Risk factors, drug allergy

Fig. 1.2 Patient-related and drug-related risk factors for drug allergies...

Demoly, P. and Rebelo Gomes, E., Drug hypersensitivities definition, epidemiology and risk factors, Eur. Ann. Allergy Clin, Immunol., 37, 202, 2005. 

Imipenem-cilastatin is one of the drugs of first choice for the empirical therapy of many polymicrobial pulmonary, intraabdominal, and soft tissue infections. The notable adverse effect of imipenem-cilastatin is seizures affecting 1% of patients. Risk factors for seizures are old age, head trauma, previous seizure disorder, cerebrovascular accident, and renal failure. Among patients with a history of penicillin allergy, 10% are cross-sensitive to imipenem-cilastatin. 

About 28% of patients develop IgG or IgE antibodies after a single exposure to protamine, but fortunately few develop a catastrophic allergic reaction on subsequent exposure to the drug. Nonetheless, prior exposure does increase the risk for an anaphylactic reaction. Other risk factors are fish allergy and patients with diabetes mellitus treated with neutral protamine Flagedorn (NPFI) insulin. After vasectomy, 22%... 

Adkinson NF. Risk factors for drug allergy. J Allergy Clin Immunol 1984 74 567-72. 

Van Arsdel PP Jr. Classification of risk factors for drug allergy. Immunol Allergy Clin North Am 1991 11 475. 

Increasing age (over 55 years), male sex, and duration of treatment are risk factors (26,32,47), while drug dose and route of administration, other medications, previous drug allergies, or prior use of co-amoxiclav were not significantly associated with the reaction. 

This patient had multiple risk factors for anesthesia-induced hepatitis, including obesity, middle age, female sex, a history of drug allergies, and multiple exposures to fluorinated anesthetic agents. Desflurane has a very low rate of hepatic oxidative metabolism (0.02 versus 20% for halothane), and is considered to be one of the safest volatile agents as far as hepatotoxicity is concerned. Nevertheless, this case shows that it can cause severe hepatotoxicity. 

No specific risk factors have been identified because these are idiosyncratic hypersensitivity reactions. Individuals with other drug allergies may have increased risk and warrant close monitoring. 

Thong, B.Y Tan, T.C. (2011). Epidemiology and risk factors for drug allergy. British Journal of Clinical Pharmacology, 71,... 

Risk factors for a late skin reaction following administration of an iodinated contrast medium include current and up to 2 years past treatment with interleukin-2 (IL-2), a history of drug allergy or contact hypersensitivity, and a history of reaction to a previous contrast medium. Late reactions are more conunon in patients who reacted previously, especially if the same contrast medium is administered (see below). The latter fact is interesting since it suggests that the mechanism of the late reaction with its demonstration of memory may be immunologically and, in particular, T cell mediated. 

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