An opioid taper can be considered as the first step in assessing opioid dependence when use has been in lower doses or over shorter periods, and other pharmacological approaches are not indicated. For an opioid taper to be indicated, the patient should describe a pattern of daily or near daily codeine use for at least a month (it is likely it would be longer) and opioid withdrawal symptoms on codeine cessation (see Box 2). If the patient has not experienced opioid withdrawal symptoms on cessation then it is appropriate, before a medication-assisted taper is considered, to educate them about withdrawal symptoms and ask them to try ceasing codeine and record daily symptoms in a symptom diary.
Symptomatic medications (nonopioid medications that reduce the symptoms of opioid withdrawal) can be used by patients who wish to self-manage codeine cessation without an opioid being prescribed. Examples are listed in Table 1. Patients should be advised that these medications can reduce the discomfort but may not entirely relieve opioid withdrawal symptoms.
Medication options for managing codeine withdrawal symptoms
A range of medications have been proposed to help manage the temporary discomfort caused by codeine cessation, including the nonopioid symptomatic medications described above and opioids. These medications and their regulatory requirements, supporting evidence, advantages and disadvantages are summarised in Table 2.8-16 This use is off-label for most; many have limited supporting evidence and not all can be recommended.
The largest body of evidence supports the use of sublingual buprenorphine (provided as buprenorphine–naloxone), followed by symptomatic medications. The latter nonopioid medications are an alternative that may be appropriate for patients with lower-level opioid neuroadaptation and are discussed above. Prescribed codeine, tramadol and buprenorphine patches have also been proposed to treat opioid withdrawal but their use is off label for this purpose and they have a limited evidence base. Tramadol and buprenorphine patches are indicated only to treat pain.
If opioid withdrawal symptoms are not relieved by buprenorphine or symptomatic medications then this may indicate a higher level of dependence. Where the treating doctor does not possess relevant training and experience, these patients may require referral for management by an addiction medicine specialist in an inpatient or outpatient setting. Maintenance treatment with opioid agonists (buprenorphine–naloxone or methadone) should be considered for these patients.
Prescribing of opioids for the management of codeine withdrawal should be limited to a maximum of seven to 10 days. If longer periods of medication are required then these should be provided in the context of medication-assisted treatment for opioid dependence (buprenorphine–naloxone or methadone) in accordance with national and jurisdictional guidelines.5 There is little evidence to support the use of medications other than methadone and buprenorphine–naloxone, and for this reason these other approaches are not recommended. It is strongly recommended not to transfer patients to strong opioids such as oxycodone, oxycodone–naloxone or fentanyl.
Patients should be in contact with an experienced healthcare professional while undergoing opioid withdrawal, and this contact should be at least daily during the first few days to allow clinical review and dose adjustment. Because of interpatient variability in the opioid effects of codeine, the risk of either undertreatment or oversedation should be considered. Review of patients is recommended a few hours after the first dose of buprenorphine–naloxone. Patients should be warned that they may have difficulty fulfilling their usual roles during this time; they may need time off work or to make alternative child care arrangements and they may not be able to drive a car (depending on the strength of the medication prescribed and how it affects them). If necessary, opioid withdrawal can be conducted in a residential facility such as a drug and alcohol detoxification service.
Buprenorphine in management of codeine withdrawal
The largest body of evidence is for the use of buprenorphine in the clinical management of opioid withdrawal.16 The efficacy of buprenorphine is supported by a Cochrane review, and the most clinical experience exists for buprenorphine to treat codeine dependence.16,17
Buprenorphine is ideal for management of opioid withdrawal as it is a partial agonist with a ceiling on respiratory depressant effects and can be administered with once-daily supervised dosing.18 A sample buprenorphine–naloxone withdrawal regimen is shown in Box 8.
When a patient commences buprenorphine, key considerations include avoiding ‘precipitated withdrawal’. This occurs when buprenorphine is administered while a full opioid agonist is still active in the body. Buprenorphine displaces the full opioid agonist at the mu-opioid receptor, leading to opioid withdrawal symptoms. To avoid precipitating opioid withdrawal, standard procedures outlined in guidelines include waiting until mild-to-moderate opioid withdrawal symptoms are observable, typically about 12 hours after the last dose of a short-acting opioid such as codeine. The Clinical Opioid Withdrawal Scale is a useful tool to assess opioid withdrawal (Box 9).19
GPs unfamiliar with their local state and territory requirements on prescribing buprenorphine should contact their local health department or addiction specialists for advice and support (see Box 10 for contact details). Advice is also available from local drug and alcohol services, which in most states provide 24-hour telephone advice lines (Box 10). Before buprenorphine treatment begins, an authority is required from the state or territory health department. In states such as Victoria, South Australia and Western Australia, GPs can commence buprenorphine–naloxone treatment without being accredited prescribers or with minimal additional training. However, most other jurisdictions require doctors to undergo some training before being authorised to prescribe buprenorphine. Buprenorphine (usually as buprenorphine–naloxone) is dispensed only by specific pharmacies. The pharmacy should be contacted in advance to confirm that it can accept the patient.