FOP Small animal clinical ems Flashcards
main groups of veterinary antibiotics
aminoglycosides b-lactam antibiotics chloramphenicol fluoroquinolones glycopeptides lincosamides macorlides polymixins rifamycins streptogramins tetracyclines diaminopyrimidines
Aminoglycosides
Inhibition of protein synthesis.
gentamicin tobramycin amikacin streptomycin kanmycin
Bactericidal (dose dependent)
Due to its toxicity, aminoglycoside use has been clinically limited to severe infections.
The more toxic antibiotics in this class have been restricted to topical or oral use for the treatment of infections caused by Enterobacteriaceae.
The less toxic aminoglycosedes are used for parenteral treatment of severe sepsis cause by Gram-negative aerobes.
Nephrotoxic and ototoxic; not effective against anaerobic bacteria.
ß-Lactam Antibiotics
Inhibition of cell wall synthesis
Penicillins
Cephalosporins
Carbapenems
Monobactams
Broad-spectrum: carbapenems, 2nd, 3rd, and 4th generation cephalosporins
Narrow spectrum: penicillin, 1st generation ecphalosporins, monobactams
Generally bactericidal
Ruminants: anthrax, listeriosis, leptospirosis, clostridial and corynebacterial infections; streptococcal mastitis, keratoconjuntivitis
Swine: erysipelas, streptococcal and clostridial infections
Horses: tetanus, strangles, other strep and clostridial infections, foal pneumonia
Dogs and cats: streptococcal and clostridial infections, UTI
chloramphenicol
Inhibition of protein synthesis
Broad spectrum
Bacteriostatic
Because of its capacity to cause fatal aplastic anemia in humans, chloramphenicol is prohibited in food animals in the US and many countries.
May be considered for some anaerobic infections in companion animals, such as serious ocular infections, prostatitis, otitis media/interna and salmonellosis.
Fluoroquinolones
Inhibition of nucleic acid synthesis.
Enrofloxacin, ciprofloxacin, Danofloxacin, Difloxacin, Ibafloxacin, Marbofloxacin, Pradofloxacin, Orbifloxacin
Broad spectrum: 3rd-generation fluoroquinolones
Narrow spectrum: other fluoroquinolones
Bactericidal
Ruminants: acute respiratory disease, infections with E. coli, Salmonella, Mycoplasma, mastitis, metritis, conjuntivitis
Swine: treatment of infections cause by Mycoplasma hyopneumoniae, Actinobaccillus pleuropneumoniae, Escherichia coli, and Pasteurella multocida. Should never be administered in feeds because residues can contaminate the environment; prohibited for use in pigs in some countries.
Horses: for infections with bacteria resistant to the first drug of choice; not recommended in young growing horses (may cause cartilage erosion)
Dogs and cats: prostatitis, mastitits, rhinitis, pyoderma, otitis, wound infections, peritonitis, osteomyelitis, and soft tissue infections; not recommended for use in animals < 8 months of age (or < 18 months of age for large breed dogs to avoid arthropathoc effects).
Glycopeptides
Inhibition of cell wall synthesis
Vancomycin, teicoplanin, avoparcin
Narrow spectrum affecting only Gram-positive bacteria
Bactericidal
Vancomycin: “last resort” drug in human medicine with very few applications in animals.
Avoparcin: used extensively for growth promotion of chickens and pigs.
Lincosamides
Inhibition of protein synthesis.
Lincomycin, Clindamycin, and Pirlimycin
Moderate-spectrum; they are primarily active against Gram-positive bacteria, most anaerobic bacteria, and some mycoplasma.
Can be bactericidal or bacteriostatic, depending on the drug concentration, bacterial species and concentration of bacteria.
General: clindamycin has an excellent activity against anaerobes
Swine: lincomycin is used extensively in the prevention and treatment of dysentery and sometimes in mycoplasma infections
Cattle: used as intramammary infusion in mastitis (pilrimycin)
Horses: should not be used in horses
Dogs and Cats: for infections with Gram-positive cocci and anaerobes
Poultry: for the control of mycoplasmosis (usually in combination with spectinomycin) and necrotic enteritis
Should not be used in horses
Macrolides
Inhibition of protein synthesis.
Erythromycin, Tylosin, Spiramycin, Tilmicosin, Tulathromycin
Narrow spectrum
Generally bacteriostatic, but may be bactericidal at high concentrations or if there is a low number of a highly susceptible bacterial organism.
Erythromycin: drug of choice against Campylobacter jejuni. Can be an alternative to penicillin in penicillin-allergic animals and second choice for anaerobic infections.
Tylosin and spiramycin: used against Mycoplasma infections; used as growth promotants.
Tilmicosin: against Mannheimia, Actinobaciullus, Pasteurella, Mycoplasma.
Polymixins
Inhibition of cell membrane function.
Polymixin B, colistin (Polymixin E)
Narrow spectrum affecting primarily Gram-negative bacteria
Bactericidal
Cattle: colibacillosis and salmonellosis in calves, mastitis
Swine: neonatal porcine colibacillosis
Horses: bacterial keratitis or metritis caused by Klebsiella spp.
Dogs and cats: bacterial keratitis, otitis externa, skin infections
Rifamycins
Inhibition of nucleic acid synthesis.
Rifampin, Rifabutin, Rifapentine
Broad spectrum; also has antiviral and antifungal activity
Streptogramins
Inhibition of protein synthesis.
Virginiamycin
Narrow spectrum; mainly Gram-positive bacteria
Group A or Group B - Bacteriostatic
Group A and Group B - Bacteriocidal
Sulfonamides
Inhibition of other metabolic processes.
Sulfadiazine, sulfamethoxazole, sulfadoxine
Broad-spectrum; affects Gram-positive and many Gram-negative bacteria, toxoplasma and protozoal agents
Bacteriostatic
Tetracyclines
Inhibition of protein synthesis.
Chlortetracycline, oxytetracycline, demethylchlortetracycline, rolitetracycline, limecycline, clomocycline, methacycline, doxycycline, minocycline
Bacteriostatic
Tetracyclines are primarily indicated in the treatment of borreliosis, brucellosis (usually in combination with rifampin or streptomycin), chlamydiosis, ehrlichiosis, leptospirosis, listeriosis, rickettsiosis, and tularemia.
Diaminopyrimidines (Trimethoprim)
Inhibition of other metabolic processes.
Trimethoprim, Aditoprim, Baquiloprim, Ormetoprim
Broad spectrum; affects Gram-positive and many Gram-negative bacteria
Bacteriostatic
main groups of veterinary antiinflamitories
Generally, the classification NSAID is applied to drugs that inhibit one or more steps in the metabolism of arachidonic acid (AA). Unlike corticosteroids, which inhibit numerous pathways, NSAIDs act primarily to reduce the biosynthesis of prostaglandins by inhibiting cyclooxygenase (COX). In general, NSAIDs do not inhibit the formation of 5-lipoxygenase (5-LOX) and hence leukotriene, or the formation of other inflammatory mediators. The novel NSAID tepoxalin is an exception in that it inhibits both COX and 5-LOX.
asprin Acetaminophen (paracetamol) phenylbutazone meclofenamic acid tolfenamic acid flinixixn carprofen ketoprofen etodolac vedaprofen meloxicam deracoxib firocoxib robenacoxib mavacoxib grapiprant dipyrone tepoxalin ibuprophen naproxen
asprin
relief of mild to moderate pain associated with musculoskeletal inflammation or osteoarthritis. The salicylic ester of acetic acid, aspirin (acetylsalicylic acid) is available in several different dosage forms, including bolus (for cattle), oral paste (for horses), oral solution (for poultry), and tablets (for dogs). Enteric-coated products used in human medicine are not recommended in dogs, because gastric retention may lead to erratic plasma exposure
aspirin is not approved for veterinary use, definitive efficacy studies have not been performed to establish effective dosages. Recommended dosages in dogs are 10–40 mg/kg, orally, every 8–12 hours. Aspirin has been used for its anticlotting effect in the treatment of laminitis in horses at a dosage of 10 mg/kg per day, PO. In cats, aspirin may be used for its antiplatelet effects in thromboembolic disease at a dosage of 10 mg/kg, PO, every 48 hours, to allow for prolonged metabolism.
Acetaminophen (paracetamol)
a para-aminophenol derivative with analgesic and antipyretic effects similar to those of aspirin, but it has weaker anti-inflammatory effects than does aspirin and other NSAIDs. The reason for this anomaly is that acetaminophen’s selective COX-2 inhibition is via enzyme reduction; the high levels of peroxides in areas of inflammation are thought to interfere with COX-2 reduction peripherally, whereas the low peroxide levels in the brain and spinal cord account for any centrally mediated analgesia. Acetaminophen does not inhibit neutrophil activation, has little ulcerogenic potential, and has no effect on platelets or bleeding time. The recommended dosage of acetaminophen in dogs is 10–15 mg/kg, PO, every 8 hours. Dose-dependent adverse effects include depression, vomiting, and methemoglobinemia. Acetaminophen has been used in horses; however, the therapeutic range for efficacy and appropriate dose rates are yet to be established. Use in cats is contraindicated because of their deficiency of glucuronyl transferase, which makes them susceptible to methemoglobinemia and centrilobular hepatic necrosis.
Acetaminophen in combination with codeine has been used in dogs. The efficacy of oral codeine is weak, because very little is converted to morphine in this species, which queries the benefit of using the acetaminophen-codeine combination. In fixed combination formulations, the ability for the veterinarian to independently make dose adjustments of each constituent drug is prevented; increasing the dose of codeine in pursuit of improved analgesia may cause acetaminophen toxicity.
Phenylbutazone
One of the earliest NSAIDs approved for use in horses and dogs, phenylbutazone (PBZ) is a pyrazolone derivative available in tablet, paste, gel, and parenteral formulations. When administered orally PBZ adsorbs to hay in the diet, to then be released during fermentation in the hindgut. Although this potentially may reduce gastrointestinal absorption and bioavailability, the clinically relevant effect is a delay in absorption. Once PBZ is absorbed, binding to plasma proteins is high (99% in horses). PBZ is metabolized by the liver to several active (oxyphenbutazone) and inactive metabolites, which are excreted in urine.
One of the major therapeutic uses of PBZ is to treat acute laminitis in horses. Laminitis is treated initially with injectable PBZ at dosages up to 8.8 mg/kg, followed by treatment at 2.2–4.4 mg/kg, PO, every 12 hours. Because the therapeutic index for PBZ is relatively narrow (PBZ exhibits zero order metabolism), the dosage should be adjusted to the minimum possible to maintain comfort and avoid toxicity
Meclofenamic Acid
Meclofenamic acid is a fenemate (anthranilic acid) NSAID available for horses as a granular preparation and for dogs as an oral tablet. The recommended dosage in horses is 2.2 mg/kg per day for 5–7 days; the recommended dosage in dogs is 1.1 mg/kg per day for 5–7 days. In cattle, administration of meclofenamic acid results in a biphasic pattern of absorption, with an initial peak plasma concentration reached at ~30 minutes and a secondary peak 4 hours after dosing. In horses, meclofenamic acid is rapidly absorbed, but feeding before dosing may delay absorption. The onset of action is slow, requiring 2–4 days of dosing for a clinical effect. Although it is effective in the treatment of chronic laminitis, meclofenamic acid has a therapeutic index that may be lower than that of other NSAIDs.
