Hypersensitivity reactions penicillin

Penicillins, which are the safest of antibiotics, produce few direct toxic reactions, and most of the serious side effects are hypersensitivity reactions. Penicillins and their by-products, penicilloic acid and penicilloyl polylysine, are antigenic in susceptible individuals who develop immunoglobulin G... 

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). 

As is well known, the principal toxicity associated with penicillin therapy is the occurrence of hypersensitivity reactions. This and other aspects of pencillin toxicity have been recently reviewed 81MI51106). 

As with all drugs, the specific side effects of the quinolones must be considered when they are chosen for treatment of bacterial infections [5]. Reactions of the gastrointestinal tract and the central neivous system are the most often observed adverse effects during therapy with quinolones. It should be underlined, however, that compared with many other antimicrobials, diarrhea is less frequently observed during quinolone treatment. Antibiotic-associated colitis has been observed rarely during quinolone therapy. Similarly, hypersensitivity reactions, as observed during therapy with penicillins and other (3-lactams, is less frequently caused by quinolones. Some other risks of quinolone therapy have been defined and must be considered if a drug from this class is chosen for treatment of bacterial infections. 

A hypersensitivity (or allergic) reaction to a drug occurs in some individuals, especially those with a history of allergy to many substances. Signs and symptoms of a hypersensitivity to penicillin are highlighted in Display 7-3. 

The nurse should observe the patient closely for a hypersensitivity reaction, which may occur any time during therapy with the penicillins If it should occur, it is important to contact the primary health care provider immediately and withhold the drug until the patient is seen by the primary health care provider. 

Hypersensitivity reactions with P-lactam antibiotics, especially penicillin, may encompass any of the type I through IV Gell-Coombs classifications. The most common reactions are maculopapular and urticarial eruptions.7 While rare (less than 0.05%), anaphylaxis to penicillins causes the greatest concern because they are responsible for the majority of drug-induced anaphylaxis deaths in patients, accounting for 75% of all ana-i phylaxis cases in the United States.5,8 The treatment of ana-I phylaxis is given in Table 51-2.9... 

The answers are 25-e, 26-b, 27-a. (Hardmanr pp 67—68. Katzung, pp 30, 134.) Anaphylaxis refers to an acute hypersensitivity reaction that appears to be mediated primarily by immunoglobulin E (IgE). Specific antigens can interact with these antibodies and cause sensitized mast cells to release vasoactive substances, such as histamine. Anaphylaxis to penicillin is one of the best-known examples the drug of choice to relieve the symptoms is epinephrine. 

The answer is a. (Hardman, pp 1084-1085J Amoxicillin is classified as an aminopenicillin along with ampicillin. Because it is less affected than ampicillin by the presence of food, it has a superior absorption in the GI tract. It is sensitive to penicillinase and has a narrow spectrum of activity toward certain Gram-positive and Gram-negative organisms, but not Pseudomonas. Because it is in the penicillin family, hypersensitivity reactions are a possibility... 

Generally reserved for patients with hypersensitivity reactions to penicillin. 

Vancomycin is effective and is the drug of choice for the patient with a history of immediate-type hypersensitivity reaction to penicillin. When vancomycin is used, the addition of gentamicin is not recommended. 

If a patient has a mild, delayed allergy to penicillin, first-generation cephalosporins are effective alternatives but should be avoided in patients with an immediate-type hypersensitivity reaction. 

Penicillin G 24 million units/24 h IV in four to six equally divided doses may be used in place of nafcillin or oxacillin if strain is penicillin susceptible (minimum inhibitory concentration 0,1 mcg/mL) and does not produce /5-lactamase vancomycin should be used in patients with immediate-type hypersensitivity reactions to beta-lactam antibiotics (see Table 37-3 for dosing guidelines) cefazolin may be substituted for nafcillin or oxacillin in patients with non-immediate-type hypersensitivity reactions to penicillins... 

Weiss, M.E. and Adkinson, N.F., Immediate hypersensitivity reactions to penicillin and related antibiotics, Clin. Allergy, 18, 515, 1988. 

Hypersensitivity reactions Serious and occasionally fatal immediate-hypersensitivity reactions have occurred. The incidence of anaphylactic shock is between 0.015% and 0.04%. Anaphylactic shock resulting in death has occurred in approximately 0.002% of the patients treated. These reactions are likely to be immediate and severe in penicillin-sensitive individuals with a history of atopic conditions. 

Hematologic/Lymphatic Anemia hemolytic anemia thrombocytopenia thrombocytopenic purpura eosinophilia leukopenia granulocytopenia neutropenia bone marrow depression agranulocytosis reduction of hemoglobin or hematocrit prolongation of bleeding and prothrombin time decrease in WBC and lymphocyte counts increase in lymphocytes, monocytes, basophils, and platelets. Hypersensitivity Adverse reactions (estimated incidence, 1% to 10%) are more likely to occur in individuals with previously demonstrated hypersensitivity. In penicillin-sensitive individuals with a history of allergy, asthma, or hay fever, the reactions may be immediate and severe. 

Hypersensitivity reactions Reactions range from mild to life-threatening. Before therapy is instituted, inquire about previous hypersensitivity reactions to cephalosporins and penicillins. 

There have been reports of individuals with a history of penicillin hypersensitivity who have experienced severe hypersensitivity reactions when treated with other -lactams. 

Hypersensitivity reactions Serious and occasionally fatal hypersensitivity reactions have occurred in patients receiving therapy with -lactams. They are more apt to occur in people with a history of sensitivity to multiple allergens. Patients with a history of penicillin hypersensitivity have experienced severe reactions when treated with another -lactam. 

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. 

Patients with a history of allergies, especially to penicillin, are at increased risk for developing a severe hypersensitivity reaction, marked by severe pruritus, angio-edema, bronchospasm, and anaphylaxis. 

Nephrotoxicity may occur, especially in patients with preexisting renal disease. Severe hypersensitivity reaction including severe pruritus, angioedema, broncho-spasm, and anaphylaxis, particularly in patients with a history of allergies, especially to penicillins, may occur. 

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