Before deciding to initiate treatment, patients of Han Chinese and Thai origin should whenever possible be screened for HLA-B*1502 as this allele strongly predicts the risk of severe carbamazepine-associated Stevens-Johnson syndrome (See information on genetic testings and cutaneous reactions in section 4.4).

Epilepsy:

The dose of carbamazepine should be adjusted to the needs of the individual patient to achieve adequate control of seizures. Determination of plasma levels may help in establishing the optimum dosage. In the treatment of epilepsy, the dose of carbamazepine usually requires total plasma-carbamazepine concentrations of about 4 to 12 micrograms/mL (17 to 50 micromoles/litre) (see warnings and precautions).

Adults, Elderly, Children and Adolescents: 125mg and 250mg suppositories are available for short-term use as replacement therapy (maximum period recommended: 7 days) in patients for whom oral treatment is temporarily not possible, for example in post-operative or unconscious subjects.

When switching from oral formulations to suppositories the dosage should be increased by approximately 25% (the 125 and 250mg suppositories correspond to 100 and 200mg tablets respectively). Tegretol Suppositories have been shown to provide plasma levels which are well within the therapeutic range (see Pharmacokinetics).

Where Suppositories are used the maximum daily dose is limited to 1000mg (250mg qid at 6 hour intervals, see Pharmacokinetics).

No clinical data are available on the use of suppositories in indications other than epilepsy.

Due to the potential for drug interactions, the dosage of Tegretol should be selected with caution