Support codeine withdrawal
It is generally best to give patients a written plan that weans them gradually off their opioid over seven to 10 days (depending on the daily morphine equivalent). Suitable plans for a patient taking two tablets of paracetamol 500mg plus codeine phosphate 8 mg four times daily are shown in Box 2.
Some patients are unable to tolerate gradual weaning of their opioid, in which case a more abrupt cessation strategy may be helpful. There are some data to suggest this approach may be more effective long term. There may be dual issues of managing withdrawal headache (NSAIDs, metoclopramide) and managing opioid withdrawal symptoms (consider clonidine). Patients on higher doses of codeine may require inpatient management.
If the patient finds (or is likely to find) it difficult to wean off codeine then a bridging strategy can help. Options for bridging therapy include:3
- naproxen 750 to 1000 mg sustained release daily for two to three weeks
- prednisolone for two weeks, at an initial dose of 1mg/kg (maximum 60mg) for three days, then 50mg for three days, then 37.5mg for three days, then 25mg for three days, then 12.5mg for three days, then cease
- unilateral or bilateral greater occipital nerve block.
If outpatient strategies fail then referral for inpatient management of abrupt withdrawal with a lignocaine or ketamine infusion might be appropriate. It might also be appropriate for a psychologist to help with cognitions around pain and acute analgesic use.
Bridging medications should be discontinued after the withdrawal period is successfully navigated. Prophylaxis for gastric ulcers and monitoring of blood sugar level must also be considered.
Prescribe an appropriate acute medication
In patients with migraine or cluster headache, it is worthwhile prescribing an effective triptan for acute treatment. Five triptans are available on the PBS to treat migraine (sumatriptan, zolmitriptan, naratriptan, rizatriptan and eletriptan), and patients may benefit from trying at least two or three to identify the one that is most effective for them.
Prescribe an appropriate preventive medication
At the same time as reducing codeine, it is important to start a preventive medication, if appropriate.5 A preventive should be considered in any patient experiencing more than three to four days of headache per month.
Selecting an appropriate preventive medication depends on diagnosing the underlying headache phenotype. A headache history should be taken, going back to when the headaches first started, as phenotypic features are often clouded by medication overuse. This may mean going back to the patient’s adolescence or even childhood. More detailed information on headache diagnosis and how to select a preventive medication is available in Therapeutic Guidelines: Neurology.7
Primary headache types and specific management
Key features of common primary headache types and suitable preventive medications and acute treatments include the following.
The characteristics of migraine include:
- moderate-to-severe headache lasting four to 72 hours with associated nausea and vomiting, photophobia, phonophobia, osmophobia and motion sensitivity
- can be bilateral or unilateral and can alternate sides
- often described as pulsing or pounding
- affects the ability to undertake normal daily activities
- preceding aura lasting 15 to 30 minutes; this may be visual (most common), other sensory or motor (least common)
- often a family history
- may have known triggers, such as alcohol, foods (e.g. chocolate, strong cheese, monosodium glutamate (MSG), citrus, preserved meats), dehydration, sleep deprivation or excess, hot or stormy weather, menstrual periods, stress or relaxation from stress
- perimenstrual headaches, travel sickness and hangovers after minimal provocation are often clues to a migraine diagnosis.