Orthomolecular medicine (often called
“megavitamin therapy”) seeks to use
increased levels of vitamins and minerals
to help treat a variety of medical disorders.
Orthomolecular medicine uses higher doses
than daily vitamins as part of the therapy for
The pet food industry relies on recommendations by the
National Research Council to prevent diseases caused by
nutrient deficiencies in the “average” pet, yet the NRC has
not determined the optimum amount of nutrients or their
effects in treating medical disorders. It is also important to
realize there is no “average” pet. It is unlikely our current
recommendations are adequate to maintain health in every
Owners should not diagnose and treat their pets without
veterinary supervision. Many medical disorder present similar
symptoms. Also, megavitamin therapy can be toxic if not used
The initial approach to orthomolecular therapies
involves a hypoallergenic diet free of by-products, chemical
preservatives, fillers, and artificial colorings and flavorings to
decrease potential hypersensitivity within the gastrointestinal
Treatment uses vitamin A (10,000 IU for small dogs and
cats, up to 30,000 IU for large dogs) and vitamin E (800
IU for small dogs and cats, up to 2400 IU for large dogs).
The antioxidant mineral selenium (20 mcg for small dogs
and cats, up to 60 mcg for large dogs) is also added to the
regimen. Once asymptomatic, a maintenance protocol using
gradually lower dosages of vitamins A and E, and selenium are
prescribed to reduce the chance for toxicity.
Ascorbic acid is not used due to its cholinergic effect on
the intestinal tract which can worsen diarrhea.
Enzymes are used for a variety of functions in pets. Cellular
processes, digestion, and absorption of dietary nutrients are
dependent upon the proper enzymes. Most commonly owners
often think of enzymes as necessary for digestion of food.
In fact, enzymes produced by the pancreas are essential for
digestion of nutrients in the diet. Once properly digested by
pancreatic enzymes, the dietary nutrients can be absorbed by
The pancreas produces amylase, lipase, and various
proteases. Amylase is used for digesting carbohydrates, lipase
is used for digesting fats, and proteases are used by the body
to digest proteins.
While it is true the pancreas produces enzymes to aid in
food digestion, additional enzymes found in the diet contribute
to digestion and absorption as well and may enhance food
efficiency. Natural raw diets contain a number of chemicals,
including enzymes not found in processed diets. Processing
often alters the nutrients found in a pet’s food, depleting it
of important nutrients and enzymes. Enzymes are broken
down in the presence of temperatures of 120 to 160 degrees F,
and in freezing temperatures. Supplying additional enzymes
through the use of supplementation can replenish enzymes
absent in processed foods. Even pets on natural raw diets can
often benefit from additional enzymes, which is why they are
often recommended as a supplement.
In addition, various stressors such as illness, stress,
allergies, food intolerance, age, and various orally administered
medications can decrease gastrointestinal function. This
results in poor digestion and absorption of the nutrients in
How Do Enzymes Work?
There is nothing magical about the enzymes themselves. They
only work by liberating essential nutrients from the pet’s diet.
While we don’t know all the things that enzymes do, it is known
certain enzyme supplements can increase the absorption
of essential vitamins, minerals, and certain fatty acids from
the diet. Increased absorption of zinc, selenium, vitamin B6
and linoleic acid have been detected following plant enzyme
Doctors can prescribe pancreatic enzymes, microbial
enzymes, or plant enzymes. Pancreatic enzymes are adequate
for pets with pancreatic disease where enzyme production and
function is inadequate.
Enzymes have been recommended for various disorders,
including inflammatory bowel disease. The plant enzymes are
active over a much wider pH range than pancreatic enzymes
and are the preferred enzymes for most pets. Plants contain
the enzyme cellulase. Dogs and cats do not normally have
cellulase in their bodies and that’s why they can only digest
some of the plant material in their diets.
Supplementations that contain cellulase in addition to the normal lipase, amylase, and proteases seem to be more
advantageous as these products liberate chemicals such as
zinc, selenium, and linoleic acid that might be bound by fiber.
In one study, supplementing the diet with additional zinc
did not confer the same benefits as supplementation with
plant enzymes. Apparently, the plant enzymes liberate other
nutrients in the diet in addition to zinc resulting in positive
benefits that did not occur simply by increasing the nutrient
Since response is variable regarding the product used, if
one does not help, another supplement might. Since enzymes
are inactivated by heat, they cannot be added to warm food or
mixed with warm water. Rather, they are simply sprinkled on
the room temperature food at the time of feeding.
Enzyme supplementation is inexpensive, safe, and easy
to administer in pill or powder form. Your doctor can help
you decide which product and dosage is best for your pet’s