Opioid dependence

Question 1

1) Untreated heroin dependence shows early withdrawal symptoms within how many hours?
2) symptoms subside substantially after how many days?

Answer 1

1) within 8 hours, with peak symptoms at 36–72 hours

2) symptoms subside substantially after 5 days

Question 2

which 2 drugs are used as substitution therapy in opioid dependence?

Answer 2

Methadone and buprenorphine

Question 3

there are 2 types of regimes once a patient is stable on therapy. Explain the benefits of maintenance treatment and outline what needs to be monitored

Answer 3

1) enables patients to achieve stability, reduces drug use and crime, and improves health
2) Regularly reviewed to ensure benefit. Monitor for signs of toxicity, and the patient should be told to be aware of warning signs of toxicity on initiation and during titration

Question 4

A withdrawal regimen after stabilisation with methadone or buprenorphine should be considered. Explain why enforced withdrawal is ineffective

Answer 4

It increases the risk of patients relapsing and subsequently overdosing because of loss of tolerance

Question 5

Complete withdrawal from opioids usually takes up to how many weeks in the following:

1) Inpatient or residential setting
2) community setting

Answer 5

1) Up to 4 weeks in an inpatient or residential setting

2) Up to 12 weeks in a community setting

Question 6

if the patient cannot tolerate withdrawal what should then be started?

Answer 6

withdrawal regimen should be stopped and maintenance therapy should be resumed at the optimal dose

Question 7

Following successful withdrawal treatment what should be provided to patients and for how long?

Answer 7

1) Further support and monitoring to maintain abstinence

2) for a period of at least 6 months

Question 8

how many days of regular prescribed opioid maintenance therapy can be missed before patients loose tolerance. How should this be managed?

Answer 8

1) Miss 3 days or more of their regular prescribed doses. These patients are at risk of overdose because of loss of tolerance
2) Consider reducing the dose in these patients

Question 9

if a patient misses 5 or more days of treatment, how should this be managed?

Answer 9

1) An assessment of illicit drug use is also recommended before restarting substitution therapy
2) particularly important for patients taking buprenorphine due to risk of precipitated withdrawal

Question 10

explain the benefits of buprenorphine compared to methadone treatment

Answer 10

1) less sedating than methadone- more suitable for employed patients or those undertaking other skilled tasks such as driving
2) safer than methadone when used in conjunction with other sedating drugs, and has fewer drug interactions
3) Dose reductions easier as withdrawal symptoms are milder, and patients generally require fewer adjunctive medications
4) lower risk of overdose
5) can be given on alternate days in higher doses and requires a shorter drug-free period before induction with naltrexone

Question 11

Naltrexone is an opioid-receptor antagonist, what is it indicated for?

Answer 11

Adjunct to prevent relapse in formerly opioid-dependent patients (who have remained opioid-free for at least 7–10 days)

Question 12

Patients dependent on high doses of opioids may be at increased risk of precipitated withdrawal. when can precipitated withdrawal occur in patients?

Answer 12

1) if buprenorphine is administered when other opioid agonist drugs are in circulation. Precipitated opioid withdrawal, if it occurs,
2) starts within 1-3 hours of the first buprenorphine dose and peaks at around 6 hours

Question 13

what adjunctive therapy can be given to patients who have severe symptoms of precipitated withdrawal?

Answer 13

Non-opioid adjunctive therapy, such as lofexidine

Question 14

what can be prescribed for patients when there is a risk of dose diversion for parenteral administration?

Answer 14

1) combination preparation of buprenorphine with naloxone (Suboxone®).
2) Naloxone precipitates withdrawal if the preparation is injected, but it has little effect when the preparation is taken sublingually

Question 15

Methadone is a long-acting opioid agonist, that is usually administered in a single daily dose. Which patients might prefer methadone over buprenorphine because of its more pronounced sedative effect

Answer 15

Prefer methadone to buprenorphine because:

1) long history of opioid misuse
2) typically abuse a variety of sedative drugs/alcohol
3) Experience increased anxiety during withdrawal

Question 16

1) how long after the last heroin dose is methadone initiated?
2) what might be considered on the first day if there is evidence of persistent opioid withdrawal symptoms?

Answer 16

1) at least 8 hours after the last heroin dose- if there is objective evidence of withdrawal symptoms
2) A supplementary dose on the first day may be considered if there is evidence of persistent opioid withdrawal symptoms

Question 17

Why does titration to the optimal dose in methadone maintenance treatment may take several weeks, and what are the problems associated with this?

Answer 17

Methadone has a long plasma-half life. A dose tolerated on the first day of treatment may become a toxic dose on the third day as cumulative toxicity develops

Question 18

Explain why opioid substitution therapy is recommended during pregnancy?

Answer 18

1) Acute withdrawal of opioids can cause fetal death

2) It carries a lower risk to the fetus than continued use of illicit drugs

Question 19

If a woman who is stabilised on methadone or buprenorphine becomes pregnant, therapy should be continued. Many pregnant patients choose a withdrawal regimen, but why should this not be recommended?

Answer 19

1) Withdrawal during the first trimester should be avoided due to increased risk of spontaneous miscarriage
2) withdrawal in the third trimester is not recommended because maternal withdrawal, is associated with fetal distress, stillbirth, and the risk of neonatal mortality.

Question 20

If methadone or buprenorphine are to be withdraw, when should this be done in pregnancy and how often should the dose should be reduced?

Answer 20

1) undertaken gradually during the second trimester, with dose reductions made every 3–5 days.
↳ If illicit drug use occurs, re-estabilish on maintenance dose and consider stopping the withdrawal

Question 21

Drug metabolism can be increased in the third trimester in those taking substitution therapy. How should this be managed?

Answer 21

Either increase the dose of methadone or change to twice-daily consumption (or a combination of both strategies) to prevent withdrawal symptoms from developing

Question 22

If the mother is prescribed high doses of opioid substitute, what should be monitored in neonates?

Answer 22

monitored for respiratory depression and signs of withdrawal

Question 23

Signs of neonatal withdrawal from opioids develop within how many hours after delivery?

Answer 23

Develop 24–72 hours after delivery but symptoms may be delayed for up to 14 days, so monitoring may be required for several weeks

Question 24

what are the signs and symptoms of neonatal withdrawal?

Answer 24

1) High-pitched cry
2) Rapid breathing
3) Hungry but ineffective suckling
4) Excessive wakefulness
5) Severe, but rare symptoms include hypertonicity and convulsions

Question 25

Doses of methadone and buprenorphine should be kept as low as possible in breast-feeding mothers. What symptoms in breast-fed babies should be reported urgently to a healthcare professional ?

Answer 25

Increased sleepiness, breathing difficulties, or limpness

Question 26

Adjunctive therapy may be required for the management of opioid withdrawal symptoms. what medication would be prescribed for the following:

1) Control of diarrhoea
2) Stomach cramps
3) Muscular pains and headaches
4) nausea or vomiting:
5) Insomnia

Answer 26

1) Control of diarrhoea: loperamide
2) Stomach cramps: Mebeverine
3) Muscular pains and headaches: paracetamol/ NSAIDs
↳Topical rubefacients helpful for relieving muscle pain associated with methadone withdrawal.
4) Nausea or vomiting: Metoclopramide / prochlorperazine
5) Insomnia: short-acting benzodiazepines or zopiclone may be prescribed-short course of a few days only

Question 27

which drug might alleviate some of the physical symptoms of opioid withdrawal?

Answer 27

Lofexidine by attenuating the increase in adrenergic neurotransmission that occurs during opioid withdrawal.

Question 28

when might lofexidine be prescribed instead of an opioid substitute?

Answer 28

in patients who have mild or uncertain dependence (including young people), and those with a short history of illicit drug use.

Question 29

1) Patients dependant on opioids can be given a supply of which drug in case of an accidental overdose.
2) which drug can be prescribed to prevent relapse?

Answer 29

1) Naloxone
2) Naltrexone - prescribed as an aid to prevent relapse in formerly opioid-dependent patients
↳(both of these drugs are opioid-receptor antagonists)

Question 30

explain why opioid so substitution therapy is usually inappropriate in children

Answer 30

The harmful effects of drug misuse are more often related to acute intoxication than to dependence