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.

1. Pharmacology Review
Commonly Used Drugs

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

20. Corticosteroids
 Clinical uses
 Anti-inflammatory
 Allergic reactions
 Autoimmune disease
 Shock
 Addison’s disease
 Some types of cancers
 Side effects- PU/PD, Polyphagia, thinning of skin,
muscle wasting gastric ulcers, delayed healing,
Iatrogenic cushing’s.
 Injectable products- Dexamethasone, Depo-medrol,
Triamcinalone.
 Oral products- Prednisone/prednisolone, Temaril-P.

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)

22. Antiemetics/Gastrointestinal drugs
 Gastrointestinal medications
 H2 antagonist- Cimetidine, ranitidine, Famotidine.
 Proton pump inhibitors- Omeprazole
 Antacids- Maalox and Mylanta
 Gastromucosal protectants – Sucralfate/Carafate
 Metronidazole/flagyl- Synthetic
antibacterial/antiprotazoal.
 Used to treat giardia, trichomonas, IBD, Ulcerative colitis
and anaerobic infections.

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.