal (even mild) is associated with foetal distress, stillbirth and risk of neonatal mortality
drug metabolism may be increased in this trimester so it may be necessary to either increase dose of methadone or change to BD consumption (or combination of both strategies) to prevent withdrawal symptoms from developing
3rd trimster
drug metabolism can be increased in 3rd trimester so what may you need to do
either increase the dose of methadone hydrochloride or change to twice-daily consumption (or a combination of both strategies) to prevent withdrawal symptoms from developing
when should you monitor neonate for respiratory depression and signs of withdrawal ?
if mother is taking high doses of opioid substitute
if mother is prescribed high doses of opioid substitute, what do you need to monitor in neonate
respiratory depression and signs of withdrawal
signs of neonatal withdrawal from opioids usually develops how many hours after delivery?
24-72h after delivery
but symptoms can be delayed for up to 14 days, so monitoring may be required for several weeks
Signs of neonatal withdrawal from opioids usually develop 24–72 hours after delivery but monitoring may be required for several weeks because
symptoms may be delayed for up to 14 days
symptoms of neonatal withdrawal from opioids (+ severe but rare symptoms)
high-pitched cry, rapid breathing, hungry but ineffective suckling, and excessive wakefulness
severe, but rare symptoms include hypertonicity and convulsions.
a patient well known to you comes into the pharmacy. she has recently given birth. she says that her baby has a very high pitched cry, is breathing very quickly, and is staying awake a lot. you know she is opioid maintenance therapy, so you suspect that the baby has…
signs of neonatal withdrawal from opioids
opioid substitution during BF - doses
Doses of methadone and buprenorphine should be kept as low as possible in breast-feeding mothers
what are the symptoms in breast fed babies of mothers taking opioid substitutes that need to be reported urgently to HCP? (3)
increased sleepiness
breathing difficulties
limpness
