McKenna's Pharmacology, 2e

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P A R T 1  Introduction to nursing pharmacology

■■ TABLE 3.1 Interventions for types of drug allergies Allergy type Assessment

Interventions

Anaphylactic reaction This allergy involves an antibody that reacts with specific sites in the body to cause the release of chemicals, including histamine, that produce immediate reactions (mucous membrane swelling and constricting bronchi) that can lead to respiratory distress and even respiratory arrest.

Administer adrenaline, 0.3 mL of a 1:1000 solution, IM for adults or 0.01 mg/kg of 1:1000 IM for children. Massage the site to speed absorption rate. Repeat the dose every 15–20 minutes, as appropriate. Notify the prescriber and/or primary caregiver and discontinue the drug. Be aware that prevention is the best treatment. Counsel the people with known allergies to wear Medic-Alert identification and, if appropriate, to carry an emergency adrenaline kit. Notify the prescriber and/or primary caregiver and discontinue the drug. Support the person to prevent infection and conserve energy until the allergic response is over. Notify the prescriber and/or primary caregiver and discontinue the drug. Provide comfort measures to help the person cope with the signs and symptoms (cool environment, skin care, positioning, ice to joints, administer antipyretics or anti- inflammatory agents, as appropriate). Notify the prescriber and/or primary caregiver and discontinue drug. Provide skin care and comfort measures that may include antihistamines or topical corticosteroids.

Hives, rash, difficulty breathing, increased BP, dilated pupils, diaphoresis, “panic” feeling, increased heart rate, respiratory arrest

Cytotoxic reaction This allergy involves antibodies that circulate in the blood and attack antigens (the drug) on cell sites, causing death of that cell.This reaction is not immediate but may be seen over a few days. Serum sickness reaction This allergy involves antibodies that circulate in the blood and cause damage to various tissues by depositing in blood vessels.This reaction may occur up to 1 week or more after exposure to the drug. Delayed allergic reaction This reaction occurs several hours after exposure and involves antibodies that are bound to specific white blood cells.

Full blood count showing damage to blood-forming cells (decreased haematocrit, white blood cell count and platelets); liver function tests show elevated liver enzymes; renal function test shows decreased renal function Itchy rash, high fever, swollen lymph nodes, swollen and painful joints, oedema of the face and limbs

Rash, hives, swollen joints

cardiac arrhythmias, caused in many people a charac­ teristic skin rash that appeared like a bright red blood vessel pattern under the skin. Although people may report that they are allergic to a drug because they develop a skin rash when taking the drug, it is important to determine whether a rash is a commonly associated adverse effect of the drug. Assessment Hives, rashes and other dermatological lesions may be seen. Severe reactions may include exfoliative derma­ titis, which is characterised by rash and scaling, fever, enlarged lymph nodes, enlarged liver and the potentially fatal erythema multiforme exudativum (Stevens–Johnson syndrome), which is characterised by dark red papules appearing on the extremities with no pain or itching, often in rings or disc-shaped patches. Interventions In mild cases, or when the benefit of the drug outweighs the discomfort of the skin lesion, provide frequent skin care; instruct the person to avoid rubbing, wearing tight

or rough clothing and using harsh soaps or perfumed lotions; and administer antihistamines, as appropriate. In severe cases, discontinue the drug and notify the prescriber and/or primary caregiver. Be aware that, in addition to these interventions, topical corticosteroids, antihistamines and emollients are frequently used. Stomatitis Stomatitis , or inflammation of the mucous membranes, can occur because of a direct toxic reaction to the drug or because the drug deposits in the end capillaries in the mucous membranes, leading to inflammation. Many drugs are known to cause stomatitis. The antineoplastic drugs commonly cause these problems because they are toxic to rapidly turning-over cells, like those found in the gastrointestinal (GI) tract. People receiving antineo­ plastic drugs are usually given instructions for proper mouth care when the drugs are started. Assessment Symptoms can include swollen gums, inflamed gums (gingivitis), and a swollen and red tongue (glossitis).