Allergy
Keith Hopcroft in Instant Wisdom for GPs, 2017
Adverse reactions to drugs can be expected (related to their pharmacological effects) and unexpected. For pharmacological adverse effects, consider dose adjustment or use of an alternative medication. The ‘unexpected’ reactions could be due to allergy, intolerance or idiosyncrasy. An allergic reaction has an immunological basis, although that may not be easy to establish. Hence, for practical purposes, any drug reaction with clinical features of allergy (such as rash or anaphylaxis) can be regarded as allergic. There is usually no simple test to diagnose drug allergy, and drug provocation tests are often required to establish the diagnosis. These are cumbersome and carry significant risk. Therefore, if possible, consideration should be given to using a suitable alternative before referral for drug allergy testing. If no suitable alternative is available, however, patients should be referred for testing and if drug allergy is confirmed, desensitisation is possible, which would allow safe use of the drug.
Critical Appraisal of Animal Models for Antibiotic Toxicity
Adorjan Aszalos in Modern Analysis of Antibiotics, 2020
Predictive tests for drug allergy are usually restricted to evaluating the potential of compounds to induce anaphylaxis and/or delayed hypersensitivity[134]. For anaphylaxis the guinea pig is the species of choice since it is particularly susceptible to anaphylaxis. Additionally, the major shock organin human and guinea pig is the lung. Other species have been utilized for testing for anaphylactic reactions. Specific strains of mice and rats are particularly susceptible, for instance, the hooded lister rat. There are some qualitative differences in the nature of anaphylactic response in humans and guinea pigs that limit the predictive value of this test. For instance, inhumans the major anaphylactic antibody is IgE, which is formed spontaneously. In guinea pigs the usual anaphylactic response involves formation of IgG antibodies. However, IgE antibodies can be induced utilizing special abjuvantsand treatment regimens.
Toxicology
Aruna Bakhru in Nutrition and Integrative Medicine, 2018
Terms used to describe undesirable responses to drugs include: Adverse reaction. This refers to any undesirable drug effect.Side effect. This is used interchangeably with the term adverse reaction. It refers to unwanted but predictable responses to a drug.Toxic effect. This usually occurs when too much drug has accumulated in the body. It may be due to an acute high dose of a drug, chronic buildup over time or increased sensitivity to the standard dose of a drug.Drug allergy (hypersensitivity). The immune system recognizes the drug as an antigen and an immune response is mounted against the drug. This may be either an immediate or delayed response.
Antibiotic desensitization as a potential tool in antimicrobial stewardship programs: retrospective data analysis and systematic literature review
Published in Expert Review of Anti-infective Therapy, 2022
Alicia Rodríguez-Alarcón, Jaime Barceló-Vidal, Daniel Echeverría-Esnal, Luisa Sorli, Roberto Güerri-Fernández, Sofía Martina Ramis Fernández, Adela Benitez-Cano, Elena Sendra, Inmaculada López Montesinos, Estela Membrilla-Fernández, Olivia Ferrández, Ramón Adalia, Juan Pablo Horcajada, Fernando Escolano, Silvia Gómez-Zorrilla, Santiago Grau
Drug hypersensitivity is an immunologic response to medication, classified by pathogenesis and time relative to antigen exposure. Type 1 or IgE-mediated hypersensitivity reactions are of greatest clinical concern because they occur immediately and can be severe and life-threatening [15,28]. The drug antigen interacts with IgE bound to receptors on mast cells, triggering degranulation and the release of inflammatory mediators and cytokines [15,29]. Antibodies against penicillin target the beta-lactam ring, a chemical structure common in agents belonging to the penicillin drug class [30]. Although IgE-mediated hypersensitivity reactions can be life-threatening, previous literature has demonstrated that most patients labeled as allergic to penicillin are not truly allergic [1,5,6,9]. Consistent with these studies, only 25% of patients in our cohort were based on a clinical history of high-risk allergy, although none had undergone skin testing to confirm allergy. In 37% of patients, the clinical manifestations of allergy were unknown, 62% did not know when the last allergic reaction occurred and 18% of reactions had occurred more than 10 years previously. AAL is associated with receiving suboptimal treatment using drugs that are less effective and safe [3,4] and every effort should be made to de-label AAL in clinical practice.
Dapsone for the treatment of acne vulgaris: do the risks outweigh the benefits?
Published in Cutaneous and Ocular Toxicology, 2022
Selami Aykut Temiz, Munise Daye
Drug hypersensitivity syndrome is a serious idiosyncratic drug reaction determined by the clinical triad of fever, rash, and visceral involvement (most commonly the liver and the hematological system). Dapsone ranks high among drugs that reason drug hypersensitivity syndrome. Dapsone hypersensitivity syndrome (DHS) is the most serious and potentially fatal complication of dapsone. The fatal course is observed in approximately 10% of DHS cases. The severity of hepatocellular damage and previous drug sensitivity can be considered as poor prognostic signs for the outcome of the condition. For the treatment of dapsone hypersensitivity syndrome, early diagnosis, immediate discontinuation of dapsone and minimal use of other drugs should be emphasized. It usually appears on average 4 weeks (1–6 weeks) after the initiation of therapy1,42.
Data mining for detecting signals of adverse drug reaction of doxycycline using the Korea adverse event reporting system database
Published in Journal of Dermatological Treatment, 2022
Jae Young Heo, Moon Kyun Cho, Sooyoung Kim
The dermatological AEs associated with doxycycline include photosensitivity, photo-onycholysis, and various skin rashes such as erythematous, maculopapular, and pustular eruptions. The photosensitivity reactions are affected by the dose of doxycycline and the intensity of the ultraviolet (UV) A rays. Although the precise mechanisms of doxycycline phototoxicity are not fully understood, it is proposed that cell membranes, ribosomal protein, and DNA could be the chromophores in the skin and that tetracyclines induce DNA damage by photosensitizing activity (16–18). Among the signals detected in this study, AEs like blisters, erythema, mottled skin, and crusting may appear as clinical manifestations of photosensitivity reactions. In addition, signals such as skin exfoliation, angioedema, mouth edema, dry skin, mucositis, skin ulcers, and fixed eruptions are symptoms of drug hypersensitivity reactions, along with the previously mentioned dermatological symptoms (19).