Carbamazepine

Question 1

indications - epilepsy

Answer 1

focal and secondary generalised tonic clonic seizures
primary generalised tonic clonic seizures

Question 2

indications - neuropathy

Answer 2

trigeminal neuralgia (pain in face)
diabetic neuropathy

Question 3

indications - mental health

Answer 3

prophylaxis bipolar disorder unresponsive to lithium

Question 4

indications - substance misuse

Answer 4

adjunct in acute alcohol withdrawal

Question 5

3 CIs

Answer 5

Acute porphyrias; AV conduction abnormalities (unless paced); history of bone-marrow depression

Question 6

vitamin D supplementation

Answer 6

MHRA advises consider vitamin D supplementation in patients who are immobilised for long periods or who have inadequate sun exposure or dietary intake of calcium.

Question 7

withdraw immediately if (hint liver and blood)

Answer 7

Carbamazepine should be withdrawn immediately in cases of aggravated liver dysfunction or acute liver disease.

Leucopenia that is severe, progressive, or associated with clinical symptoms requires withdrawal (if necessary under cover of a suitable alternative).

Question 8

skin disorder and HLA allele

Answer 8

The presence of HLA-B*1502 allele, particularly in individuals of Han Chinese or Thai origin, is strongly associated with an increased risk of Stevens-Johnson syndrome

The presence of HLA-A*3101 allele, particularly in individuals of European or Japanese origin, is associated with an increased risk of cutaneous adverse reactions but there are insufficient data to support pre-treatment screening. Consider use if potential benefit outweighs risk.

Question 9

Seizure exacerbation - which types

Answer 9

Carbamazepine may exacerbate seizures in patients with absence or myoclonic seizures (including juvenile myoclonic epilepsy), tonic or atonic seizures, Dravet syndrome, Lennox-Gastaut syndrome, and myoclonic-atonic seizures.

Question 10

enzyme inhibitor or inducer?

Answer 10

CRAP GPS

inducer which means it decreases the level of other drugs!

Question 11

miconazole and carbamazepine interaction severe

Answer 11

Miconazole increases the risk of Carbamazepine toxicity when given with Carbamazepine. Manufacturer advises monitor and adjust dose.

Question 12

interaction with MAOIs

Answer 12

Carbamazepine is predicted to increase the risk of severe toxic reaction when given with Phenelzine. Manufacturer advises avoid and for 14 days after stopping the MAOI.

Question 13

Interaction with DOACs e.g. apixaban, rivaroxaban

Answer 13

Carbamazepine is predicted to decrease the exposure to Rivaroxaban. Manufacturer advises avoid unless patient can be monitored for signs of thrombosis.

Question 14

Carbamazepine and Ulipristal (EHC Ellaone)

Answer 14

Carbamazepine decreases the efficacy of Ulipristal. Manufacturer advises avoid and for 4 weeks after stopping the enzyme inducing drug.

Question 15

Interaction with CHC

Answer 15

Carbamazepine is predicted to decrease the efficacy of Combined hormonal contraceptives

Question 16

Antiepileptic hypersensitivity syndrome associated with carbamazepine?

Answer 16

Yes

Question 17

monitoring in pregnancy

Answer 17

Plasma-drug concentration should be monitored and may be maintained on the lower side of the therapeutic range provided seizure control is maintained.

Question 18

Pre treatment screening - HLA allele

Answer 18

Test for HLA-B*1502 allele in individuals of Han Chinese or Thai origin, and consider testing in other at-risk Asian populations such as individuals of Filipino or Malaysian origin (avoid unless no alternative).

Question 19

Therapeutic drug monitoring

Answer 19

Plasma concentration for optimum response 4–12 mg/litre (20–50 micromol/litre) measured after 1–2 weeks.

Question 20

When to monitor levels of carbamazepine

Answer 20

after 1–2 weeks.

Question 21

monitoring pt parameters

Answer 21

Manufacturer recommends blood counts and hepatic and renal function tests (but evidence of practical value uncertain).

Question 22

treatment cessation for bipolar disorder

Answer 22

reduce the dose gradually over a period of at least 4 weeks.

Question 23

pt and carer advice - Blood, hepatic, or skin disorders

Answer 23

Patients or their carers should be told how to recognise signs of blood, liver, or skin disorders, and advised to seek immediate medical attention if symptoms such as fever, rash, mouth ulcers, bruising, or bleeding develop.