Table: Commonly Used Cardiovascular Drugs and Dosages-MSD Veterinary Manual

Commonly Used Cardiovascular Drugs and Dosages

Drug	Dosage
Amiodarone	Dog: 8–10 mg/kg, PO, q 12–24 h for 7–10 days, then decrease to 4–6 mg/kg, q 24 h for longterm treatment Horse: 5 mg/kg/h, IV, for 1 h, then 0.83 mg/kg/h for 23 h, then 1.9 mg/kg/h for 30 h or to effect; or 10 mg/kg, PO, q 24 h
Amlodipine	Dog: 0.1–0.2 mg/kg, PO, q 12 h; or 0.2–0.4 mg/kg, PO, q 24 h
	Cat: 0.625–1.25 mg/cat, PO, q 12–24 h
Aspirin (antiplatelet dosage)	Dogs: 0.5–10 mg/kg, PO, q 24 h, long-term^a
	Horse: 10 mg/kg, PO, q 24 h (bacterial endocarditis)
	Cow: 100 mg/kg, PO, q 24 h (bacterial endocarditis)
Atenolol	Dog: 0.2–1 mg/kg, PO, q 12 h
	Cat: 1–2.5 mg/kg, PO, q 12 h; or 6.25–12.5 mg/cat, PO, q 12 h
Benazepril	Dog: 0.25–0.5 mg/kg, PO, q 12–24 h
	Cat: 0.25–0.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, PO, q 24 h
	Horse: 0.5–1 mg/kg, PO, q 12–24 h
Captopril	Dog: 0.5–2 mg/kg, PO, q 8 h Cat: 3.125–6.25 mg/cat, PO, q 8–12 h
Clopidogrel	Dog: loading dose for rapid onset of action (90 min) 10 mg/kg, PO (once); 1–2 mg/kg, PO, q 24 h, longterm
	Cat: 18.75 mg/cat, PO, q 24 h
Digoxin	Dog: 0.003–0.011 mg/kg, PO, q 12 h (round down to limit risk of toxicosis) Horse: 2.2–3.75 mcg/kg, IV, q 12 h; or 11–17.5 mcg/kg, PO, q 12 h (loading dose reported but rarely used)
	Cow: loading dose of 22 mcg/kg, IV, followed by CRI^a of 0.86 mcg/kg/h; or 11 mcg/kg, IV, q 8 h
Diltiazem	Dog: 0.5–2.5 mg/kg, PO, q 8 h (immediate release formulation); 1–4 mg/kg, PO, q 12 h (sustained release formulations)
	Cat: 7.5 mg/cat, PO, q 8 h (immediate release formulation); 30–60 mg/cat, PO, q 12–24 h (sustained release formulation) Horse: 0.125 mg/kg, slow IV, every 10 min up to a maximum dose of 1.25 mg/kg, IV
Dobutamine	Dog: 2.5–15 mcg/kg/min, CRI^a Horse: 1–5 mcg/kg/min, CRI^a
Enalapril	Dog: 0.25–0.5 mg/kg, PO, q 12 h
	Cat: 0.25–0.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, PO, q 24 h
Furosemide	Dog: 2–4 mg/kg, IV, IM, SC, every 1–6 h; 0.25–1 mg/kg/h, CRI^a; or 1–6 mg/kg, PO, q 8–12 h
	Cat: 0.5–2 mg/kg, IV, IM, SC, every 1–8 h; 0.25–0.6 mg/kg/h, CRI^a; or 1–2 mg/kg, PO, q 12–24 h (maximum PO daily dose of 12 mg/kg)
	Horse: 1–3 mg/kg, IV, IM, q 6–8 h; or 1–2 mg/kg, IV, loading dose, followed by 0.12 mg/kg/h, CRI^a; or for chronic diuresis, 0.5–2 mg/kg, PO or IM, q 8–12 h Cow: 500 mg/animal, q 24 h; or 250 mg/animal, IM or IV, q 12 h
Hydralazine	Dog: 0.5–3 mg/kg, PO, q 12 h
	Horse: 120 mg/horse, PO, q 24 h, q 12 h; or 0.5–1.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, IV, q 4 h
Hydrochlorothiazide	Dog: 2–4 mg/kg, PO, q 12 h Cat: 0.5–2 mg/kg, PO, q 12-24 h
Lidocaine	Dog: 2–4 mg/kg, IV bolus as a loading dose followed by 25–75 mcg/kg/min, IV as a CRI^b
	Horse: 0.25–0.5 mg/kg, slow IV, every 5–15 min; repeat up to a total of 2.0 mg/kg, IV, in conscious horse; or 1.3 mg/kg loading, then 50 mcg/kg/min, CRI^a
	Cow: 0.5 mg/kg, slow IV, every 10–15 min
Magnesium sulphate	Horse: 2–5 mg/kg, slow IV, every 2 min, repeat up to a total dose of 50 mg/kg
Mexiletine	Dog: 4–6 mg/kg, PO, q 8 h
Nitroglycerin ointment 2%	Dog: 4–12 mg, topically, q 12 h (maximum dose, 15 mg/dog) (remove after 6 h to provide a nitrate-free interval)
	Cat: 2–4 mg/cat, topically, q 6–8 h for 1–2 days
Pimobendan	Dog, cat: 0.4–0.6 mg/kg, PO, q 24 h, divided q 12 h (doses do not need to be equal in am and pm for chronic dosing; frequency may be increased to 0.75–0.9 mg/kg, PO, q 24 h, divided q 8–12 h)
Procainamide	Dog: 4–6 mg/kg, PO, every 2–4 h ( immediate release formulation); 10–20 mg/kg, PO, q 8 h (sustained release formulation); 2–25 mg/kg, slow IV bolus to effect, or CRI^a at 25–40 mcg/kg/min
	Horse: 1 mg/kg/min, IV, maximum of 20 mg/kg, IV; or 25–35 mg/kg, PO, q 8 h
Propanolol	Horse: 0.03–0.1 mg/kg, IV; or 0.38–0.78 mg/kg, PO, q 8 h
Quinidine sulfate	Dog: 5–10 mg/kg, IV, q 6 h; or 6–20 mg/kg, PO, q 6–8 h
	Horse: 22 mg/kg, via nasogastric tube, q 2 h until converted, usually 4–6 doses, not to exceed total dose of 132 mg/kg
	Cow: 48 mg/kg, infused IV over 4 h
Quinidine gluconate	Dog: 6–20 mg/kg, IM, q 6 h; or 6–20 mg/kg, PO, q 6–8 h
	Horse: 2.2 mg/kg, IV, q 10 min, not to exceed total dose of 12 mg/kg, IV
Sildenafil	Dog: 1–3 mg/kg, PO, q 8–12 h Cat: 1–2 mg/kg, PO, q 12 h
Sotalol	Dog, cat: 1–2.5 mg/kg, PO, q 12 h Horse: 2–3 mg/kg, PO, q 12 h
Spironolactone	Dog: 1–2 mg/kg, PO, q 12 h; or 2 mg/kg, PO, q 24 h Horse: 2–4 mg/kg, PO, q 24 h
	Cat: 1–2 mg/kg, PO, q 12–24 h
Tadalafil	Dog: 1–2 mg/kg, PO, q 24 h
Telmisartan	Dog: 1 mg/kg, PO, q 24 h Cat: 1.5 mg/kg, PO, q 12 h for 14 days, then 2 mg/kg, PO, q 24 h
Torsemide	Dog: 0.1–0.4 mg/kg, PO, q 12–24 h Cat: 0.05–0.25 mg/kg, PO, q 12–24 h; or 1.25 mg/cat, PO, q 12–24 h
^aUltralow doses of 0.5 mg/kg PO q 24 h of aspirin have been found effective at reducing platelet counts in dogs.(1) The recommended dose of aspirin in dogs starts at a low dose (1–2 mg/kg PO q 24 h) moving up to a high dose (10 mg/kg PO q 24 h).(2) However, low-dose aspirin does not consistently inhibit platelet function in every dog so its clinical efficacy has been questioned.(2) Doses of 10 mg/kg are used for analgesia.(3). References 1. Weinkle TK, Center SA, Randolph JF, Warner KL, Barr SC, Erb HN. Evaluation of prognostic factors, survival rates, and treatment protocols for immune-mediated hemolytic anemia in dogs: 151 cases (1993-2002). J Am Vet Med Assoc. 2005;226(11):1869–1880. doi:10.2460/javma.2005.226.1869. 2. Dudley A, Thomason J, Fritz S, et al. Cyclooxygenase expression and platelet function in healthy dogs receiving low-dose aspirin. J Vet Intern Med. 2013;27(1):141–149. 3. Mathews K, Bennett D. Nonsteroidal Anti-Inflammatory Analgesics. In: Ettinger SJ, Feldman EC, eds. Textbook of veterinary internal medicine: diseases of the dog and the cat. 7th ed. St. Louis, Mo: Elsevier Saunders; 2010:608–615. ^b CRI = constant-rate infusion

Drug

Dosage

Amiodarone

Dog: 8–10 mg/kg, PO, q 12–24 h for 7–10 days, then decrease to 4–6 mg/kg, q 24 h for longterm treatment

Horse: 5 mg/kg/h, IV, for 1 h, then 0.83 mg/kg/h for 23 h, then 1.9 mg/kg/h for 30 h or to effect; or 10 mg/kg, PO, q 24 h

Amlodipine

Dog: 0.1–0.2 mg/kg, PO, q 12 h; or 0.2–0.4 mg/kg, PO, q 24 h

Cat: 0.625–1.25 mg/cat, PO, q 12–24 h

Aspirin (antiplatelet dosage)

Dogs: 0.5–10 mg/kg, PO, q 24 h, long-term^a

Horse: 10 mg/kg, PO, q 24 h (bacterial endocarditis)

Cow: 100 mg/kg, PO, q 24 h (bacterial endocarditis)

Atenolol

Dog: 0.2–1 mg/kg, PO, q 12 h

Cat: 1–2.5 mg/kg, PO, q 12 h; or 6.25–12.5 mg/cat, PO, q 12 h

Benazepril

Dog: 0.25–0.5 mg/kg, PO, q 12–24 h

Cat: 0.25–0.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, PO, q 24 h

Horse: 0.5–1 mg/kg, PO, q 12–24 h

Captopril

Dog: 0.5–2 mg/kg, PO, q 8 h

Cat: 3.125–6.25 mg/cat, PO, q 8–12 h

Clopidogrel

Dog: loading dose for rapid onset of action (90 min) 10 mg/kg, PO (once); 1–2 mg/kg, PO, q 24 h, longterm

Cat: 18.75 mg/cat, PO, q 24 h

Digoxin

Dog: 0.003–0.011 mg/kg, PO, q 12 h (round down to limit risk of toxicosis)

Horse: 2.2–3.75 mcg/kg, IV, q 12 h; or 11–17.5 mcg/kg, PO, q 12 h (loading dose reported but rarely used)

Cow: loading dose of 22 mcg/kg, IV, followed by CRI^a of 0.86 mcg/kg/h; or 11 mcg/kg, IV, q 8 h

Diltiazem

Dog: 0.5–2.5 mg/kg, PO, q 8 h (immediate release formulation); 1–4 mg/kg, PO, q 12 h (sustained release formulations)

Cat: 7.5 mg/cat, PO, q 8 h (immediate release formulation); 30–60 mg/cat, PO, q 12–24 h (sustained release formulation)

Horse: 0.125 mg/kg, slow IV, every 10 min up to a maximum dose of 1.25 mg/kg, IV

Dobutamine

Dog: 2.5–15 mcg/kg/min, CRI^a

Horse: 1–5 mcg/kg/min, CRI^a

Enalapril

Dog: 0.25–0.5 mg/kg, PO, q 12 h

Cat: 0.25–0.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, PO, q 24 h

Furosemide

Dog: 2–4 mg/kg, IV, IM, SC, every 1–6 h; 0.25–1 mg/kg/h, CRI^a; or 1–6 mg/kg, PO, q 8–12 h

Cat: 0.5–2 mg/kg, IV, IM, SC, every 1–8 h; 0.25–0.6 mg/kg/h, CRI^a; or 1–2 mg/kg, PO, q 12–24 h (maximum PO daily dose of 12 mg/kg)

Horse: 1–3 mg/kg, IV, IM, q 6–8 h; or 1–2 mg/kg, IV, loading dose, followed by 0.12 mg/kg/h, CRI^a; or for chronic diuresis, 0.5–2 mg/kg, PO or IM, q 8–12 h

Cow: 500 mg/animal, q 24 h; or 250 mg/animal, IM or IV, q 12 h

Hydralazine

Dog: 0.5–3 mg/kg, PO, q 12 h

Horse: 120 mg/horse, PO, q 24 h, q 12 h; or 0.5–1.5 mg/kg, PO, q 12 h; or 0.5 mg/kg, IV, q 4 h

Hydrochlorothiazide

Dog: 2–4 mg/kg, PO, q 12 h

Cat: 0.5–2 mg/kg, PO, q 12-24 h

Lidocaine

Dog: 2–4 mg/kg, IV bolus as a loading dose followed by 25–75 mcg/kg/min, IV as a CRI^b

Horse: 0.25–0.5 mg/kg, slow IV, every 5–15 min; repeat up to a total of 2.0 mg/kg, IV, in conscious horse; or 1.3 mg/kg loading, then 50 mcg/kg/min, CRI^a

Cow: 0.5 mg/kg, slow IV, every 10–15 min

Magnesium sulphate

Horse: 2–5 mg/kg, slow IV, every 2 min, repeat up to a total dose of 50 mg/kg

Mexiletine

Dog: 4–6 mg/kg, PO, q 8 h

Nitroglycerin ointment 2%

Dog: 4–12 mg, topically, q 12 h (maximum dose, 15 mg/dog) (remove after 6 h to provide a nitrate-free interval)

Cat: 2–4 mg/cat, topically, q 6–8 h for 1–2 days

Pimobendan

Dog, cat: 0.4–0.6 mg/kg, PO, q 24 h, divided q 12 h (doses do not need to be equal in am and pm for chronic dosing; frequency may be increased to 0.75–0.9 mg/kg, PO, q 24 h, divided q 8–12 h)

Procainamide

Dog: 4–6 mg/kg, PO, every 2–4 h ( immediate release formulation); 10–20 mg/kg, PO, q 8 h (sustained release formulation); 2–25 mg/kg, slow IV bolus to effect, or CRI^a at 25–40 mcg/kg/min

Horse: 1 mg/kg/min, IV, maximum of 20 mg/kg, IV; or 25–35 mg/kg, PO, q 8 h

Propanolol

Horse: 0.03–0.1 mg/kg, IV; or 0.38–0.78 mg/kg, PO, q 8 h

Quinidine sulfate

Dog: 5–10 mg/kg, IV, q 6 h; or 6–20 mg/kg, PO, q 6–8 h

Horse: 22 mg/kg, via nasogastric tube, q 2 h until converted, usually 4–6 doses, not to exceed total dose of 132 mg/kg

Cow: 48 mg/kg, infused IV over 4 h

Quinidine gluconate

Dog: 6–20 mg/kg, IM, q 6 h; or 6–20 mg/kg, PO, q 6–8 h

Horse: 2.2 mg/kg, IV, q 10 min, not to exceed total dose of 12 mg/kg, IV

Sildenafil

Dog: 1–3 mg/kg, PO, q 8–12 h

Cat: 1–2 mg/kg, PO, q 12 h

Sotalol

Dog, cat: 1–2.5 mg/kg, PO, q 12 h

Horse: 2–3 mg/kg, PO, q 12 h

Spironolactone

Dog: 1–2 mg/kg, PO, q 12 h; or 2 mg/kg, PO, q 24 h

Horse: 2–4 mg/kg, PO, q 24 h

Cat: 1–2 mg/kg, PO, q 12–24 h

Tadalafil

Dog: 1–2 mg/kg, PO, q 24 h

Telmisartan

Dog: 1 mg/kg, PO, q 24 h

Cat: 1.5 mg/kg, PO, q 12 h for 14 days, then 2 mg/kg, PO, q 24 h

Torsemide

Dog: 0.1–0.4 mg/kg, PO, q 12–24 h

Cat: 0.05–0.25 mg/kg, PO, q 12–24 h; or 1.25 mg/cat, PO, q 12–24 h

^aUltralow doses of 0.5 mg/kg PO q 24 h of aspirin have been found effective at reducing platelet counts in dogs.(1) The recommended dose of aspirin in dogs starts at a low dose (1–2 mg/kg PO q 24 h) moving up to a high dose (10 mg/kg PO q 24 h).(2) However, low-dose aspirin does not consistently inhibit platelet function in every dog so its clinical efficacy has been questioned.(2) Doses of 10 mg/kg are used for analgesia.(3).

References

1. Weinkle TK, Center SA, Randolph JF, Warner KL, Barr SC, Erb HN. Evaluation of prognostic factors, survival rates, and treatment protocols for immune-mediated hemolytic anemia in dogs: 151 cases (1993-2002). J Am Vet Med Assoc. 2005;226(11):1869–1880. doi:10.2460/javma.2005.226.1869.

2. Dudley A, Thomason J, Fritz S, et al. Cyclooxygenase expression and platelet function in healthy dogs receiving low-dose aspirin. J Vet Intern Med. 2013;27(1):141–149.

3. Mathews K, Bennett D. Nonsteroidal Anti-Inflammatory Analgesics. In: Ettinger SJ, Feldman EC, eds. Textbook of veterinary internal medicine: diseases of the dog and the cat. 7th ed. St. Louis, Mo: Elsevier Saunders; 2010:608–615.

^b CRI = constant-rate infusion