Allergic Rash Due to Antiepileptic Drugs: Clinical Features and Management

Abstract

Optimal management of allergic rash from antiepileptic drugs (AEDs) is unclear. We identified 50 patients with 68 reactions (36 to one AED, 10 to two AEDs, and four to three AEDs). The AEDs implicated were carbamazepine, 30; phenobarbital (PB), 20; phenytoin, 16; ethosuximide, one; and AED combination, one. Sixty-three reactions were cutaneous eruptions, three exfoliative dermatitis, and two Stevens-Johnson syndrome. Forty-six reactions were mild (rash only), 18 moderate (systemic symptoms or other organ system involvement), and four life-threatening (all with PB). In most patients with greater than 1 reaction, the second and third reactions were not more severe than the first. Prior antibiotic allergies or nonmedication allergies were no more common than in a control group without reactions. The AED was ceased abruptly in 59 patients (22 of whom did not receive a new AED), tapered in five, and continued unchanged in four. Despite this, there was no status epilepticus (SE) during the reaction or its treatment, and no patient's seizure control deteriorated. In 40 cases, a new AED was added--16 after the reaction had resolved and 24 before total resolution. Rash recurred with the new AED in 50 and 42% respectively (NS). We conclude that, though allergic rashes to AEDs are usually mild, the rare occurrence of severe reactions indicates that the AED should be ceased. This can be done abruptly with minimal risk of SE. A new AED can be added, if necessary, prior to the resolution of the rash without increasing the risk of further reactions.

Carbamazepine-Induced Hypersensitivity Syndrome in a Child with Epilepsy

“…allopurinol, gold salts, dapsone and non-steroidal anti-inflammatory drugs (13,(16)(17)(18)(19), but the aromatic antiepileptic agents (phenytoin, carbamazepine and phenobarbital) and sulfonamides are the most frequent invol ved drugs (5,(20)(21)(22). A potential cross-reactivity among the three major anticonvulsants which can limit the choices for future therapy in a patient who has had this reaction (23,24).…”

“…Idiosyncratic reactions, including skin problems, have been frequently described and vary from 25% to 50% (5)(6)(7)(8)(9).…”

Cross-sensitivity of skin rashes with antiepileptic drug use

“…[4][5][6][7][8][9][10][11][12][13][14] Few studies have determined the frequency of cross-sensitivity of rash among a large number of patients taking multiple AEDs. [4][5][6][7][8][9][10][11][12][13][14] A recent study from our database investigated predictors of AED-related rash in 1,890 outpatients: for most AEDs, the risk of developing a rash increased three-to fourfold if the patient had a rash to one or more other AEDs, or an allergy (with or without rash) to a non-AED medication. 2 These findings prompted this study to determine the rates of rash crosssensitivity associated with specific pairs of commonly used AEDs.…”

Lamotrigine Hypersensitivity in Childhood Epilepsy

“…PB, CBZ, and PHT may produce widespread hypersensitivity reaction, and management of affected patients can be complicated by the potential cross-reactivity to these AEDs because of the similar aromatic ring in their structure (7,8,(15)(16)(17). With regard to new AEDs, the percentage of LTGtreated patients with epilepsy who are reported to have developed adverse skin reactions ranges greatly, from 3 to 16.5% (3,4).…”