McKenna's Pharmacology for Nursing, 2e

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C H A P T E R 1 8  Vaccines and sera

TABLE 18.2

DRUGS IN FOCUS Immune sera (continued)

Drug name

Dosage/route

Usual indications

Antitoxins and antivenins (continued) stonefish antivenom (generic)

2000–6000 U IM or IV depending on number of punctures

Systemic envenoming following bite from stonefish, with severe oedema and pain not responsive to first aid Systemic envenoming following bite from taipan Systemic envenoming following bite from tiger, copper head or black snake

taipan antivenom (generic)

12,000 U by slow IV diluted in Hartmann’s solution 3000 U by slow IV diluted in Hartmann’s solution

tiger snake antivenom (generic)

Contraindications and cautions Immune sera are contraindicated in individuals with a history of severe reaction to any immune sera or to products similar to the components of the sera to prevent potential serious hypersensitivity reactions. They should be used with caution during pregnancy because of potential risk to the fetus ; with coagulation defects or thrombocytopenia; or in individuals with a known history of previous exposure to the immune sera because increased risk of hypersensitivity reaction occurs with each use. Adverse effects Adverse effects can be attributed either to the effect of immune sera on the immune system (rash, nausea, vomiting, chills, fever) or to allergic reactions (chest tightness, falling blood pressure, difficulty breathing). Local reactions, such as swelling, tenderness, pain or muscle stiffness at the injection site, are very common. Prototype summary: Immunoglobulin, normal (human) Indications: Prophylaxis against hepatitis A, measles, varicella, rubella; prophylaxis for people with immunoglobulin deficiency. Actions: Provides preformed antibodies to hepatitis A, measles, varicella, rubella and perhaps other antigens, providing a passive, short-term immunity. Pharmacokinetics: Route Onset Peak IM Slow 2–5 days T 1/2 : Unknown; metabolised in the tissues, excretion is unknown. Adverse effects: Tenderness, muscle stiffness at site of the injection; urticaria, angio-oedema, nausea, vomiting, chills, fever, chest tightness.

Clinically important drug–drug interactions Caution should be used if these drugs are combined with any immune suppressant drugs, including cortico­ steroids. These can alter the body’s response to the biologicals.

Care considerations for people receiving immune sera

Assessment: History and examination

■ ■ Assess for contraindications or cautions: any known allergies to any of these drugs or their components to prevent hypersensitivity reactions ; current status related to pregnancy, which would be a contraindication for immune sera ; previous exposure to the serum being used because hypersensitivity reactions become worse with repeated exposure ; evidence of thrombocytopenia or coagulation disorders, which could be exacerbated by the effects of immune sera ; and immunisation history to determine the potential for hypersensitivity reactions . ■ ■ Perform a physical assessment to determine baseline status before beginning therapy and for any potential adverse effects : Inspect for the presence of any skin lesions to monitor for hypersensitivity reactions ; check temperature to monitor for possible infection ; monitor pulse, respirations and blood pressure; auscultate lungs for adventitious sounds; and assess level of orientation and affect to monitor for hypersensitivity reactions to the vaccine . Implementation with rationale ■ ■ Do not administer to any individual with a history of severe reaction to immune globulins or to the components of the drug being used because severe immune reactions can occur . ■ ■ Administer the drug as indicated. Preparation varies with each product; always check the manufacturer’s guidelines .