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Drug hypersensitivity reactions are a diverse group of reactions mediated by the immune system after exposure to a drug. The Gell and Coombs classification divides immunologic DHRs into 4 major pathophysiologic categories based on immunologic mechanism. Anaphylaxis is a Type I hypersensitivity reaction that requires immediate recognition and treatment. Severe cutaneous adverse reactions (SCARs) are a group of dermatologic diseases that result from a Type IV hypersensitivity process and include drug reaction with eosinophilia and systemic symptom (DRESS) syndrome, Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP). Other types of reactions are slow to develop and do not always require rapid treatment. Emergency physicians should have a good understanding of these various types of drug hypersensitivity reactions and how to approach the patient regarding evaluation and treatment., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Hypersensitivity reactions to drugs have increased in the past 25 years due to increased exposures and availability of efficient, targeted, and personalized medications. Rapid drug desensitization is a clinical procedure that allows for the safe administration of a drug in patients with a history of such hypersensitivity reactions. Desensitization allows the continued use of first-line therapies, leading to higher efficacy of treatment, fewer side effects, cost-effectiveness, and increased quality of life and life expectancy of patients when compared with the use of second-line therapy. In this review, we discuss the who, what, where, when, why, and how of drug desensitization., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Chlorhexidine-based skin preparations are frequently used in orthopaedic surgery. We report 2 recent cases of patients suffering significant allergic reactions to ChloraPrep TM complicating routine foot and ankle surgery. We advise vigilance for this possible issue and recommend thorough removal of all preparation at the end of the procedure., (Copyright © 2018. Published by Elsevier Inc.)

Hypersensitivity reactions to intravenous antibiotics are common in cystic fibrosis (CF). As well as causing immediate morbidity, the need for future avoidance of the causative antibiotic can have a long-term negative impact on CF management. This paper reviews the epidemiology and clinical presentation of hypersensitivity reactions in CF patients, and using an illustrative case describes a rare but severe form of delayed drug reaction for which a high index of suspicion is required., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: The observed associations of hyperuricaemia with hypertension, cardiovascular disease and kidney disease are receiving increasing interest. The potential role of urate-lowering therapy in the management of these "non-gout diseases" has been raised, and in some countries it is already recommended. However, there is no consistent definition of hyperuricaemia or asymptomatic hyperuricaemia, much remains unknown about the causal role of urate in these "non-gout diseases" and there is currently a lack of evidence about the effects of urate lowering on disease progression. In addition, there is potential for serious adverse effects associated with urate-lowering therapies with recent evidence suggesting that asymptomatic hyperuricaemia may be an independent risk factor for the potentially fatal allopurinol hypersensitivity syndrome., Methods: Pubmed was searched in January 2016 using the search term "asymptomatic hyperuricaemia"., Results and Conclusions: Herein, we discuss the issues related to treating asymptomatic hyperuricaemia, which at present seems premature., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Nonsteroidal antiinflammatory drugs (NSAIDs), including aspirin, are among the most commonly used drugs worldwide. They account for a large number of adverse drug reactions (ADRs). The prevalence of NSAID-induced reactions is increasing. Distinguishing between a predicted side effect of a drug and a potentially life-threatening hypersensitivity reaction is essential to manage the affected patient. However, most clinicians find it difficult to diagnose these types of reactions despite published classification schemes. In this overview, we provide an in-depth review of NSAID classification, types of NSAID reactions, diagnostic tactics, and management strategies to provide the reader with a greater understanding of NSAID-induced reactions., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The clinical efficacy of aspirin treatment after desensitization in patients with respiratory disease exacerbated by nonsteroidal anti-inflammatory drugs has been documented in observational studies and in double-blind placebo-controlled trials. There is no general agreement with regard to the optimal maintenance dose or duration of treatment with acetylsalicylic acid after desensitization, thus further studies are necessary to offer clear guidelines to clinicians. This article summarizes data from noncontrolled, active-control, and placebo-controlled trials assessing clinical effectiveness and reporting on safety of treatment with acetylsalicylic acid in desensitized patients with respiratory disease exacerbated by nonsteroidal anti-inflammatory drugs., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Drug-induced anaphylaxis is a common cause of anaphylaxis and a leading cause of fatal anaphylaxis. Antibiotics, radiocontrast, and nonsteroidal anti-inflammatory drugs are commonly implicated drugs. Vocal cord dysfunction can mimic anaphylaxis and is often overlooked. β-Lactams are a common cause of anaphylaxis; however, skin testing and drug challenge can usually determine tolerability of other classes of β-lactams. Nonionic contrast agents cause anaphylaxis less frequently than ionic contrast, and immunoglobulin E-mediated mechanisms may have a role in some of these reactions. Skin testing with radiocontrast may have a role in evaluating patients with anaphylaxis to nonionic contrast., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Several laboratories use the lymphocyte transformation test for the diagnosis of delayed-type drug hypersensitivity reactions. Recently, the availability of multiple readouts has improved our ability to diagnose reactions. It is important to note that most published studies characterizing the usefulness of diagnostic tests utilize blood samples from well-defined test and control patient groups. The purpose of this article is to briefly summarize the cellular and chemical basis of delayed-type drug hypersensitivity reactions and to review in vitro assays that are available for drug hypersensitivity diagnosis., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Use of cytotoxic agents is associated with potential hypersensitivity reactions which are common with platinum compounds, L-asparaginase, taxanes, procarbazine and epipodophyllotoxins. Mechanisms underlying the reactions may involve IgE, non-allergic or a number of pathogenetically unclear events. Targeted therapies produce less collateral damage but demonstrate their own unique reactions. Cytopenias occur less often and mucocutaneous reactions to EGFR inhibitors, including papulopustular rash, are common. Fifteen currently approved mAbs provoke all four types of hypersensitivities including immune cytopenias, vasculitis, serum sickness and pulmonary events. Some successful desensitization protocols have been developed. Prevention of hypersensitivity reactions is based on skin testing, premedication and/or desensitization., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Antiviral drugs used to treat HIV and hepatitis C are common causes of delayed drug hypersensitivities for which many of the more severe reactions have been recently shown to be immunogenetically mediated such as abacavir hypersensitivity where HLA-B(∗)57:01 is now used routinely as a screening test to exclude patients carrying this allele from abacavir prescription. Most antiviral drug allergies consist of mild to moderate delayed rash without other serious features (eg, fever, mucosal involvement, blistering rash, organ impairment. In these cases treatment can be continued with careful observation and symptomatic management and the discontinuation rate is low., (Copyright © 2014 Elsevier Inc. All rights reserved.)

In the last several years, intravenous therapy with iron products has been more widely used. Although it has been a standard procedure in dialysis-associated anemia since the early 1990s, its use is expanding to a host of conditions associated with iron deficiency, especially young women with heavy uterine bleeding and pregnancy. Free iron is associated with unacceptable high toxicity inducing severe, hemodynamically significant symptoms. Subsequently, formulations that contain the iron as an iron carbohydrate nanoparticle have been designed. With newer formulations, including low-molecular-weight iron dextran, iron sucrose, ferric gluconate, ferumoxytol, iron isomaltoside, and ferric carboxymaltose, serious adverse events are rare., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Intraoperative anaphylaxis and hypersensitivity reactions in the setting of anesthesia contribute significantly to the morbidity and mortality of surgeries and surgical procedures. Because multiple medications and products are given in a short period of time, identifying the specific cause can be difficult. Neuromuscular blocking agents, antibiotics, and latex are the most common causes of anesthesia-related reactions, though other medications or exposures could be involved. Careful review of anesthetic charts and allergy testing can help identify the underlying cause. The identification of the cause and subsequent prevention of reactions are critical to reduce overall mortality and morbidity related to anesthesia., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Poorly documented and often self-reported drug hypersensitivity (DH) is a frequent problem in daily clinical practice and has a considerable impact on prescription choices. Little is known about the natural history of true DH. The suspicion of DH starts on clinical grounds. When assessing a patient with a presumed DH reaction in the symptomatic phase, it is mandatory to look for severity signs and, after doing so, to update the risk/benefit balance of exploring the suspected drug(s) on a case-by-case basis. With the help of allergy tests and a careful approach, a firm diagnosis is often possible., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Adverse reactions to antiepileptic drugs (AEDs) may lead to treatment failure, morbidity, and mortality. Drug hypersensitivity reactions (DHRs) are potentially fatal. AED DHRs present with a variety of clinical manifestations. The pathogenesis of AED DHRs has not been fully elucidated. Bioactivation, detoxification, covalent adduct formation, presentation to the immune system, and consequent formation of antibody and T-cell immune effectors have been suggested. This article summarizes the epidemiology, pathogenic mechanisms, risk factors, clinical features, and management of allergic reactions to the aromatic AEDs carbamazepine, phenytoin, and lamotrigine., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the drugs most commonly involved in hypersensitivity drug reactions. Such reactions can be due to the release of inflammatory mediators in the absence of specific immunologic recognition, or immunoglobulin E (IgE)- or T-cell-selective responses. The former include upper and lower airway symptoms in patients with chronic underlying respiratory disease, the exacerbation of chronic spontaneous urticaria, and the induction of cutaneous symptoms. The latter include selective responses to a single NSAID with good tolerance to strong cyclooxygenase-1 inhibitors, with a putative IgE or T-cell mechanism proposed. These reactions can be acute or delayed., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Hypersensitivity reactions to excipients contained in drugs are rare but can be severe or confusing. With regard to generic versus brand drug, often the ingredients are different; for each DHR, we recommend that the physician exercises caution in considering which brand drug or generic was administered and in listing all medicine components and not only the active drug., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Although allergy to β-lactam and non-β-lactam antibiotics is commonly claimed, true allergy to these drugs is often absent. Reactions to antibiotics can be classified according to the interval between the last administration of the drug and the onset of symptoms, but except for immediate reactions occurring within an hour of exposure, which are almost always either IgE-mediated or due to direct stimulation of mast cells, reactions occurring later than 1 hour probably have multiple mechanisms, including being IgE-mediated or involving cell-mediated reactions. The latter are likely caused by drug-specific T lymphocytes. The diagnosis of antibiotic allergy can be difficult., (Copyright © 2014 Elsevier Inc. All rights reserved.)

This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Nonsteroidal anti-inflammatory drugs (NSAIDs) are cyclooxygenase inhibitors with analgesic, anti-inflammatory, antipyretic, and antithrombotic effects. NSAIDs have been implicated in a variety of drug-induced reactions that are proved as or suspected of being mediated through a host immune response. Single-drug-induced reactions are the hallmark of these types of reactions. The types of single-drug-induced reactions are the confluence of 2 variables, the structure of the drug and the specific types of immune responses. This article identifies reactions patterns and the NSAIDs most likely to elicit each immune response., (Copyright © 2013 Elsevier Inc. All rights reserved.)

It has been recognized that a high proportion of chronic urticaria patients experience symptom aggravation when exposed to aspirin and NSAIDs. This clinical picture is known as Aspirin-exacerbated cutaneous disease. The pathogenesis of these exacerbations is related to the inhibition of cyclooxygenase-1 leading to a decreased synthesis of PGE2 and an increased cysteinyl leukotriene production in the skin and subcutaneous tissues. Patient management comprises the treatment of the underlying cutaneous disease with nonsedating antihistamines and other medications, avoidance of COX-1 inhibitors, and the use of alternative NSAIDs that do not inhibit COX-1 for the relief of pain, inflammation and fever., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Dapsone is used in the treatment of autoimmune bullous diseases (AIBD), a group of disorders resulting from autoimmunity directed against basement membrane and/or intercellular adhesion molecules on cutaneous and mucosal surfaces. This review summarizes the limited published data evaluating dapsone as a therapy for AIBD., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Radiocontrast media can cause immediate (1 hour) and nonimmediate (>1 hour) hypersensitivity reactions that remain unpredictable and a cause of concern for radiologists and cardiologists. Immediate hypersensitivity reactions resemble anaphylaxis, whereas nonimmediate ones clinically are predominated by exanthemas. Increasing evidence indicates that immediate reactions and nonimmediate skin exanthemas may be allergic reactions involving either contrast media-reactive IgE or T cells, respectively. Skin testing is a useful tool for the diagnosis of contrast media allergy. It may have an important role in the selection of a safe product in previous reactors, although validation data are still lacking. In vitro tests to search for contrast media-specific cell activation are currently under investigation.

Gadodiamide is currently considered a safe alternative for use in interventional spinal procedures in persons with a documented allergic response to iodine-based contrast dyes and with adequate renal function. The most common reactions to gadodiamide are nausea, emesis, and headache. These reactions usually are self-limited and are reported to occur in less than 1% of patients. We report the cases of 4 patients who developed an allergic reaction to gadodiamide, 3 of whom presented within the same week, after minimally invasive interventional spinal procedures at an outpatient private practice facility. Furthermore, 3 of the 4 patients had previously been exposed to gadodiamide during prior interventional spinal procedures without reaction, and the fourth patient had a reaction on the first exposure. The clinical presentation was manifested as a rash in 3 of the 4 patients, whereas the fourth patient experienced fevers and rigors along with rash. Because the injections of gadodiamide were not administered in succession, different vials of gadodiamide were used in each patient, and the injections were given by different clinicians at different spinal levels, we hypothesize that these patients experienced an allergic reaction, rather than contamination of the gadodiamide solution. These cases may call into question the safety of gadodiamide as an alternative contrast agent.

We describe clinical and pathological features of kidney and skin involvement in a patient with hypersensitivity vasculitis associated with dapsone. Although visceral damage occurs rarely, similar skin and kidney histopathologic and immunohistochemical findings indicate that this organ is a target for type IV cell-mediated dapsone reaction. To our knowledge, this is the first reported case of renal hypersensitivity vasculitis associated with dapsone.

In phase II trials, the anti-epidermal growth factor receptor antibody IMC-C225 did not appear to significantly exacerbate the common toxicities associated with cytotoxic chemotherapy when combined with standard anticancer treatments in patients with colorectal cancer, squamous cell carcinoma of the head and neck, or pancreatic cancer. The most common treatment-related adverse events reported during therapy with IMC-C225 were an acne-like rash and hypersensitivity reactions. The acne-like rash appeared as a sterile, suppurative form of folliculitis, commonly starting on the face, scalp, chest, and upper back. It resolved without scarring once treatment was stopped. Notably, the appearance of acne-like rash, particularly grade 3, was associated with higher treatment responses in patients with refractory colorectal cancer. The hypersensitivity reactions occurred less often than acne-like rash. They responded to standard treatments and were less common after the first dose. In summary, IMC-C225 is generally well tolerated as a single agent and when combined with chemotherapy or radiotherapy and possesses a manageable toxicity profile., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

Sensitivity to iron dextran is a potent obstacle to maintaining optimum iron status in patients with dialysis-associated anemia. As part of the North American clinical trials for iron sucrose injection, we examined the effect of intravenous (IV) iron sucrose in 23 hemodialysis patients with documented sensitivity to iron dextran, ongoing epoetin alfa therapy, and below-target-range hemoglobin (Hgb) levels (<11.0 g/dL). We assigned patients to treatment groups according to whether reactions they had experienced to iron dextran were judged to be mild (n = 16; group A) or severe (n = 7; group B). We prospectively examined adverse events and vital signs after administering 100 mg of IV iron sucrose in each of 10 consecutive dialysis treatment sessions and compared results with those recorded in each of three consecutive dialysis sessions without iron treatment. We administered iron sucrose by IV push over 5 minutes to group A patients and by IV push over 5 minutes or IV infusion over 15 to 30 minutes to group B patients. We did not administer a test dose. Results showed no serious adverse drug reactions after a total of 223 doses of iron sucrose (184 doses by IV push, 39 doses by IV infusion). Intradialytic blood pressure changes after IV iron sucrose injection did not differ from those recorded during dialysis sessions without treatment. An increase in values for Hgb, hematocrit, transferrin saturation, and ferritin, coupled with no significant change in epoetin dose and a decrease in total iron-binding capacity, confirmed the efficacy of iron sucrose injection in managing anemia. We conclude that iron sucrose injection is safe and effective in the management of anemia in patients sensitive to iron dextran and can be administered without a test dose by IV push or infusion.

Systemic oncologic therapies can cause multiple emergency situations. There are, however, two unique emergencies directly related to chemotherapy administration: drug extravasation and hypersensitivity reactions (HSRs). Most drugs can cause varying degrees of local tissue injury when extravasated. The medical management of extravasation is based on proper maintenance of the intravenous line, application of local cooling or warming for certain extravasations, and the use of antidotes to prevent the local toxic action of the extravasated drug. Antidotes that appear useful include hyaluronidase (for vinca alkaloids, epipodophyllotoxins, and paclitaxel), sodium thiosulfate (for mechlorethamine and cisplatin), and dimethylsulfoxide (DMSO) (for anthracyclines and mitomycin C). HSRs, another potential adverse effect of chemotherapy administration, are a major concern for therapy with taxanes and with L-asparaginase, and their administration requires the use of premedication to prevent these reactions. Once a HSR has occurred, therapy may be continued by using an analog drug or by the administration of premedication as prophylaxis, in particular if the reaction was minor. On the other hand, it is also pertinent to become acquainted with the emergencies induced by biological agents, taking into consideration their increasing usages. In addition to interferons and interleukin-2 (IL-2), both of which have been in clinical use for several years, cytokine-toxin fusion proteins (DAB3891L-2) and two monoclonal antibodies (rituximab and trastuzumab) were recently approved for cancer therapy. The distinct toxicity profiles of these agents are reviewed.

Use of recombinant human erythropoietin in patients with end-stage renal disease has highlighted iron deficiency as the major cause of resistant anemia. The current mainstay of intravenous (i.v.) iron replacement therapy, iron dextran, has been shown in prior studies to have a risk of serious life-threatening anaphylaxis of just under 1 per 100 patients exposed. The current study assessed the safety profile of an alternative i.v. iron, sodium ferric gluconate complex in sucrose (Ferrlecit), as compared with iron dextrans. Sodium ferric gluconate complex in sucrose, a unique chemical preparation, has been in use since 1959, principally in Europe, at a rate of approximately 2.7 million i.v. doses per year (1992 to 1996) in Germany and Italy alone. For iron dextran, usage in the United States was comparable--principally renal hemodialysis--and estimated from market sources at 3.0 million doses per year (1995). From 1976 to 1996, there were 74 allergic adverse events reported for sodium ferric gluconate complex in sucrose to the World Health Organization (WHO), German Health Bureau, and the manufacturer (all combined). For the years 1992 to 1996, sodium ferric gluconate complex in sucrose had an allergy event reporting rate of 3.3 allergy episodes per million doses per year compared with a similar rate of 8.7 reported allergy events per million doses per year for iron dextran in the United States in 1995. Case fatalities for sodium ferric gluconate complex in sucrose and iron dextran within these reports were then compared. For sodium ferric gluconate complex in sucrose, there were no reports of deaths over the entire period (1976 to 1996). However, for iron dextrans, there were 31 fatalities among 196 allergy/anaphylaxis cases reported in the United States between 1976 and 1996, yielding a case-fatality rate of 15.8%. These data show that sodium ferric gluconate complex in sucrose, when compared with iron dextrans in comparably sized patient usage populations with similar total rates of reporting of allergic events, has a significantly lower reported mortality rate (P < 0.001). Thus, the data justify usage of sodium ferric gluconate complex in sucrose as the safer iron replacement therapeutic agent.

The animal drug approval process in the United States is based upon the premise that the presence of drug residues in meat and poultry above tolerance is a public health hazard. Tolerances represent the maximum level of concentration of antimicrobials permitted in animal tissues at the time of slaughter. The tolerances are intended to ensure that residual drugs will have no harmful effects if ingested. The purpose of this article is to present existing evidence of the acute and chronic health consequences that may occur because of food of animal origin contaminated with illegal residues above the tolerance. The impact of food-borne drug residues on the gut microflora, residue detection limitations, and the responsibility of the veterinary practitioner in ensuring food safety is discussed.

WinRho anti-D is manufactured with multiple processes to minimize the risk of transmitting blood-borne diseases such as viruses. These safety features include donor selection, plasma testing, solvent-detergent viral inactivation, and nanofiltration. To date, there has not been any case of viral transmission in association with use of WinRho anti-D. Adverse drug reactions are infrequent and generally mild; the most common are headache, fever, and chills. Some degree of hemolysis is inevitable due to the mechanism of action of WinRho anti-D, but this is predictable and transient. A few cases of intravascular hemolysis have been reported; hypersensitivity reactions are very rare. WinRho anti-D has been shown in both clinical trials and postmarketing surveillance to be safe and effective in the treatment of idiopathic thrombocytopenic purpura (ITP) and in the prevention of Rh isoimmunization.

To examine the toxicity profile and antineoplastic activity of carboplatin (area under the concentration-time curve of 4 to 7.5) plus 3-hour infusional paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) (135 or 175 mg/m2) in women with advanced gynecologic malignancies, we retrospectively reviewed the experience of the Gynecologic Cancer Program at The Cleveland Clinic with this combination chemotherapy regimen. To date, 92 patients (median age, 67 years) have received a total of 460 courses (median number per patient, six) of this two-drug combination. The initial paclitaxel dose was 175 mg/m2 and the carboplatin area under the concentration-time curve was > or = 5 in 72% and 73% of patients, respectively. The major toxicity was neutropenia (grade 4 in 9% of patients), resulting in two febrile episodes and a single septic death. Grade 4 thrombocytopenia and grade 3 peripheral neuropathy were noted in one and two patients, respectively. Twelve patients (13%) experienced at least one episode of paclitaxel-associated hypersensitivity, but all were able to continue with the treatment program. Of the 62 patients with ovarian cancer or primary peritoneal carcinoma with carbohydrate antigen-125 levels > or = 60 U/mL before the initiation of chemotherapy, 74% exhibited a > or = 90% decline in the tumor marker following treatment. We conclude that the combination of carboplatin and 3-hour infusional paclitaxel can be administered in the outpatient setting with a highly acceptable toxicity profile and with major activity in patients with ovarian cancer and primary carcinoma of the peritoneum.

A case of opioid withdrawal precipitated in an opioid-dependent person by low plasma levels of naloxone is presented. In this patient, changes were observed in the hypothalamic-pituitary-adrenal (HPA) axis that preceded the clinical symptoms and adrenergic signs of withdrawal. Plasma naloxone levels were strongly correlated with plasma cortisol levels (P < .0001, R2 = .73, r = .85). In addition, these neuroendocrine changes persisted after adrenergic changes and clinical symptoms had been ameliorated by administration of a short-acting opioid agonist. It is suggested that the HPA axis is a more sensitive indicator of opioid withdrawal than the adrenergic system.

The increased number of drugs used in anesthetic practice today as well as cross-sensitivity between drugs, have lead to a higher risk of allergic responses. This article describes the evolution and treatment of an allergic reaction, discusses the classification of allergic responses, and details the treatment of anaphylactic/anaphylactoid reactions. The allergic potential of drugs commonly used in the administration of anesthesia is highlighted.

The neutralization of heparin anticoagulation is accomplished by the administration of protamine. While the administration of protamine is generally uneventful, allergic reactions can occur. This article describes such a reaction in a patient having cardiac surgery. Classification of protamine reactions and signs and symptoms are discussed. Treatment and management of high risk patients is highlighted.