Chapter 4 Immunologic Drugs and Vaccines © Paradigm Publishing, Inc. 2 Chapter 4 Topics • • • • • • Physiology of Acquired Immunity Immunization Interferon Therapy Immunosuppression Immunoglobulins, Antitoxins, and Antivenoms Herbal and Alternative Therapies © Paradigm Publishing, Inc. 3 Physiology of Acquired Immunity Acquired Immune Response • Body’s built-in defense mechanism against pathogens • Systemic response Pathogens are carried to the lymph nodes Lymphocytes then detect and destroy pathogens © Paradigm Publishing, Inc. 4 Physiology of Acquired Immunity Acquired Immunity • Helper T cells Detect specific antigens (molecules on foreign pathogens) Stimulate killer T cells and B cells to become active • Killer T cells attack cells infected with foreign antigens • B cells make antibodies or immunoglobulins (Ig) • Immunoglobulins fight infection by binding viruses and preventing them from infecting healthy cells © Paradigm Publishing, Inc. 5 Physiology of Acquired Immunity Immunoglobulins (Ig) IgA In mucous membranes of digestive system and respiratory tract, tears, sweat, and saliva IgD In plasma and on surface of lymphocytes; possibly involved in B cell maturation IgG Most common antibody; small amounts produced after first exposure to pathogen, large amounts produced subsequently IgE In basophils and mast cells; mounts allergic response; fights parasites IgM First antibody produced after exposure to pathogen; activates complement system; on surface of red blood cells; responsible for A, B, and O blood typing © Paradigm Publishing, Inc. 6 Physiology of Acquired Immunity Autoimmune Disorders • The immune system can malfunction and begin producing antibodies against normal, healthy cells • Examples: SLE, myasthenia gravis, rheumatoid arthritis, MS, and type 1 diabetes Each disorder affects specific tissues, depending on the type of antibodies produced and the cells they attack Type 1 diabetes is caused by an autoimmune process that destroys beta cells that produce insulin in the pancreas © Paradigm Publishing, Inc. 7 Physiology of Acquired Immunity Allergic Reactions • Immune system mediates allergic reactions; also called hypersensitivity reactions • Four types of hypersensitivity reactions (Type I, II, III, IV) • Type I reactions cause anaphylaxis; can be life threatening if not treated immediately Anaphylaxis: process mediated by antibodies, basophils, and mast cells Causes swelling of airways, blood vessel dilation, shock • Type II reactions stimulate the complement system; occur when the wrong type of blood is given to a patient © Paradigm Publishing, Inc. 8 Physiology of Acquired Immunity Allergic Reactions (continued) • Type III reactions involve toxins and antibodies • Type IV reactions involve killer T cells Also called delayed responses; take 12–72 hours to occur Example: tuberculin skin test for tuberculosis When drugs cause Type IV reactions, hives or itchy rash occur Not harmful if drug is stopped Can progress to anaphylaxis if drug is continued © Paradigm Publishing, Inc. 9 Immunization Immunization • Uses acquired immunity to fight specific diseases • Natural immunization occurs when the body is exposed to foreign antigens in daily life Produces antibodies against foreign antigens Can quickly defend and protect from getting sick again • Artificial immunization occurs when an antigen is intentionally introduced to the body via vaccination Builds a defense in advance of disease exposure Can be accomplished through active or passive means © Paradigm Publishing, Inc. 10 Immunization Two Types of Artificial Immunization • Active immunity The body is exposed to an antigen or part of an antigen; natural immune response makes antibodies Vaccines use active immunity to prevent disease; body introduced to killed, weakened, or partial antigens Some vaccines (called live attenuated vaccines) use live, weakened pathogens to produce an immune response • Passive immunity Antibodies introduced into bloodstream naturally (pregnancy) or artificially (injecting immunoglobulins) © Paradigm Publishing, Inc. 11 Immunization Vaccination • Used to reduce and prevent life-threatening diseases Polio, smallpox, measles, and influenza • Several vaccines require multiple doses • CDC publishes an Immunization Schedule for Adults (see Figure 4.2) • Healthcare professionals should be informed of immunization schedules and stay current Recommended: hepatitis B and annual influenza shot BCG vaccine for tuberculosis may be required © Paradigm Publishing, Inc. 12 Immunization Common Vaccines • Most administered in physician’s office and inpatient settings Vaccines Commonly Handled by Pharmacy Technicians (see Table 4.2) • More now administered in pharmacies: flu shots, travel vaccines, pneumonia, and shingles • Many pharmacies operate travel immunization clinics Common travel vaccines: hepatitis A, cholera, malaria • Vaccines are fragile proteins Routes: usually injection; few in oral form • Pharmacy technicians order, store, and prepare vaccines © Paradigm Publishing, Inc. 13 Immunization Common Vaccines (continued) • Many patients now get their annual flu shots at their local pharmacies © Paradigm Publishing, Inc. 14 Immunization Common Vaccines (continued) • Side Effects: fever, headache, stomach upset, local injection site irritation, mild rash, and irritability Take acetaminophen 24–48 hours after immunization to reduce symptoms • No link between autism and preservatives in vaccines • Cautions (prior to administration of vaccines): Patients receive written risk information; see VIS Patients sign consent form No vaccine for patients with egg allergy © Paradigm Publishing, Inc. 15 Immunization Common Vaccines (continued) • Cautions: storage and preparation unique for each vaccine Refrigerate or freeze most Check for required temperature range Warm frozen vaccines to room temperature; then use right away Take daily temperatures of refrigerators and freezers Use prepared vaccines within minutes to hours Do not prepare multiple doses © Paradigm Publishing, Inc. 16 Your Turn Question 1: Many employers require pharmacy technicians to get the BCG vaccine. What is the purpose of this vaccine? Answer: The BCG vaccine immunizes healthcare workers who have high risk of exposure to active tuberculosis. Question 2: A traveler received a vaccine for cholera. During his trip, the patient became ill with cholera. What may have caused this to happen? Answer: The patient may not have waited long enough to allow the immune system to provide full immunity. © Paradigm Publishing, Inc. 17 Interferon Therapy Interferons • • • • • Used for variety of conditions, including MS and hepatitis Costly; usually dispensed in specialty pharmacies Protein products that degrade easily Store in the refrigerator Administration: inject when at room temperature Slowly roll the product between palms of hands to warm it © Paradigm Publishing, Inc. 18 Interferon Therapy Multiple Sclerosis (MS) • Autoimmune disorder; antibodies destroy myelin sheath surrounding nerve cells Scars form, interfering with signal conduction of nerves Numbness in limbs, loss of nerve axons and white matter in the brain, vision loss, and paralysis Relapsing-remitting MS is the most common type Drugs for MS • Interferons prevent progression and relapse • No flu shot with interferon therapy © Paradigm Publishing, Inc. 19 Interferon Therapy Hepatitis • Inflammation of the liver caused by viral disease, alcohol use, medications, poisons, or autoimmune diseases • Hepatitis A transmitted by consuming contaminated food or liquids; short-term, acute infection only • Hepatitis B transmitted by sexual activity, contaminated needles, infected blood products, or mother to infant Begins as acute infection that mimics flu-like symptoms or is asymptomatic Can lead to chronic liver infection such as cirrhosis, liver cancer, and liver failure © Paradigm Publishing, Inc. 20 Interferon Therapy Hepatitis (continued) • Hepatitis C transmitted by blood-to-blood contact High-risk populations include injection drug users, homeless, and prison inmates Most patients develop chronic liver infection Drugs for Hepatitis • No treatment required for hepatitis A • Vaccines prevent hepatitis A and B; healthcare workers receive three-injection series for hepatitis B • Interferons used for chronic infection in hepatitis B and C © Paradigm Publishing, Inc. 21 Immunosuppression Organ Transplant • When someone receives an organ transplant T cells detect and attack the foreign tissue B cells make antibodies against it The body will reject the implanted organ unless immunosuppression starts right away • Tissue typing is performed to match organ donation Reduces chance of organ rejection, but risk remains • Graft versus host disease is when T cells in transplanted organ attack the recipient’s body after transplant © Paradigm Publishing, Inc. 22 Immunosuppression Immunosuppressants • Medications that suppress immune system activity to prevent rejection of a transplanted organ • Indications: taken for life after receiving a transplant Also suppress autoimmune disorders such as rheumatoid arthritis, SLE, and psoriasis • Mechanism of Action: inhibit T cell and B cell activity • Side Effects: sore throat, cough, dizziness, nausea, muscle aches, fever, chills, itching, and headache © Paradigm Publishing, Inc. 23 Immunosuppression Immunosuppressants (continued) • Serious Side Effects (rare): heart rhythm or blood pressure changes, chest pain, unusual bleeding, bruising, anemia, and hyperlipidemia Muromonab can cause severe pulmonary edema (fluid accumulation in the lungs) on first dose • Cautions: patients must minimize exposure to infection due to higher risk • Routes: IV; also oral, IM injections, and SC injections IV dosage forms require special handling and mixing © Paradigm Publishing, Inc. 24 Immunosuppression Immunosuppressants (continued) • Some IVs refrigerated; some protected from light • Do not shake IVs; use within limited time from mixing Cyclosporine should be prepared in glass containers • Special administration instructions Oral tacrolimus should not be taken with antacids Sirolimus can be taken with or without food consistently Some agents given as IV infusions; some given as IV bolus injections • Some agents have serious drug interactions © Paradigm Publishing, Inc. 25 Immunosuppression Oral Corticosteroids • Systemic oral agents with anti-inflammatory and immunosuppressant properties; decrease fever, redness, and swelling • Modify immune response by slowing leukocyte function • Indications (short term, high doses): hypersensitivity, allergic reaction, and asthma exacerbations • Indications (long term): protection from organ transplant rejection and used for treatment of rheumatic and some autoimmune disorders • Side Effects: headache, dizziness, insomnia, and hunger © Paradigm Publishing, Inc. 26 Immunosuppression Oral Corticosteroids (continued) • Side Effects (long-term): change in normal metabolism, facial swelling (moon face), major weight gain, fluid retention, and fat redistribution to back and shoulders (buffalo hump) • Severe Side Effects: high blood pressure, loss of bone mass (osteoporosis), electrolyte imbalance, cataracts, glaucoma, insulin resistance (diabetes), and steroid-induced psychosis • Routes: all oral; some IM and IV • Cautions: do not stop using abruptly; causes increased risk of infection Can stunt growth in children if used long term © Paradigm Publishing, Inc. 27 Immunoglobulins, Antitoxins, and Antivenoms Immunoglobulins • Provide artificial passive immunity quickly through injected exogenous antibodies Immunity only lasts a few months; no boosters required • Indications: rabies, tetanus, chickenpox, shingles, and RSV Antitoxins and Antivenoms • Antibodies in agents combine with the toxin or venom to neutralize it Example: Rh factor immune globulin used for negativeblood-type woman carrying a positive-blood-type child © Paradigm Publishing, Inc. 28 Immunoglobulins, Antitoxins, and Antivenoms Antivenoms (continued) • Also called antivenins • Indications: spider bites (black widow spiders); snakebites (rattlesnakes, copperheads, and North American coral snakes) • Route: most by IV within 4 hours of the bite • Prepare orders immediately and rush to ER for administration Warm refrigerated agents by gently rolling vials between the palms of the hands © Paradigm Publishing, Inc. 29 Your Turn Question 1: What is the purpose for storing interferons in the refrigerator? Answer: Interferons are fragile proteins that easily degrade. Refrigerating these agents helps keep the proteins from breaking down. Question 2: A patient is at a county fair. She is wearing a face mask and often uses a hand sanitizer. What is the likely reason for her precautions? Answer: The patient is likely being treated with immunosuppressants and is at increased risk of infection. © Paradigm Publishing, Inc. 30 Herbal and Alternative Therapies • Limited herbal and alternative therapies available for autoimmune disorders, hepatitis, or immunosuppression • Vitamin D supplementation may help decrease risk of MS in women; no recommended dose © Paradigm Publishing, Inc. 31 Summary • Immunization uses acquired immunity to protect against specific diseases • Vaccinations trigger production of antibodies to protect against specific diseases • Interferon therapy is used to treat autoimmune disorders • Immunosuppressants inhibit the immune system from attacking transplanted tissue after organ transplant • Immunoglobulins in antitoxins and antivenoms provide rapid immunity for specific diseases © Paradigm Publishing, Inc. 32