Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Antibiotics
Patient Management
| Question | Answer |
|---|---|
| Define the term bactericidal and give examples | Bacterialcidal drugs- kill organisms so the number of viable organisms falls rapidly after exposure (PCN & Streptomycins) |
| Define the term bacteriostatic and give examples | Bacterialstatic drugs- inhibits the growth of bacteria but does not kill them (Sulfonamides & Tetracyclines) |
| Define the term minimum inhibitory concentration (MIC) | lowest concentration of a drug that inhibits bacterial growth |
| Describe the major mechanisms of microbial resistance to antibiotic drugs | Inactivation of the drug by microbial enzymes, decreased accumulation of the drug by the microbe, reduced affinity of the target macromolecule for the drug |
| Cite examples of host factors that can affect selection of an antimicrobial agent. | pregnancy,drug allergies,age, immune status (impairment), presence of renal impairment, hepatic insufficiency, abscesses, indwelling catheters & similar devices |
| Identify sites of infection not readily penetrated by many antimicrobial drugs | central nervous system, bone, prostate gland, ocular tissues. |
| Describe situations in which combination drug therapy with antibiotics is preferable to monotherapy | If 2 bactericidal drugs that act by 2 different mechanisms are given in combination, they tend to exhibit additive or synergistic effects against susceptible bacteria. Mixed infections are usually treated with more than one drug. |
| Identify examples where prophylactic use of antibiotics is recommended. | Used in some cases to reduce the incidence of infections associated with surgical and other invasive procedures, or to prevent disease transmission to close contacts of infected persons. |
| Identify why inhibition of cell wall synthesis by antimicrobial drugs is usually bactericidal. | Without a cell wall, the bacterium is unprotected. Because a cell wall is not found in higher organisms, antimicrobial drugs can inhibit its formation without harming host cells. |
| Name the three most commonly used beta-lactam antibiotics. | PCN, beta-lactamase inhibitors, and cephalosporins. |
| Narrow-Spectrum Penicillins | Penicillin G & Penicillin V |
| Penicillinase-Resistant Penicillins | Dicloxacillin & Nafcillin |
| Extended-Spectrum Penicillins | Amoxicillin, Ampicillin, Piperacillin, & Ticarcillin |
| Penicillin G | used to treat group A strep infections and syphilis. Active against Clostridium perfrigens. Most staph and gonocci, and some strains of pneumoococci are now resistant to pen G. Given IM and orally |
| Penicillin V | Used to treat Pharyngitis. Given orally. |
| procaine penicillin G | hydrolyzed more rapidly and produces a significant plasma concentration of pencillin for about 24 hrs |
| benzathine penicillin G | hydrolyzed slowly over a period of several weeks and provides low plasma concentrations for an extended period of time |
| Typical infections that are treated by procaine and benzathine PCN G | streptococci, meningococci, spirochetes |
| Identify the three primary mechanisms by which bacteria exert resistance to PCN and other beta-lactam antibiotics. | inactivation of the drugs by B-lactamase enzymes, reduced affinity of PBP for the antibiotics, decreased entry of the drugs into bacteria through outer membrane porins |
| Describe the major adverse effects of penicillins. | drug induced hypersensitivity reactions mediated by IgE leading to seizure, hives, anaphylactic shock, serum sickness, hepatitis, skin rashes |
| Describe the rationale for use of a beta-lactamase inhibitor with a beta lactam antibiotic. (representative example: amoxicillin plus clavulanate) | to act as a suicide inhibitor of the BLM enzymes by serving as a surrogate substrate for them. (the Beta lactamase is tied up so the pcn can't be inactivated) |
| First generation cephalosporins are primarily active against? | gram positive cocci and a limited number of gram negative bacilli. |
| cephalexin | 1st generation, primarily used for skin and soft tissue infections caused by gram positive cocci and to treat uncomplicated UTIs. |
| cefuroxime axetil | 2nd gen, tx otitis media when caused by H influenzae strains. |
| ceftriaxone | 3rd gen, single dose regiment for gonorrhea, otitis media, pneumonia, meningitis, intra-abdominal or UTI, and advanced Lyme dz. |
| cefepime | 4th gen, intra-abdominal and UTI infections and pneumonia |
| Describe the issue of cross-sensitivity between cephalosporins and penicillins. | cephalosporins ehibit some cross-sensitivity with penicillins, and about 5% of persons allergic to pcn will also be allergic to cephalosporins. |
| Uses of vancomycin. | active against some strains of MRSA, usually the first choice in treating skin and soft tissue infections, streptococcal and enterococcal infections caused by PCN resistant organisms, including endocarditis and NECROTIZING FASCIITIS! |
| Major clinical use of aminoglycosides | aerobic gram-negitive bacilli, prophylaxis and treatment of serious infections |
| Route of admin for aminoglycosides | IV, topical, IM, Oral - occassionally |
| Major adverse effects of aminoglycosides | nephrotoxicity & otoxicity |
| Describe the clinical use of neomycin in triple-antibiotic topical preparations. | limited to topical superfical infections due to its nephrotoxicity |
| Major clinical use of tetracyclines | broadspectrum, bacteriostatic that ingibit the growth of gram-positive and gram-negative organisms, rickettsiae, spirochetes, mycoplasmas, and chlamdiae. |
| Bacterial resistance to tetracyclines is caused by what? | the transmission of plasmids containing resistance factors by bacterial conjugation, altered bactericidal porins that prevent bacterial uptake of the drugs, drug efflux, altered target binding, enzymatic inactivation |
| Adverse Effects of tetracyclines | use in pregnant women or children under the age of 8 can cause discoloration of the teeth & hypoplasia of the enamel, nephrotoxicity, use with aminoglycosides potentiates nephrotoxicity, hepatotoxicity: fatty degeneration, photosensitivity |
| Major clinical use of macrolides | active against Upper Respiratory Tract Infections and Pneumonia, group A streptocicci, pneumococci, chlamydiae, M. pneumoniae, legionella pneumophila |
| Bacterial resistance against macrolides is caused by what | decrease binding to the 50S ribosomal subunit, enzymatic inactivation, increased bacterial efflux |
| Adverse Effects of macrolides | stomatitis, heartburn, nausea, anorexia, abdominal discomfort, diarrhea, tinnitis, impaired hearing |
| Major clinical use of ketolides | sinusitis, bronchitis, community-acquired pneumonia, Streptococcus pneumoniae, Legionella, Chlamydia, H. influenza, M. catarrhalis |
| Adverse Effects of ketolides | diarrhea, nausea, prolongs QT intervals (avoid taking with antiarrhythmic drugs), increased weakness in those with myasthesia gravis, impair visual accommodation |
| Major Clinical Use of clindamycin | Active against gram-positive cocci, useful in treating infections caused by gram –positive cocci and anaerobes that are resistant to penicillin and other drugs |
| Adverse effects of clindamycin | Causes a higher incidence of pseudomembranous colitis than do other antibiotics. |
| Describe the major clinical uses of mupirocin. | Active against streptococci and staphylococci, administered topically to treat impetigo and to eradicate nasal carriers of methicillin-resistant staphylococci. |
| Major clinical uses of sulfonamides | prevent or treat UTIs, inhibit dihydropteroate synthase & the synthesis of dihydrofolate, thus inhibiting bacterial folic acid synthesis, 1st drug to treat systemic bacterial infections…now significant resistance has developed in many bacterial species. |
| Adverse effects of Sulfonamides | mild skin rashes, erythema multiform, Stevens-Johnson syndrome, crystalluria, GI reactions, headaches, hepatitis, and heatopoietic toxicity. In persons with glucose-6-phosphate dehydrogenase deficiency, sufonamides can cause hemolytic anemia. |
| Major clinical uses of Folate Reductase Inhibitors = trimethoprim | bacterial prostatitis and vaginitis. |
| Adverse effects of folate reductase inhibitors | nausea, vomiting, epigastric distress, rashes, hepatitis, thrombocytopenia, leucopenia, and other hematologic disorders |
| Major clinical uses of trimethoprim-sulfamethoxazole (TMP-SMX) | UTIs, upper respiratory tract infections, and infections caused by P. carinii or N. asteroids. |
| Adverse effects of trimethoprim-sulfamethoxazole (TMP-SMX) | megaloblastic anemia in pts who have a low dietary intake of folic acid(uncommon), nausea, vomiting,thrombocytopenia, leucopenia, mild skin rashes, erythema multiform, Stevens-Johnson syndrome, crystalluria, headaches, hepatitis & heatopoietic toxicity |
| Major clinical use of fluoroquinolones | UTIs, GI infections, bone and joint infections, skin infections, and anthrax exposure. Advanced fluoroquinolones, like levofoxacin, are also used to treat community-acquired pneumonia. |
| Adverse effects of fluoroquinolones | tendonitis & rupture, arthropathy, osteochondrosis(reasons NOT to prescribe to children), hypo/hyperglycemia, seizures, phototoxicity, prolongation of the QT interval, inhibits the metabolism of caffeine, so advise pts. to reduce caffeine intake. |
| Major clinical use of nitrofurantoin, including the preferred formulation. | uncomplicated UTIs. |
| Describe the major clinical uses of isoniazid | Isoniazid: inhibits synthesis of cell wall component of TB, effective at attacking both quickly growing bacterial colonies & persistent slow-growing ones. |
| Major clinical uses of rifampin | broad-spectrum antibiotic (gram+/- & acid fast bacilli) prevents DNA transcription, 1st line in TB, prophylacticly for exposure to neisseria meningitidis, haemophilus influenzae B, leprosy, tubercular meningitis, staph endocarditis, legionella infections |
| Resistance to isoniazid | mutations of the katG gene resulting in loss of catalase-peroxidase enzyme required for activation of isoniazid in bacteria |
| Adverse Effects of isoniazid | Hepatitis, peripheral neuritis: paresthesia, toxic encephalopathy or seizures, granulocytosis, anemia, thrombocytopenia |
| Resistance to Rifampin | Never used alone because of liklihood that TB will develop resistance during course of therapy |
| Adverse Effects to rifampin | impaired liver function,hepatitis, hypersensitivity reaction, renal dz, leukopenia, thrombocytopenia, discolored saliva, tears, urine, Cytochrome P450 isozyme inducer-->accelerates metabolism of other drugs, reduces serum concentration & effectiveness |
| Systemic mycoses | present with sx of soft tissue infection, UTI, PNA, meningitis, septicemia. chronic and indolent, invasive or life threatening. Cause aspergillus, blastomyces, candida (*more common in immunocompromised) |
| Subcutaneous mycoses | puncture wounds contaminated with soil fungi (Ex. sporotrichosis) |
| Superficial mycoses | infections of nails, skin, mucous membranes usually caused by dermatophytes or yeasts, candida albicans, tinea pedia (athlete's foot), tinea corporis/ capitis (ringworm), tinea cruris (jock itch).Presents with rash, pruritis, erythema |
| Major clinical uses of amphotericin B | systemic/ subcutaneous mycoses and superficial candida |
| Major toxicities of amphotericin B | VERY renal toxic --> hypokalemia/ hypomagnesemia, azotemia, MUST monitor electrolytes weekly, acute liver failure, cardiac arrhythmias |
| Describe the major clinical uses of nystatin. | Trx of Candida infection - usually as a cream, powder, lozenge, tablets and suspensions, vaginal tablets |
| Fluconazole: | (1) fungal (cryptococcal) meningitis in pt w AIDS (only one that penetrates CSF), (2) candidiasis (disseminated, urinary, or vaginal) |
| Voriconazole: | effective against aspergillus and candida |
| Adverse effects of voriconazole: | (1) visual disturbances (light and color), photophobia...usually mild and transitory, (2) elevated alanine and aspartate aminotransferase (few, but can cause death)....need to monitor |
| Clotrimazole: | (1) topical for candida of mouth, throat, vagina, vulva, (2) dermatophyte infections |
| Adverse Effects of azole derivatives | Rash,elevated hepatic enzymes, hepatic injury, hematopoeitic toxicity, GI distress (N/V/D), inhibit cytochrome P450 so doses of drugs such as benzos or warfarin may have to be adjusted |
| Major clinical use of terbinafine. | Trx of superficial dermatophyte and candida |
| EX. onychomycosis (6 weeks for fingernails, 12 weeks for toenails) - daily oral trx | |
| Major clinical uses of acyclovir, famciclovir, and valacyclovir. | herpesvirus infections(HSV), varicella-zoster virus (VZV) and cytomegalovirus (CMV). |
| Clinical use of oseltamivir and zanamivir in the prevention and treatment of influenza. | Active against pretty much all strains, including A, B, & the avian flu (H5N1). Oseltamivir can be used as prophylaxis or treatment of pts. > 1, decreasing symptom severity. Zanamivir is a nasal spray for pts. > 7. |
| Clinical use of lamivudine for treatment of hepatitis B infection. | This inhibits hep B replication and is the first orally effective drug for hep B pts. It's also used for HIV. Acts on the reverse transcription of intermediate RNA of hep B. |
| Primary clinical use of ribavirin | broad-spectrum antiviral. adenovirus,colorado tick fever v,crimean-congo hemorrhagic fever v,Hantaan v,hep A and C,herpesvirus,flu A and B,Lassa v,measles,Muerto Canyon fever v,mumps,respiratory syncytial v,Rift Valley fever v & yellow fever v |
| Adverse effects of ribavirin | By inhalation can cause serious pulmonary and cardiovascular effects like apnea, pheumothorax and cardiac arrest. By IV can cause seizures. |
| Major clinical uses ofinterferon-alfa. | hepatitis viruses,some papillomaviruses, mainly used in treatment of hep B, C, non-A, non-B or non-C, genital warts, hairy cell leukemia, Kaposi's sarcoma, renal carcinoma, malignant melanoma and multiple myeloma. |
| Adverse effects of interferon-alfa. | causes hematologic toxicity, cardiac arrythmias, changes in BP, central nervous dysfunction, GI distress, chills, fatigue, headache and myalgia. |
| Major clinical uses of metronidazole | (Flagyl)anaerobic protozoa that cause infection such as Entamoeba histolytica, Giardia intestinalis, Trichamonas vaginalis and Balantidium coli. Also active against some bacterias. Drug of choice for amebiasis, giardiasis, and trichomoniasis. |
| Adverse effects and interactions with metronidazole (Flagyl) | some GI discomfort, possible N/V, a metallic taste and transient leukopenia or thrombocytopenia. Also increases the anticoagulant effect of warfarin, and causes a disulfiram-like reaction? with ethanol so pts. should avoid alcohol |
| Major clinical use of permethrin | For ectoparasites (lice and mites) Permethrin is the treatment of choice for these infestations. Available in liquid form for hair and scalp treatment, cream for scabies. |
Created by:
cljgle
Popular Pharmacology sets