Table 4

Carbamazepine rectal

Carbamazepine rectal
What is it?Analgesic—acting on neuropathic pain
Mechanism of actionAntiepileptic sodium channel blocker
Starting dose125 mg two times per day
Time to onset of effect4–8 hours17
FormulationSuppository (125 mg rectally is approximately equivalent to 100 mg PO)
IndicationNeuropathic pain
Seizures
Common adverse effectsDizziness; drowsiness; dry mouth; eosinophilia; fatigue; fluid imbalance; gastrointestinal discomfort; headache; hyponatraemia; leucopenia; movement disorders; nausea; oedema; skin reactions; thrombocytopenia; vision disorders; vomiting; weight increased16
ContraindicationsAcute porphyrias; AV conduction abnormalities (unless paced); history of bone marrow depression; cardiac disease; history of haematological reactions to other drugs may exacerbate absence and myoclonic seizures; skin reactions; susceptibility to angle-closure glaucoma16
CautionHepatic impairment
Bone marrow suppression
LicenceLicensed product for seizure control; ‘off label’ for neuropathic pain
BenefitsLicensed product
RisksExpensive
Lack of familiarity with this use in palliative care
Cost£120 for 5×125 mg suppositories
  • AV - atrial ventricular