Changes

====Therapeutic Uses====

====Therapeutic Uses====

High dose niacin supplementation has been shown to reduce low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) while increasing high-density lipoprotein (HDL) cholesterol concentrations in people.<ref>Xenoulis PG and Steiner JM. (2010) '''Lipid metabolism and hyperlipidemia in dogs. '''''Vet J ''2010;183:12-21.</ref> Niacin supplementation has been suggested as a treatment to reduce hypercholesterolemia in dogs,<ref>Goldberg AC.(1998)''' Clinical trial experience with extended-release niacin (Niaspan): dose-escalation study. '''''Am J Cardiol ''1998;82:35U-38U</ref> and has been shown to decrease VLDL synthesis in obese dogs.<ref>Le Bloc’h J, et al.(2010)''' Nicotinic acid decreases apolipoprotein B100-containing lipoprotein levels by reducing hepatic very low density lipoprotein secretion through a possible diacylglycerol acyltransferase 2 inhibition in obese dogs. '''''J Pharmacol Exp Ther ''2010;334:583-589.</ref>

High dose niacin supplementation has been shown to reduce low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) while increasing high-density lipoprotein (HDL) cholesterol concentrations in people.<ref name ="Xenoulis">Xenoulis PG and Steiner JM. (2010) '''Lipid metabolism and hyperlipidemia in dogs. '''''Vet J ''2010;183:12-21.</ref> Niacin supplementation has been suggested as a treatment to reduce hypercholesterolemia in dogs,<ref>Goldberg AC.(1998)''' Clinical trial experience with extended-release niacin (Niaspan): dose-escalation study. '''''Am J Cardiol ''1998;82:35U-38U</ref> and has been shown to decrease VLDL synthesis in obese dogs.<ref>Le Bloc’h J, et al.(2010)''' Nicotinic acid decreases apolipoprotein B100-containing lipoprotein levels by reducing hepatic very low density lipoprotein secretion through a possible diacylglycerol acyltransferase 2 inhibition in obese dogs. '''''J Pharmacol Exp Ther ''2010;334:583-589.</ref>

==Consequences of Niacin Deficiency==

==Consequences of Niacin Deficiency==

====Dogs:====

====Dogs:====

Chronic niacin deficiency in puppy and adult dogs (also called “black-tongue”) causes anorexia, weight loss, erythema of the oral mucosa with progression to inflammation and ulceration, ptyalism, bloody diarrhoea, and eventually death.2

Chronic niacin deficiency in puppy and adult dogs (also called “black-tongue”) causes anorexia, weight loss, erythema of the oral mucosa with progression to inflammation and ulceration, ptyalism, bloody diarrhoea, and eventually death.<ref name="NRC" />

====Cats:====

====Cats:====

Cats and kittens fed niacin deficient diets develop anorexia, fever, erythema of oral mucosa and tongue with eventual ulceration, weight loss, and death within the 2-3 weeks.8,9

Cats and kittens fed niacin deficient diets develop anorexia, fever, erythema of oral mucosa and tongue with eventual ulceration, weight loss, and death within the 2-3 weeks.<ref>Heath MK, ''et al.'' (1940)''' Feline pellagra.''''' Science ''1940;92:514;</ref><ref>Da Silva AC, ''et al.'' (1952)''' The domestic cat as laboratory animal for experimental nutrition studies. II Niacin requirement and tryptophan metabolism.''''' J Nutr'' 1952;1:26-32.</ref>

 

Niacin is prone to degradation with heat processing. Conditions associated with diuresis (e.g., chronic disease, such as renal disease or [[Diabetes Insipidus|diabetes]], or therapeutic intervention, such as intravenous fluids or increased water intake with management of [[Cystitis|lower urinary diseases]]) can result in increased loss of niacin and may increase daily requirements. Patient on chronic haemodialysis are at an increased risk for developing a deficiency.  

Niacin is prone to degradation with heat processing. Conditions associated with diuresis (e.g., chronic disease, such as renal disease or [[Diabetes Insipidus|diabetes]], or therapeutic intervention, such as intravenous fluids or increased water intake with management of [[Cystitis|lower urinary diseases]]) can result in increased loss of niacin and may increase daily requirements. Patient on chronic haemodialysis are at an increased risk for developing a deficiency.  

==Toxicity==

==Toxicity==

There are no published studies evaluating niacin toxicity in cats. In dogs one study reported bloody diarrhoea in 2 dogs that were fed approximately x250 the adult requirement, and chronic exposure (11 days) resulted in death.10 In humans, where it is used to help manage hypercholesterolemia, a high intake niacin (x25 the minimum requirement)  can cause peripheral vasodilation (i.e., “flushing”).5 This side effect of therapeutic niacin has not been evaluated in dogs.

There are no published studies evaluating niacin toxicity in cats. In dogs one study reported bloody diarrhoea in 2 dogs that were fed approximately x250 the adult requirement, and chronic exposure (11 days) resulted in death.<ref>Chen KK, ''et al. ''(1938) '''Toxicity of nicotinic acid. '''''Proc Soc Exp Biol Med ''1938; 38: 241-245. </ref> In humans, where it is used to help manage hypercholesterolemia, a high intake niacin (x25 the minimum requirement)  can cause peripheral vasodilation (i.e., “flushing”).<ref name ="Xenoulis" /> This side effect of therapeutic niacin has not been evaluated in dogs.

==Dietary Sources==

==Dietary Sources==

Niacin is naturally occurring in muscle and organ meats and pulses (i.e., legumes). Dietary niacin is typlically found in the form of nicotinic acid in plant based materials, and as NAD or NADP in animal based materials. Certain whole grains such as corn and sorghum  have a relatively high niacin content, but in these foods niacin is concentrated in the bran and germ layers and has poor [[Nutrition Glossary#Bioavailability|bioavailability]] (i.e., highly bound within the cell), making them  a poor source of dietary niacin. Niacin is also sensitive to degradation with heating and additional supplementation is required with commercial pet foods.  

Niacin is naturally occurring in muscle and organ meats and pulses (i.e., legumes). Dietary niacin is typically found in the form of nicotinic acid in plant based materials, and as NAD or NADP in animal based materials. Certain whole grains such as corn and sorghum  have a relatively high niacin content, but in these foods niacin is concentrated in the bran and germ layers and has poor [[Nutrition Glossary#Bioavailability|bioavailability]] (i.e., highly bound within the cell), making them  a poor source of dietary niacin. Niacin is also sensitive to degradation with heating and additional supplementation is required with commercial pet foods.  

==Diagnosing Niacin Deficiency==

==Diagnosing Niacin Deficiency==

Diagnosis of niacin deficiency can be made using the nicotinamide loading test, which measures urine excretion of niacin metabolites;11 though not routinely tested through veterinary reference laboratories.  

Diagnosis of niacin deficiency can be made using the nicotinamide loading test, which measures urine excretion of niacin metabolites;<ref>Carter EG. (1982) '''Quantitation of urinary niacin metabolites by reversed-phase liquid chromatography. '''''Am J Clin Nutr'' 1982;36:926-30.</ref> though not routinely tested through veterinary reference laboratories.  

Diagnosis is also made on clinical signs consistent with deficiency and evaluation of diet.

Diagnosis is also made on clinical signs consistent with deficiency and evaluation of diet.