infectious diseases
Penicillins
Adverse Effects of Penicillins
Adverse effects of penicillins include Hypersensitivity reactions, including rashes (most common) Gastrointestinal discomfort including nausea, vomiting, and diarrhea Other adverse effects occur less commonly. Oral penicillin may cause black hairy tongue, which occurs because of irritation of the glossal surface and keratinization of the superficial layers. This is a rare and harmless condition that resolves after the drug is stopped. Most adverse effects are hypersensitivity reactions: Immediate reactions: Anaphylaxis (which can cause death within minutes), urticaria and angioneurotic edema (in 1 to 5/10,000 injections), and death (in about 0.3/10,000 injections) Delayed reactions: Serum sickness, rashes (eg, macular, papular, morbilliform), and exfoliative dermatitis (which usually appears after 7 to 10 days of therapy) Most patients who report an allergic reaction to penicillin do not react to subsequent exposure to penicillin. Although small, risk of an allergic reaction is about 10 times higher for patients who have had a previous allergic reaction. Many patients report adverse reactions to penicillin that are not truly allergic (eg, gastrointestinal adverse effects, nonspecific symptoms). If patients have a vague or inconsistent history of penicillin allergy and taking alternative antibiotics is not effective or convenient, Skin testing may be done. Rashes occur more often withampicillinandamoxicillinthan with other penicillins. Patients with infectious mononucleosis often develop a nonallergic rash, typically maculopapular, usually beginning between days 4 and 7 of treatment. Penicillins can also cause Central nervous system toxicity (eg, seizures) if doses are high, especially in patients with renal insufficiency Nephritis Clostridioides (formerly Clostridium) difficile–Induced Diarrhea (pseudomembranous colitis) Coombs-positive hemolytic anemia Leukopenia Thrombocytopenia Leukopenia seems to occur most often withnafcillin. Any penicillin used in very high IV doses can interfere with platelet function and cause bleeding. Other adverse effects include pain at the IM injection site, thrombophlebitis when the same site is used repeatedly for IV injection, and, with oral formulations, gastrointestinal disturbances. Ticarcillin and carbenicillin in high doses may cause sodium overload, especially in patients with heart or kidney failure, because both are disodium salts. Ticarcillin and carbenicillin can also cause hypokalemic metabolic alkalosis because the large amount of nonabsorbable anion presented to the distal tubules alters H+ ion excretion and secondarily results in potassium loss. 