Cephalosporins allergic reactions

The cephalosporins generally cause few side effects (80,132,219—221). Thrombophlebitis occurs as a result of intravenous administration of all cephalosporins. Hypersensitivity reactions related to the cephalosporins are the most common side effects observed, but these are less common than found with the penicillins. Clinically only about 5—10% of patients with allergic reactions to the penicillins manifest the same reactions to the cephalosporins, and data would contradict any tme cross-reactivity to cephalosporins in patients who have previously reacted to penicillin (80,132,219). 

The most common adverse reactions seen with administration of the cephalosporins are gastrointestinal disturbances, such as nausea, vomiting, and diarrhea Hypersensitivity (allergic) reactions may occur with administration of the cephalosporins and range from mild to life threatening. Mild hypersensitivity reactions include pruritus, urticaria, and skin rashes. More serious hypersensitivity reactions include S teveils-Johnson syndrome (fever, cough, muscular aches and... 

Some types of allergic reaction, for example immediate or delayed-type skin allergies, serum-sickness-like reactions and anaphylactic reactions, may occur in a proportion of patients given penicillin treatment. There is some, but not complete, cross-allergy with cephalosporins. 

Cephalosporin Ceftiofur and cephapirin Gastrointestinal upset, diarrhea, nausea and allergic reactions... 

In penicillin-allergic patients, oral or parenteral clindamycin may be used. Alternatively, a first-generation cephalosporin such as cefazolin (1 to 2 g IV every 6 to 8 hours) may be used cautiously for patients who have not experienced immediate or anaphylactic penicillin reactions and are penicillin skin test negative. In severe cases in which cephalosporins cannot be used because of documented methicillin resistance or severe allergic reactions to /1-lactam antibiotics, IV vancomycin should be administered. 

Hypersensitivity reactions Make careful inquiry for a history of hypersensitivity reactions. Monitor patients who have had immediate hypersensitivity reactions to penicillins or cephalosporins. If an allergic reaction occurs, discontinue the drug and institute supportive treatment. Cross-sensitivity with other penicillins or -lactam antibiotics is rare. 

Cephalosporins are generally well tolerated and various side effects include pain at the site of injection and can also cause thrombophlebitis. Allergic reactions include skin rash, fever, serum sickness, eosino-philia, neutropenia and rarely anaphylactic reaction. 

In some patients, cephalosporins may cause an allergic reaction similar to the penicillin hypersensitivity described previously. A cross-sensitivity often exists a patient who is allergic to penicillin drugs will also display hypersensitivity to cephalosporin agents. Other principal adverse effects of cephalosporins include gastrointestinal problems such as stomach cramps, diarrhea, nausea, and vomiting. 

Allergic manifestations The cephalosporins should be avoided or used with caution in individuals allergic to penicillins (about 5 to 15% show cross-sensitivity). In contrast, the incidence of allergic reactions to cephalosporins is 1-2% in patients without a history of allergy to penicillins. 

Correct choice = E. Unlike the penicillins, cephalosporins are less sensitive to p-lactamase activity. Inflammation does increase penetration of penicillin into the CSF. All penicillin derivatives, including penicillin V, can potentially trigger an allergic reaction in patients sensitive to penicillin G. Cefoxitin can often be used in these patients. However, caution should be exercised, since there is about 5 to 15% crossreactivity. 

Neither in vitro tests nor skin tests reliably predict cephalosporin allergy (166). The true frequency of allergic reactions in penicillin-allergic patients exposed to cephalosporins has been estimated to be 1 or 2% (167). Nevertheless, when there is a history of penicillin anaphylaxis or other severe IgE-mediated reactions, it is wise to avoid cephalosporins. 

De Week AL. Penicillins and cephalosporins. In Allergic Reactions to Drugs. Heidelberg Springer-Verlag, 1983 423. 

Relative contraindications to sulfonamides are systemic lupus erythematosus and a known predisposition to lupuslike reactions. Allergic reactions to antimicrobials are frequent in patients with Sjogren s sjmdrome. They are especially susceptible to reactions to penidUins, cephalosporins, and sulfonamides, but reactions to macrohdes and tetracyclines also seem to be over-represented in these patients (210). 

Note Penicillin and cephalosporins share a common beta-lactam structure. People who are allergic to penicillin are approximately 4 times more likely to develop an allergic reaction to a cephalosporin than those people who have no penicillin allergy. (From 5 to 16% of patients allergic to penicillin develop reactions to cephalosporins)... 

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