Adverse drug reactions anaphylactoid

Johnson TM +, J Am Acad Dermatol 17(2 Pt I), 192 Anaphylactoid reactions/Anaphylaxis (I 992) Breathnach SM +, Adverse Drug Reactions and the Skin Blackwell, Oxford, 193 (passim)... 

Optic neuritis (a decrease in visual acuity and changes in color perception), which appears to be related to the dose given and die duration of treatment, has occurred in some patients receiving ethambutol. Usually, tiiis adverse reaction disappears when the drug is discontinued. Other adverse reactions are dermatitis, pruritus, anaphylactoid reactions (unusual or exaggerated allergic reactions), joint pain, anorexia, nausea, and vomiting. 

These are adverse reactions resembling the effects of histamine liberation Chistaminoid ) and unrelated to the mode of action of the drug itself. Histamine release appears to be the main factor involved in all types of hypersensitivity reactions and its release explains most of the manifestations. The term anaphylactoid may equally be used to describe these reactions, meaning simply that they resemble anaphylactic reactions, while the term anaphylactic is used specifically for immune-mediated phenomena involving previous sensitisation of the patient. It is often difficult to determine the true nature and cause of the reaction. 

Adverse reactions to iodine (iodism) are uncommon and in most cases reversible upon discontinuance. They include acneiform rash (similar to that of bromism), swollen salivary glands, mucous membrane ulcerations, conjunctivitis, rhinorrhea, drug fever, metallic taste, bleeding disorders and, rarely, anaphylactoid reactions. 

The main systems affected by adverse effects of the quinolones are the skin, liver, and nervous system. The best-known adverse effect is phototoxicity, the risk of which varies markedly among the quinolones lomefloxacin and sparfloxacin carry a particularly high risk. The development of phototoxicity is based on an interaction between hght and the drug. Neurotoxicity also occurs, with marked variation of incidence between the various compounds. Hypersensitivity reactions to quinolones are rare, and include anaphylactic shock and anaphylactoid reactions. Organ-specific reactions attributed to hypersensitivity involve the liver and kidneys. If hypersensitivity reactions occur, switching from one qui-nolone compound to another is probably not advisable, since there is cross-reactivity. 

Anaphylactic shock associated with cinoxacin was reported in three patients by the Netherlands Center for Monitoring of Adverse Reactions to Drugs (97). Another 17 cases were reported to the WHO Collaborating Center for International Drug Monitoring. In some cases the reaction was observed immediately after the first dose of a repeat cycle of treatment. Anaphylactoid reactions to ciprofloxacin have been reported in patients with cystic fibrosis (98-100). 

NAC functions by detoxifying NAPQI. It both repletes GSH stores and may conjugate directly with NAPQI by serving as a GSH substitute. Even in the presence of activated charcoal, there is ample absorption of NAC, and neither should activated charcoal be avoided nor NAC administration be delayed because of concerns of a charcoal-NAC interaction. Adverse reactions to NAC include rash (including urticaria, which does not require drug discontinuation), nausea, vomiting, diarrhea, and rare anaphylactoid reactions. 

Vancomycin is highly associated with adverse infusion-related events. These are especially prevalent with higher doses and a rapid infusion rate. A rapid infusion rate has been shown to cause anaphylactoid reactions, including hypotension, wheezing, dyspnea, urticaria, and pruritus. A significant drug rash (the so-called red man syndrome) also can occur. These events are much less frequent with a slower infusion rate. 

Lorenz W, Doenicke A (1978) Anaphylactoid reactions and histamine release by intravenous drugs used in surgery and anaesthesia. In Watkins J, Ward AM (eds) Adverse response to intravenous drugs. Academic Press, London Grune Stratton, New York, pp 83-112... 

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