The document provides an overview of commonly used drugs in pharmacology including antibiotics, antifungals, respiratory drugs, cardiac drugs, corticosteroids, antiemetics/gastrointestinal drugs, anticonvulsants, and insulin. It describes the classes of drugs, their mechanisms of action, clinical uses, and common side effects. The key information covered includes how different antibiotic, antifungal, and respiratory drug classes work, examples of drugs from each class, and their spectrums of activity against bacteria and fungi.
2. Antibiototics
Antibiotics are effective against bacteria and are
considered bacteriostatic or bactericidal. Their
spectrum is determined based on the drugs
effectiveness against different gram negative, gram
positive or acid fast bacteria.
Bacteriostatic- Inhibits or reproduction of bacteria.
Bactericidal- Kills the bacteria.
3. Antibiotics
Penicillins
Works by binding the penicillin binding protein causing cell wall
lysis
Bactericidal
Spectrum primarily gram positive bacteria, beta-lactamase
bacteria are resistant
Most common antibiotic class to cause an allergic reaction
Medications- Ampicillin, Amoxicillin, Penicillin G, Clavamox,
penicillin V, PiperacillinAmpicilla
Carbapenems
Class of beta-lactam antibiotics wide range of antibacterial
activity. Inhibits cell wall synthesis.
Bactericidal
Medications- Imipenem and meropenem
4. Antibiotics
Cephalosporins
Works by interfering with cell wall synthesis by binding to the
penicillin binding protein.
Related to penicillins but also has activity against beta-
lactamase.
Side effects- GI upset, fever, lethargy, tachypnea, pain at
injection site, and nephrotoxicity.
Penetrate soft tissue and fluid very well.
First generation mostly gram positive.
Second generation gram positive and gram negative.
Third generation mainly used against gram negative.
Fourth generation extended spectrum and increased resistance
hydrolysis and beta-lactamase bacteria.
Oral forms- Cephalexin, Cephradine, Cefadroxil, Cefaclor,
cefpodoxime
Parenteral forms- Cefazolin, Cefapirin, Cephaloridine, ceftiofur,
cefoxitin, cefovecin(convenia)
5. Antibiotics
Tetracyclines
Works by inhibiting protein synthesis by binding 30s ribosomal
subunit
Broad spectrum effective against gram positive and gram
negative.
Bacteriostatic
Has antiinflammatory and immunomodulating effects
Side effects- Very commonly causes GI upset, esophageal
strictures in cats, yellowing of teeth and bones when given to
juveniles, hepatotoxic and renal toxic. DO NOT GIVE IV IN
HORSES.
Medications- Doxycycline, Minocycline, tetracycline,
oxytetracycline.
Aminoglycosides
Not readily absorbed through GI tract.
Works by irreversibly binding to 30s ribosomal subunit.
Broad spectrum- most effective against gram negative bacteria.
6. Antibiotics
Fluoroquinolones
Works by inhibiting DNA gyrase which inhibits DNA synthesis.
Broad spectrum effective against gram negative and gram
positive bacteria.
Side effects- GI upset, cartilage deformities in growing animals,
retinal damage in cats.
Medications- Enrofloxacin/Baytril, Marbofloxacin/zeniquin,
Orbifloxicin,
Sulfonamides
Work by Inhibiting folic acid synthesis
Bacteriostatic
Side effects- MULTIPLE SIDE EFFECTS! Vomiting, diarrhea,
anorexia, KCS, bone marrow depression, fever, polyarthritis,
hepatic necrosis, hemolytic anemia, and hypothyroidism.
7. Antibiotics
Macrolides and Lincosamides
Inhibits protein synthesis by binding 50s ribosomal
subunit
Bacteriostatic
Broad spectrum
Medications- Erythromycin, Tylosin, Clindamycin,
Azithromycin.
8. Antifungals
Drugs used to treat fungal(Mycotic) infections
Fungicidal- destroys, kills fungi.
Fungistatic- Having an inhibitory effect on growth or
reproduction of fungi.
Topical- ringworm, yeast
Systemic- Cryptococcosis, Coccidiomycosis,
Histoplasmosis, Blastomycosis.
9. Antifungals
Nystatin
Works by inhibiting membrane permeability.
Fungicidal
Effective for Candida infections in dogs, cats and bird.
Amphotericin B
Used IV ONLY!
Works by disrupting membrane permeability
Fungicidal
Used in systemic fungal infections
10. Antifungals
Ketoconazole
Works by impairing ergosterol synthesis affecting
membrane permeabilty.
Not recommended for use in cats.
Used to treat systemic fungal disease, dermatophytosis
and cushings disease.
Side effects- Hepatotoxic, fever infertility in male dogs
Itraconazole
Works by altering membrane permeability
Fungistatic
Effective in systemic fungal infection. Drug of choice of
blastomycosis
Side effects- Anorexia, hepatotoxicity, vasculitis.
11. Antifungals
Fluconazole
Triazole antifungal
Fungistatic
Alters cellular membrane
Clinical uses- cryptococcus and other systemic fungal
infections.
Side effects- Hepatotoxic, vomiting, diarrhea anorexia.
Flucytosine-
Used with other antifungal drugs
Fungistatic
Inhibits DNA synthesis
Clinical uses- Systemic fungal infection cryptococcus and
candida
Side Effects- GI upset, bone marrow suppression, oral ulcers,
increased liver enzymes.
12. Antifungals
Griseofulvin
Disrupts cell division
Fungistatic
Increased absorption with a fatty meal
Clinical uses- Dermatophytosis
Side effects- hepatotoxic, vomiting and diarrhea. Do not
use in pregnant or breeding animals.
13. Respiratory Drugs
Drugs to treat respiratory disease administered by
oral or parenteral routes
Aerosolization or nebulization allows delivery of high
concentrations of drugs directly into airway.
14. Respiratory drugs
Expectorants-Liquifies and dilutes viscous secretions to
help evacuate secretions.
Used to treat a productive cough
Acts directly on mucus secreting glands, reducing mucus
adhesiveness
Medications- Guaifenesin, iodide preperations and hypertonic
saline
Mucolytics- Decreases viscosity of secretions by altering
chemical composition of mucus
May be nebulized and has few side effects
Medication-Acetylcysteine(also used to treat acetaminophen
toxicity)
Antitussives- Suppresses cough act centrally(Cough
center in brain) or peripherally(Cough receptors in
airways).
Medications- Butorphenol, Hydrocodone, Codeine,
15. Respiratory Drugs
Bronchodilators- Causes bronchodilation
Four categories of drugs that cause bronchodilation
Anticholinergics- used to treat bronchoconstriction associated
with organophosphate or carbamate toxicity.
Glycopyrrolate, atropine
Antihistamines- Blocks effects of histamines used to treat
allergic respiratory conditions
Dyphenhydramine, Cetirizine, Hydroxyzine, Loratadine,
Cyproheptadine
Beta-2 blockers-Combine with receptors on smooth muscle
fibers and relax the muscle
Epinepherine, albuterol, terbutaline
Methylxanthines- Inhibits enzyme in smooth muscle,
phosphodiesterase.
Aminophylline, Theophylline
16. Cardiac Drugs
Positive inotropic drugs- Improve the strength of contraction of heart.
Cardiac glycosides- rarely used due to adverse side effects.
Catecholamines- epinepherine used during cardiac resuscitation and can
be used in anaphylaxis
Inotrope mixed dilator- Pimobendan/vetmedin
Antiarrhythmic drug
Class IA Depresses myocardial excitability, prolong refractory period,
decrease automaticity and increase conduction time
Quinidine and procainamide
Class IB- Stabilizes the myocardial cell membranes. Blocks influx of Na
preventing depolarization.
Lidocaine
Class II Blocks Beta 1 receptor, may block beta 2 receptors also
Propranolol, Atenolol
Class III limited use
Class IV Calcium channel blockers depresses contraction
Diltiazam
17. Cardiac Drugs
Vasodilator drugs- Dilate arteries or veins or both.
Decreases preload and after load on heart. Used to
treat Congestive Heart Failure (CHF).
Hydralazine, Nitroglycerin, Prazosin, Angiotensin-
converting enzyme Inhibitor (ACEI).
Diuretics- Commonly used in treating CHF
Furosemide, Spironolactone (Potassium sparing)
18. Corticosteroids
Mineralocorticoids- Aldosterone controls electrolyte
and water balance.
Produced in zona glomerulosa of adrenal cortex.
Glucocorticoids- Cortisol. Produces anti-
inflammatory and immunosuppresive effects.
Produced in zona fasciculata of adrenal cortex.
Decreased cortisol stimulates hypothalamus to release
corticotropin-releasing factor (CRF) to anterior pituitary
which releases adrenocorticotropic hormone(ACTH)
causing release of cortisol from adrenal cortex.
19. Corticosteroids
Major Effects
Anti-inflammatory effects- By blocking phospholipase,
blocking prostaglandin production.
Prostaglandin major mediator of immune response.
Immunosuppressive effects- Inhibits antibody formation,
decreasing lymphocytes and eosinophils
21. Antiemetics/Gastrointestinal drugs
Antiemetics
Metoclopramide/reglan- Acts centrally on CRTZ center
blocking dopamine.
Increases gastric emptying and Gastroesophageal sphincter
tone.
Ondansteron/zofran and dolasteron/anzemet
Block serotonin receptors on vagal nerve and CRTZ
Used commonly in patients receiving chemotherapy.
Maropitant citrate/cerenia- Blocks binding of substance P
to NK-1 receptors and CRTZ.
Parenteral or oral (Motion sickness)
23. Anticonvulsants
Drugs that prevent or control seizures
Benzodiazapines
Diazepam/valium- Treats seizures in progress 3-4 hours duration.
Can be given rectally to get seizure under control.
Midazolam – Treat seizures in progress, administered IV.
Barbiturates
Pentobarbital- Used to control seizures not responding to
Diazepam. Administered IV.
Phenobarbital- Prevents and treats seizures. Most commonly
used! Administered oral or parenteral. Must regularly check blood
levels and CBC, chemistry panel when administering.
Other
Potassium bromide – Can use alone or in combination with
phenobarbital.
Adjunctive medications- Clorazepate, Gabapentin, Levetircetam,
zonisamide.
24. Insulin
Used to treat Diabetes Mellitus.
Given SC in cases when DKA not present.
DKA cases given as CRI or IM.
Measured in units per milliliters.
U-40 animal approved products (prozinc and vetsulin)
U-100 human approved products
Short acting- Humulin-R, Novolin.
Used in DKA cases IV, IM or SC
Intermediate acting- NPH (Humulin-N), PZI(prozinc).
Used to treat uncomplicated diabetes mellitus, SC only.
Long acting – Glargine(lantus), Detemir(levemir)
Used to treat uncomplicated diabetes mellitus cases, SC.