Histamine & Serotonin Antagonists, NSAIDs, and Cardiovascular Drugs

A set of 50 vocabulary flashcards summarizing key drugs and their primary veterinary uses, mechanisms, or cautions across antihistamine/serotonin agents, NSAIDs, and cardiovascular therapeutics.

First-line treatment for anaphylaxis; a physiological antagonist that rapidly reverses mediator effects such as bronchoconstriction and hypotension.

Epinephrine (Epi)

First-generation H1 antihistamine used for allergies, pruritus, and adjunctive anaphylaxis therapy; notable for sedation.

Diphenhydramine (Benadryl)

Long-acting corticosteroid often included in anaphylaxis protocols for its anti-inflammatory and immunosuppressive effects.

Dexamethasone

Chlorpheniramine

Orally effective first-generation H1 blocker with a 24-hour half-life in dogs; used to reduce pruritus in small animals.

First-generation H1 antihistamine that is a prodrug rapidly converted to cetirizine in dogs; sometimes helps canine pruritus.

Hydroxyzine

Second-generation, non-sedating H1 antihistamine; active metabolite of hydroxyzine; useful for pruritus in cats and mild asthma in people.

Cetirizine (Zyrtec)

Loratadine (Claritin)

Second-generation H1 antagonist; non-sedating due to poor blood–brain barrier penetration.

Fexofenadine (Allegra)

Second-generation H1 blocker largely excluded from CNS; showed promising results for canine pruritus.

Clemastine (Tavist)

Ethanolamine antihistamine with poor oral bioavailability in dogs/horses; occasionally reduces pruritus in cats.

Trimeprazine

Phenothiazine derivative with antihistamine activity; most effective when combined with a corticosteroid such as prednisolone.

Cyproheptadine (Periactin)

5-HT1A antagonist and modest H1 blocker; used for dermatitis, feline appetite stimulation, and treating serotonin syndrome.

Cimetidine

H2 receptor antagonist employed to prevent and treat gastric ulceration.

Famotidine

Potent H2 antagonist widely used for gastric ulcer prevention; longer duration than cimetidine or ranitidine.

Metoclopramide

Prokinetic that acts as a 5-HT4 agonist and weak 5-HT3 antagonist; enhances GI motility and has antiemetic properties.

Compounded 5-HT4 agonist that markedly increases GI motility to manage stasis, reflux, and constipation.

Cisapride

Selective 5-HT3 antagonist used to control moderate to severe vomiting, especially chemotherapy-induced emesis.

Ondansetron

5-HT3 antagonist that serves as an appetite stimulant (notably in cats with CKD) and antiemetic.

Mirtazapine (Remeron)

Ketanserin

5-HT2A antagonist with weak H1 blocking and α-adrenergic blocking effects; used experimentally for vascular and inflammatory conditions.

Opioid analgesic that can trigger non-IgE mast-cell degranulation and histamine release, potentially causing hypotension or pruritus.

Morphine

Fluoxetine (Prozac, Reconcile)

Selective serotonin reuptake inhibitor (SSRI) approved for dogs; treats various behavioral disorders.

Clomipramine (Clomicalm)

Tricyclic antidepressant that blocks 5-HT and norepinephrine reuptake; FDA-approved for canine separation anxiety.

Cytopoint (Lokivetmab)

Canine monoclonal antibody targeting IL-31 to neutralize pruritus and improve atopic dermatitis lesions.

First FDA-approved monoclonal antibody for cats; binds nerve growth factor (NGF) to alleviate osteoarthritis pain.

Solensia (Frunevetmab)

Librela (Bedinvetmab)

Monoclonal antibody that binds canine NGF, providing long-acting analgesia for osteoarthritis pain in dogs.

Selective EP4 prostaglandin receptor antagonist used to treat osteoarthritis pain while sparing kidney and GI tract.

Grapiprant (Galliprant)

Aspirin

Irreversible COX-1 inhibitor (salicylate) used as anti-inflammatory, analgesic, antipyretic, and antithrombotic agent.

Ketoprofen

Nonselective COX inhibitor in dogs/horses and COX-1 selective in cats; used for analgesia and to treat pneumonia in livestock.

Carprofen (Rimadyl)

Moderately COX-2 selective NSAID for canine osteoarthritis and perioperative pain; shows anticancer properties in some tumors.

Flunixin (Banamine)

Potent nonselective NSAID used for equine colic, endotoxemia, and livestock respiratory disease; available in topical swine formulation.

Oxicam NSAID with slight COX-2 selectivity; used for perioperative pain, calf scours, and chronic arthritic or cancer pain.

Meloxicam (Metacam)

Firocoxib (Previcox/Equioxx)

Highly selective COX-2 inhibitor; treats canine OA and equine ocular inflammation, and aids in transitional cell tumor therapy.

Deracoxib (Deramax)

Moderately COX-2 selective NSAID used for pain and inflammation, including management of canine transitional cell tumors.

Misoprostol

Synthetic PGE1 analog administered with NSAIDs to prevent or treat NSAID-induced gastrointestinal ulceration.

Cardiac glycoside that inhibits Na⁺/K⁺-ATPase, increasing intracellular Ca²⁺ to enhance contractility; narrow therapeutic window.

Digoxin (Digitalis)

Pimobendan (Vetmedin)

Inodilator that sensitizes cardiac myofilaments to Ca²⁺ and inhibits PDE III, providing positive inotropy and balanced vasodilation.

Synthetic β1-adrenergic agonist given by CRI for acute systolic heart failure; increases contractility with minimal heart-rate effect.

Dobutamine

Enalapril

ACE inhibitor pivotal in chronic heart-failure management; lowers angiotensin II, reduces remodeling, and improves survival.

Spironolactone

Mineralocorticoid receptor antagonist that counteracts aldosterone-mediated remodeling; weak potassium-sparing diuretic.

Furosemide (Lasix)

Loop diuretic that rapidly relieves pulmonary edema and congestion in CHF; cornerstone of ‘triple therapy’ with ACEI and pimobendan.

Hydralazine

Direct arteriolar vasodilator that lowers afterload, improving stroke volume in volume-overload heart failure.

Diltiazem

Non-dihydropyridine calcium channel blocker that slows AV conduction and aids relaxation in feline HCM.

Dihydropyridine calcium channel blocker; first-choice drug for systemic hypertension in cats due to potent arterial dilation.

Amlodipine

Sildenafil

PDE-5 inhibitor that increases cGMP to dilate pulmonary vessels; mainstay for treating canine pulmonary hypertension.

Carvedilol

Nonselective β-blocker with α1 antagonism and antioxidant effects; lowers heart rate and afterload in chronic heart failure.

Telmisartan (Semintra)

Angiotensin II receptor blocker (ARB) approved for cats; manages hypertension from renal or cardiac disease.

Nitroglycerin

Organic nitrate and venodilator used topically or sublingually for acute heart failure or angina; tolerance develops with chronic use.

Sodium Nitroprusside

Potent mixed vasodilator delivered by CRI for emergent CHF; risk of cyanide toxicity with impaired renal function.