• These are usually only tried when non-opioid analgesics have been tried and have not been fully effective
• Always co-prescribe a regular laxative: opioids usually cause constipation and it is better to prevent this from the outset

Other side effects which should be anticipated and promptly managed are:

• Nausea and vomiting: normally settles within 5-7 days, but if treatment is required, use cyclizine first-line.
• Pruritus: maintain skin hydration carefully; topical agents such as Eurax may be helpful; systemic agents such as ondansetron may be worth trying. Opioid switch is another option - less pruritogenic opioids are hydromorphone and oxycodone. Chlorpheniramine or other non-sedating anti-histamine may be helpful
• Urinary retention: occasionally catheterization may be required. Check that constipation is not a contributory factor. Carbachol or Bethanecol may also help. Could also consider reducing opioid dose or switching to an alternative opioid
• Respiratory depression: is very very rare, and can be avoided with steady dose titration. Naloxone will reverse respiratory depression at the cost of analgesic effect, and should be used with caution as it can also cause rebound agitation
• Drowsiness: usually wears off after 3-5 days
• Nightmares are occasionally reported. These may settle with time, but if troublesome opioid switch may be helpful or the addition of Haloperidol may be of benefit.
• Physical dependence: is not usually a problem in this setting, but if planning to stop opiates always do it slowly to avoid the unwanted effects of withdrawal
• Tolerance: may occur as opiates are often used over prolonged periods. Doses should be titrated up carefully in the usual fashion, or if side effects preclude this, opioid switch should be considered.

Dihydrocodeine tartrate

Form

Tablet: 30mg, 40mg
Liquid: 10mg in 5mL Injection: 50mg in 1mL

Dose (oral /deep SC)

1-4yr: 500µg/kg 4-6hr
4-12yr: 500µg-1mg/kg 4-6hr (max: 30mg/dose)
>12yr: 30-50mg 4-6hr

Weak Opiates have been removed from the WHO ladder and are only used for acute and post-operative pain setting. Codeine has been removed from this book since it is contraindicated in the under 12year age group. Cautions and contraindications and warnings: avoid or reduce dose in moderate/severe renal failure, chronic liver disease and hypothyroidism. Avoid in respiratory depression, cystic fibrosis, head injury and raised intracranial pressure.

Licence: Licensed for children >4yrs