NUR 239 MEDICATIONS (ANTBIOTICS) STUDY GUIDE- Molloy College

Medications (antibiotics) Mosby- Pharmacology drug guide Antimicrobials: Antibiotics - Penicillins & Cephalosporins - Macrolide and Lincosamides - Tetracyclines and Glycylcyclines - Aminoglycosi des - Fluoroquinolones and Lipopeptides - Sulfonamides Selection of Antibiotics - Usually based on signs and symptoms, host cell specificity and HCP experience - Most are broad spectrum or gram positive or gram negative. Some very specific to one organism (ex vancomycin is only met that will kill Legionnaires bacteria) - Bacteriostatic vs Bacteriocidal issues Selection of Antibiotics - Pts should feel better in 2-3 days. If not: • Is it wrong drug for this organism? • Is it resistant strain of the organism? • Is it really bacterial? Could it be viral? • Need gram stain, culture and sensitivity? • It is Nurses’ job to evaluate effectiveness of tx, notify HCP, check labs for sensitivity Antibiotic Resistance - Resistance: organism has mutated and med no longer works. Very serious issue today - Causes: • Pt take until they feel better and save rest. Weak bacterial killed and strong survive • HCP prescribe antibiotics for viruses to keep its happy. Exposed bacteria stronger • Chronic low level exposure in food and water • Bacteria share gene snippets for resistance - Common side effects • Allergies: most likely meds to cause them - Always check allergy hx - New allergies may start right away, near end of Rx or 2nd or at any time - Usually generalized rash, hives, itch, swelling- may be immediate or later - Stomach or nerve pain not true allergy; be sure to distinguish from side/ adverse effects • GI upset: stomach pain, nausea, diarrhea - Milk and milk products will not let the meds absorb in the stomach- separate them from antibiotic by about 2 hours • Superior- infection: another infection with a different organism, such as yeast or C. Diff - More than one infection- is a hard to kill bacteria- stays on hard surfaces for a long time, easy to contaminate • Photosensitivity- rash or severe sunburn • Nephrotoxicity: injury to the kidneys - Drink fluids to flush the medication out of the body - BUN and Creatinine- make sure levels are not elevated, need extra fluid before giving antibiotics • Neurotoxicity: injury to nervous system - Ototoxicity- loss of hearing from some meds, nerve damage in the ear • Med interactions: may increase or decrease - Some antibiotics have a longer half life and stay in the system longer Treatment for drug allergies - Stop the drug. Avoid drugs in the same class for life - Mild: antihistamines like Benadryl - moderate: add topical or oral steroids - Severe: IV steroids, antihistamines, titrate to orals - Life threatening: epinephrine, IV steroids, antihistamines, supportive respiratory care GI Effects: Understand and Treat - Upper GI: Pain, Nausea, Vomiting • antibiotics irritate stomach lining. Check info to see if able to take with food. Do to recommend milk or antacids. May bind and prevent absorption - Lower GI: diarrhea • Usually due to killing normal flora; starts day 7-10. Recommend probiotics or eating yogurt; separate from meds by 2 hours or more • Distinguish from Clostridium difficile, a super- infection. Incontrollable orange diarrhea, sour odor, dehydration. Tx with vancomycin Other Super Infections - Common super infections from antibiotics • Thrush: candida albicans (yeast) in mouth • Vaginal/ Genital: yeast- males and females • Skin: frequently in moist areas, ie skin folds, yeah infection, severe diaper rash • Eye: other bacteria, viruses, or fungi/yeast • GI: Photosensitivity - Instruct pt to avoid sun - Wear long sleeves and hat - Use sunscreen liberally - Do not put butter or cold cream on sunburn. Cool baths or compress, anti- inflammatory med, pain med as per HCP, do not pop blisters - Aloe after healing starts Nephrotoxicity: Understand and Tx - Antibiotics concentrate in kidneys and burn lining of nephrons, which sough off and clog tubules. Key is to dilute urine - Check hydration status of pt first. If dehydrated, correct before starting and during antibiotic tx. - Encourage PO fluids, keep urine light yellow - Check for hx of renal disease and/ or BUN and creatinine levels. HCP may reduce dose - Beware of gentamicin and vancomycin. May cause acute renal damage and anuria on the first dose. • Peak and trough levels - Elderly and diabetics more likely to have problems Neurotoxicity: Understand - Nerve damage can include: • Cochlear dysfunction: dizziness, poor balance, incoordination, nausea, vomiting • 8th cranial nerve: tinnitus, ototoxicity, deafness • Neuropathies or parathesias: numbness, tingling, burning, shooting, electric shock type pains, usually hands and feet • Elderly, alcoholics, and diabetics most prone to it • Most common with gentamicin and vancomycin- monitor peak and trough levels • Draw peak level- half hour after infusion has finished - coordinated with the time the medication is given Antibiotics Interactions - Medications • May reduce effectiveness of hormonal BC • May alter levels of protein- bound drugs, including Coumadin and Sulfonylureas - Foods • Milk, milk products, and antacids bind with antibiotics and prevent absorption • Cephalosporins cause and antabuse-like reaction with alcohol. Flushing, chest pain, shortness of breath. Tx symptomatic in ER Patient Teaching for all antibiotics - Contact HCP if not feeling better in 3 days - Finish Rx even if feeling better. Do not save - Drink extra fluids - Use sunscreen, wear long sleeves and hat - If stomach upset occurs take with food if OK - If diarrhea occurs, eat probiotics or yogurt - If diarrhea worsens, contact HCP - If allergy occurs, stop med and contact HCP - If using HBP be sure to use backup method Classes of Antibiotics - Penicillins - Cephalosporins - Fluoroquinolones - Macrolides - Lincosamides - Aminoglycosides - Urinary tract specific drugs - Tuberculosis specific drugs Penicillins- Penicillin G - Amoxicillin, Pen VK - Uses: inhibits bacterial cell wall synthesis - For treating strep, staph, pneumococcal, fusospirochetal infections, syphilus, gonorrhea, meningococci infections. Does not cross the blood brain barrier well - Routes: PO, IM, IV (PB) • IV- penicillin V is more stable. Iv solutions usually kept refrigerated • PO- taken on empty stomach • Adverse effects: allergies***- mold • GI upset • diarrhea- disruption of the normal flora- assess symptoms of adverse effects-probiotics or yogurt, • superinfection-another infection on top of what you already have (usually yeast) • Thrombocytopenia- loss of/not enough platelets- excessive bruising • nephritis- kidney inflammation- check BUN and creatinine, urine output. Hydrate patient before med administration - Contraindications: allergies, renal disease, pregnancy lactation - Interactions: • May inactivate parenteral aminoglycosides • Oral probenecid slows excretion of the drug and increases penicillin levels for greater effect • May inactivate oral contraceptives. Women should use a backup therapy during therapy Cephalosporins (Cefazolin, Ancef, Keflin, Kefzol) - Uses: Bactericidal and bacteriostatic. Interferes with the ability of the bacteria to build cell walls when they are dividing. Treats resp infections, infections, sinus, ear, GI, skin, bone, heart, and blood infections- cousins of penicillins - Nephrotoxic and neurotoxic - Adverse effects: allergies • Serum sickness • GI- nausea, vomiting, diarrhea • headache, dizziness, lethargy • paresthesias • phlebitis (IV) - Contraindications: 5% risk of all cross- sensitivity with penicillins. Lactating women, pregnant women, renal failure its - Interactions: avoid alcohol for 72 hours after finishing the drug (may cause flushing, SOB, chest pains, palpitations) may increase the risk of nephrotoxicity when given with aminoglycosides. May increase bleeding in patients taking Coumadin. May cause false + in urine sugar tests Fluoroquinolones (Ciprofloxin, Cipro, Ciloxin) - Uses: Bactericidal; inhibits DNA replication. • Selective toxicity: does not affect human cells • Does not cross the blood brain barrier. Most active against aerobic gram negative bacteria such as e coli. Also active against aerobic gram + organisms and sexually transmitted diseases - Routes: Oral and IV - Adverse effects: tendon rupture- especially achilles tendon, shoulder, hands • Photosensitivity- light sensitivity, sun, rashes from sun - Photophobia- different than photophobia • Nephritis • Rash • Fever • Eosinophilia- WBC, levels high in allergies and asthma • Occasionally palpitations and arrhythmias • GI upset • HA- headache • Restlessness - Contraindications: colitis, renal or hepatic disease, dehydration, pregnant. Lactating or allergies - Interactions • Salts will bind with Cipro. Avoid foods and meds containing aluminum, calcium, iron, magnesium, zinc • May cause theophylline toxicity • Caffeine may interrupt action of Cipro • Decreases vitamin absorption Amnoclycocides- Gentamycin- only IVPB - Uses: bacteriostatic and bactericidal. Enters cells wall and binds to ribosomes, prevents bacterial reproduction and weakens cells wall. Often given with synergistic antibiotics to increase effectiveness or alter cell wall so aminoglycoside can enter - Infection include UTI. peritonitis, endocarditis, PNA, sepsis, resp infections with CF, osteomyelitis, diabetic foot infections - Routes: IV, maybe IM- no PO - Adverse effects: • Nephrotoxicity- kidney • Ototoxicity- ear infection/loss of hearing - Assess hearing before starting the medication • Neuromuscular blockade - Toxicity occurs frequently. Important to maintain therapeutic levels. Peak and trough levels should be done frequently (q3 days) - May induce confusion, depression, disorientation, numbness, tingling, weakness • Fall risk - Leukemoid reactions and depressed bone marrow may occur • Leukemia- immature WBC - May induce palpitations, hypo or hypertension - GI symptoms: hepatotoxicity, nausea, diarrhea - Patient is toxic- does not stop medication completely- hold medication temporarily and resume shortly after- benefit outweighs the risk - Contraindications: allergy, pregnancy, lactation. Cautious use in renal or hepatic disease, dehydration, pre-existing hearing loss, myasthenia gravis (reduces acetylcholine- muscle weakness, nerve disorder), Parkinsonism, infant botulism • Do not mix with other ototoxic drugs (acyclovir, amphotericin B, cisplatin, vancomycin, lasix, aspirin) May also interact with anesthetics • Administer gent and extended penicillin such as carbenicillin or ticarcillin at least 2 hours apart - Similar drugs: amikacin, kanamycin, tobramycin, streptomycin - MYCIN= TOXIC - Neomycin: used topically and as GI disinfectant - Streptomycin: treat TB - Paromomycin: used orally to decrease ammonia- forming bacteria in hepatic coma Macrolydes- Erythromycin - Uses: Bactericidal and bacteriostatic. Specific for Legionnaires Disease- also good alternative to penicillins. Gram + organisms, pneumonias, chlamydia, Lyme disease, and some parasites - Routes: PO or IV, ocular - Adverse Effects: allergies, pseudomembranous colitis (, inflammation of the colon), prolonged QT interval and ventricular tachycardia, *tinnitus and reversible hearing loss - Contraindications: allergies, pregnancy and lactation, impaired hearing, impaired hearing, impaired hepatic or biliary function, GI diseases cardiac arrhythmias. Nor for use on viral, fungal, or mycobacterial infections of the eye Lincosamides- Clindamycin, Lincomycin - Uses: Bactericidal- suppress protein synthesis. Useful against a wide range or aerobic gram + cocci, strep, staph, pneumococci. Also used topically to treat acne. Crosses blood brain barrier - Adverse Effects: GI, nausea, vomiting, diarrhea, colitis, pseudomembranous colitis,. Thrombocytopenia, neutropenia, eosinophilia. Allergies - Contraindications: allergies, pregnancy, lactation - Interactions neuromuscular blockers. Topical applications may have cumulative effects with other topicals, leading to peeling and drying of skin Tetracyclines - Uses: crosses the blood brain barrier. Semi-synthetic, effective for mycoplasma pneumonia, flu, e. coli, klebsiella, staph aureus, acne, chlamydia, and as an ophthalmic drug - Routes: No longer available IM or IV. PO or ophthalmic - Adverse effects: GI upset, photosensitivity, allergies, hepatic toxicity and fatty liver, high potential for superinfection, hemolytic anemia, and bone marrow depression - Contraindications: allergies, pregnancy, lactation, children under 8 (stains their teeth), hepatic and renal dysfunction - Interactions: decreased effectiveness of penicillin G and oral contraceptives. Not absorbed with dairy foods, antacids Vancomycin - Uses: Bactericidal. Inhibits cell wall synthesis. Severe infections such as bacterial septicemia, endocarditis, bone and joint infections, pseudomembranous colitis, staph, strep, clostridium gram + infections in penicillin allergic patients. Works on methicillin resistant organisms - Routes: IV, poorly absorbed PO - Adverse effects: ***ototoxicity and nephrotoxicity. Can cause anaphylactoid reactions, “Red man syndrome” or “red neck syndrome”. Causes facial flushing, paresthesias, redness of face, neck, and upper body, arms, and back. Sometimes hypotension due to histamine release. Fever, chills, sinus tachycardia, pruritus. Can also cause leukopenia and thrombocytopenia - Contraindications: allergies, pregnancy. Use with caution with aminoglycosides due to ototoxic effects - Special Considerations: always administer slowly (60 min or more) to reduce the risk of Red man syndrome. Monitor serum concentrations to reduce toxicity. Avoid extravasations- very irritating to tissues • Use central line or check the IV ahead of time to make sure that it is safe- treat differently if there is extravasations- treat it like a burn Chloramphenicol - Uses: Very toxic, only drug in its class - Routes: IV, otic, ophthalmic, topical - Adverse effects: Gray Baby Syndrome can cause vasomotor collapse and bluish-gray skin color in newborn and premature babies • Blood dyscrasias, Aplastic anemia, thrombocytopenia, pancytopenia, granulocytopenia, bone marrow depression which may be irreversible. May occur months after treatment or after a single dose. May be fatal • Optic neuritis- may cause blindness (inflammation of the optic nerve) • Peripheral neuritis, CNS symptoms, confusion • GI effects, rash - Interactions: oral hypoglycemic, oral anticoagulants, iron salts, B12, other antibiotics Antitubercular Drugs - Isoniazid • Antibacterial effect against mycobacterium. Can cross the blood-brain barrier. Inactivated in the liver, excreted In urine, feces, saliva, sputum • Routes: Oral, triple antibiotic therapy - Liver toxic- check for hepatitis and alcohol abuse - Isoniazid, rifampin, ethambutol • Adverse reactions: hepatitis, peripheral neuropathy, endocrine changes, GI reactions, reactions, rash, hematologic alterations • Contraindications: hepatic disease, alcoholism, severe renal impairments, DM, malnutrition, seizure disorders • Interactions: antiseizure medications, aluminum antacids, benzodiazepines, meperidine, oral anticoagulants, rifampin/ Has some MAO inhibitor activity. Avoid tyramine-containing foods and foods with histamine - Rifampin: can accelerate the metabolism of multiple drugs, decreasing their efficiency, especially anti fungal and antiretroviral drugs. Should try to avoid use with protease inhibitors. May discolor saliva, tears, sputum (Red) - Ethambutol: effective only against rapidly dividing bacteria. Metabolized in the liver, excreted in urine and 25% unchanged in feces. Able to cross inflamed CSF. No adverse to fetus or nursing infant • Adverse effects: optic neuritis** should have eye exam first. Do not use on children who can't be tested. May also cause hyperuricemia, so use carefully with gout - PZA, streptomycin- also can be used for TB, mostly used for children with TB Urinary Tract Drugs - Sulfonamides: • Prototype Sulfamethoxazole/ Trimethoprim, Brand names: SMZ-TMO and Bactrim • Uses: Crosses blood-brain barrier. Inhibits synthesis of folic acid. UTI, URI, HIV, Pneumocystis carinii pneumonia, salmonella, shigella, gonorrhea • Routes: Oral, IV • Adverse effects: allergies, crystalluria, anemia in pts with folate deficiency. Photosensitivity may continue for months after use. May displace other protein- bound drugs such as oral hypoglycemics, oral anticoagulants, dilantin (anti-seizure) and methotrexate • Contraindications: allergy to sulfa, G6PD deficiency, pregnancy, lactation and infants - Phenazopyridine (Pyridium): is a dye that has an analgesic effect on the urinary tract. Pt teaching should include the fact that it will turn the urine a bright orange color Antifungal Drugs - Nystatin (Mycostatin) topical, vaginal, oral. Used against candida. Oral forms contain sucrose, which mat add to hyperglycemia. May cause vomiting, diarrhea, abdominal pain, skin irritation, rash, urticaria (yeast infection) - Griseofulvin (Fulvicin U/F) used to treat ringworm and tine. May be needed for 6-12 months until infected skin completely grown out. PO may cause GI upset. Decreased effectiveness of birth control pills and Coumadin. Increases effects of alcohol - Fluconazole: usually used for candida of the mouth or vagina. May be given orally or IV. No contraindications. May cause GI upset, rarely Stevens-Johnson syndrome in HIV patients - Amphotericin B “amphoterrible” • Actions: IV fungal. Used for systemic potentially fatal fungal infections and some protozoan. Also available in topical creams, lotion, or ointments. Very long half life: 4 weeks in blood and 4-8 weeks In urine • Adverse reactions: sometimes called “shake and bake” HA, chills, fever, rigors, hypotension, bronchospasm, nausea, vomiting, severity decreases with subsequent doses - Electrolyte imbalances: drop in K, Ca, Mg,Cl- May exacerbate preexisting cardiac disorders - Anemia, leukopenia, thrombocytopenia - Ventricular fibrillation, hypertension, cardiac arrest, hypersensitivity, seizures, peripheral neuropathy • Contraindications: anemia, hypokalemia, hypomagnesemia. Nephrotoxicity develops in 80% of patients, so use with caution in renal insufficiency. Avoid use with other drugs that cause anemias or electrolyte imbalances • Use in-line filter and deliver 4-6 hours Antiviral Drugs - Prototype: aclovir (zovirax) - Uses: limited to herpes virus such as simplex, zoster, cytomegalovirus, and Epstein-Barr. Nor for HIV. Only effective against actively replicating viruses. Not effective against latent herpes - RoutesL Oral, parenteral, topical - Adverse effects: anorexia, N&V, HA, abdominal pain, confusion, hallucinations, tremors, seizures, coma. May be nephrotoxic. Patient should be well hydrated e nephrotoxic effects. - Contraindications: may be cross-sensitivity with ganciclovir. Use with caution in pregnant and lactating women, renal disease and seizure disorders - Ribavirin (Category X for pregnant women), Amantadine, Rimantadine- other antiviral medications HIV Drugs - Most HIV drugs are metabolized in the liver and have a high hepatotoxicity. Liver function tests should be performed regularly - Most HIV drugs are not absorbed well in the presence of fats. Patients should be instructed to maintain a low fat diet - Most cross the blood-brain barrier. They may have CNS side effects. Especially peripheral neuropathies - HIV drugs may cause bone marrow depression - HIV often becomes resistant to one drug. Drugs are used in combination and are sometimes changed to improve response. T-cell count need to be monitored regularly - HIV drugs do not kill the virus. If they are stopped the virus will resume replication and the disease will progress - Most drugs are very expensive ,often need assistance of medicaid to pay for them - Zidovudine (AZT, ZDV, Retrovir) • Incorporated into DNA triphosphate to stop the building process • Liver, neuropathies Show Less