Diabetes Mellitus in dogs and cats in 2012: What’s
new? What’s the same?
Linda E. Luther, DVM, DACVIM (SAIM)
Small Animal Track
2012 ISVMA Annual Conference Proceedings
WHAT’S NEW?

Canine insulin options: 2012
o NPH (Humulin® N, Relion® N). Often short duration. Starting dose 0.25-0.5
units/kg.
o rhPZI (ProZinc™). Longer duration, but might result in Somogyi overswing if
it lasts > 12 hours, so some dogs might need once daily administration (but
start w/BID). Starting dose 0.5 units/kg.
o 70% NPH/30% Regular (Humulin® 70/30). Starting dose 0.25-0.5 units/kg.
o Insulin detemir (Levemir®): Starting dose 0.1-0.2 units/kg.

Feline insulin options: 2012
o INSULIN GLARGINE (Lantus®). A recombinant human insulin analog. Starting
dose 0.25 units/kg SQ BID if blood glucose < 360 mg/dL, 0.5 units/kg SQ if
blood glucose > 360 mg/dL.
o Insulin detemir (Levemir®). Similar to insulin glargine. Starting dose 0.25
units/kg SQ BID if blood glucose < 360 mg/dL, 0.5 Units/kg SQ if blood
glucose > 360 mg/dL.
o rhPZI (ProZinc™). A protamine zinc recombinant human insulin. Starting
dose 0.25-0.5 units/kg.

Diet
o
o
Dogs: Feed a high fiber diet (Hill’s w/d, r/d or any ‘lite’ or ‘senior’ food).
Cats: Feed a low-carbohydrate, high protein diet (Purina DM, Hill’s m/d or
Fancy Feast).
WHAT’S THE SAME?

What is diabetes mellitus? **Client education is key**
o Diabetes mellitus is a disease resulting from defects in insulin secretion,
insulin action or both.
 Results in high blood sugar (glucose) and sugar in the urine.
 Symptoms are drinking a lot, urinating a lot and eating a lot, yet losing
weight.
 Goal of treatment is to decrease the clinical signs and improve
quality of life.
o Diagnosis
 PUPD, polyphagia, weight loss, persistent hyperglycemia, glucosuria
o Complications
 *Hypoglycemia* (when a patient is on insulin therapy)
 Lethargy, weakness, ataxia, seizures, coma
 Critical for all owners and staff to know symptoms and what
action to take: Offer food first. If the animal won’t eat, rub
Disclaimer: Please verify all drug dosages before administering.



corn syrup on the gums. Call/bring into clinic. Do not give
insulin again until advised by the veterinarian.
Cataracts (dogs).
Diabetic neuropathy (cats).
DKA: Diabetic ketoacidosis
 Anorexia, vomiting, lethargy.
 May be first presentation.
 There usually is some other factor/disease present beyond.
‘just’ being an untreated diabetic.
 Therapy is regular insulin (or glargine in cats) and
hospitalization.
Monitoring insulin therapy
 Treatment goals: Eliminate symptoms and avoid hypoglycemia.
 #1 = *CLINICAL STATUS*
o Clinical signs, or lack thereof
 PUPD? Polyphagic. Lack of weight loss or weight gain.
 Lack of signs of hypoglycemia.

Glucose curves (see notes below)

Fructosamine levels
o Glycosolated protein that reflects average blood glucose over the prior 2-3
weeks.
o Overswing animals will have normal or increased fructosamine.
o Fructosamine has limited value as a screening test.

Urinalysis
o Check for ketones. Check for lack of glucosuria.
o Do not use to adjust insulin dose.
o Check for urinary tract infections (culture even if no pyuria).

Interval of monitoring varies
o 3 days, 1 week, 2 weeks, 6 weeks, 10 weeks, q. 4 mo.

Each time an animal is presented for a preinsulin glucose level, blood glucose curve
or fructosamine level, assess and record body weight, dosing/time/type of insulin,
degree of PUPD and overall client assessment of the animal’s status.

Insulin resistance is suspected when insulin dose is > 1.5 units/kg. Differential
diagnoses include:
o Post Somogyi overswing
o Infection
o Neoplasia
o Chronic disease
o Diestrus
o Hyperadrenocorticism
o Obesity
o Antibodies
o (Poor injection technique can mimic insulin resistance)
Glucose curves
 IS THE INSULIN EFFECTIVE?
 TIME OF ONSET/PEAK EFFECT?
 DURATION OF ACTION?
 ID GLUCOSE AT NADIR?
 ID PRE-INSULIN GLUCOSE (W/GLARGINE)?
Start with in-hospital curves
o Blood glucose (BG) q 2 hours (w/glargine, start w/pre-insulin blood glucose)
 Typically do the first curve one week after starting insulin.
 If insulin dose is kept the same, and the animal is judged to be stable:
o Run fructosamine level in one month, and if good or excellent control, and
then check fructosamine 1-3x/year.
 If insulin dose is increased:
o Repeat glucose curve and/or phone client one week later.
o If clinical signs are much improved, do glucose curve or plan fructosamine
level in one month.
o If still PUPD, increase insulin further or do glucose curve. After each insulin
dose increase, balance clinical assessment with periodic glucose curves.
 Encourage home glucose curves for improved accuracy and decreased client
expense.
 If clinical evidence of hypoglycemia is observed, review the feeding schedule and
diet, injection technique, do a glucose curve.
 Home glucose curves
o Introduce concept at insulin demo and first recheck. At next recheck(s),
revisit.
o Uses ear margin vein or …
o AlphaTRAK® glucometer
 Spot glucose checks
o Valuable for pre-insulin glucose levels in cats on glargine.
o These are neither accurate nor recommended to assess glycemic control in
animals on other insulin types. Why?
 Time of glucose nadir can vary day-to-day.
 Animals experiencing Somogyi overswing can have BGs that are high
or low at any given time of day.
 If finances are limited, clinical assessment can be the most important
guide to monitoring. Try to encourage home glucose curves when
possible. Spot glucose checks will give a false impression of the
animal’s status.
 Glargine remission
o Best chance of remission is in a new diabetic or within the first 2 years of
diagnosis.
o Greater chance if fed a low carbohydrate diet.
o If pre-insulin BG < 180 mg/dL or nadir BG < 54 mg/dL or 72-126 mg/dL
 Reduce dose by 0.5-1 units/kg or STOP insulin if dose is 0.5-1
units/kg.
o Wait at least 2 weeks after starting insulin in a new diabetic before
discontinuing.
o Monitor for hyperglycemia/glucosuria/clinical signs after stopping insulin.
Some cats will continue to need a very low dose of insulin (i.e. 1 unit once
daily).
Insulin Demo checklist
1. What is diabetes mellitus?
o
o
o
A disease resulting from defects in insulin secretion, insulin action or both, resulting
in high blood sugar (glucose) and sugar in the urine.
Symptoms are drinking a lot, urinating a lot and eating a lot, yet losing weight.
Goal is to decrease the clinical signs and improve quality of life, yet avoid
hypoglycemia.
2. Insulin handling (see insulin syringe handout)
o
o
3.
Injection technique: SQ over dorsal neck, vary location, gently insert needle…don’t
STAB, optimally draw back
o
o
If in doubt that it went in, DON’T REPEAT, wait until next scheduled injection.
o
If animal doesn’t eat well, client should either skip insulin or give decreased dose
(call clinic to ask).
In most cases, insulin is initially given twice daily to dogs and cats, feed the animal
just before insulin injection.
Diet, weight control and exercise
o
o
o
o
4.
Fridge, roll bottle, don’t shake, draw w/o air bubbles, do not ‘predraw’, new syringe
every time, replace bottle when…
Low fat, high fiber diet is recommended for dogs (i.e. w/d diet, or “Lite’ or ‘Senior’
diet). Low carbohydrate, high protein diet is recommended for cats (i.e. DM diet).
Obesity increases insulin resistance so avoid if possible.
Exercise should be regular and moderate.
Every day should be ‘the same’.
Monitoring
o
o
o
o
*Clinical status*
Glucose curves: In clinic and/or at home.
Fructosamine levels
Interval of monitoring for this animal will be: ______________________
5. Complications
o
*Hypoglycemia* or low blood sugar
o Lethargy, weakness, ataxia, seizures, coma.
o Critical for all owners to know symptoms and what action to take.
o Offer food, and if won’t eat, rub corn syrup on gums.
o Call/bring into clinic, and no more insulin until advised.
Go to www.veterinarypartner.com for client handouts and information
Diabetes mellitus references
Della Maggiore A, Nelson RW, Dennis J, Johnson E, Kass PH. “Efficacy of protamine
zinc recombinant human insulin for controlling hyperglycemia in dogs with diabetes
mellitus.” J Vet Intern Med 2012;26:109-115.
Ford SL, Rand JS, Ghormley TM, Lynch HM. “Evaluation of detemir insulin in diabetic
dogs managed with home blood glucose monitoring.” Proc Am Coll Vet Intern Med
2010.
Gilor C, Ridge TK, Attermeier KJ, Graves TK. “Pharmacodynamics of insulin detemir and
insulint glargine assessed by an isoglycemic clamp method in healthy cats.” J Vet Intern
Med 2010;24:870-874.
Marshall RD, Rand JS. “Comparison of the pharmacokinetics and pharmacodynamics of
glargine, protamine zinc and porcine lente insulin in normal cats.” J Vet Intern Med
2002;16(3):373.
Marshall RD, Rand JS. “Insulin glargine and a high protein-low carbohydrate diet are
associated with a high remission rate in newly diagnosed diabetic cats.” J Vet Intern Med
2004;18(3):401.
Marshall RD, Rand JS, Bunew MN, Menrath VH. “Glargine administered intramuscularly
is effective for treatment of feline diabetic ketoacidosis”. Proc Am Coll Vet Inter Med
2010.
Marshall RD, Rand JS, Morton JM. “Treatment of newly diagnosed diabetic cats with
glargine insulin improves glycaemic control and results in higher probability of remission
than protamine zinc and lente insulins.” J Feline Med Surg 2009;11:683-691.
Nelson RW. Canine diabetes mellitus. In Ettinger SJ, Feldman EC (eds.), Textbook of
Veterinary Internal Medicine, 7th edition. Saunders Elsevier, St. Louis, MO. 2010:17821796.
Nelson RW, Henley K, Cole HC, PZIR Clinical Study Group.”Field safety and efficacy of
protamine zinc recombinant human insulin for treatment of diabetes mellitus in cats.” J
Vet Intern Med 2009;23:787-793.
Rand JS. Feline Diabetes Mellitus. In Current Veterinary Therapy XIV, Bonagura JD,
Twedt DC, eds. Sauders Elsevier, St. Louis, 2009, pp. 199-204.
Reusch C. Feline diabetes mellitus. In Ettinger SJ, Feldman EC (eds.), Textbook of
Veterinary Internal Medicine, 7th edition. Saunders Elsevier, St. Louis, MO. 2010:17961816.
Roomp K, Rand JS. “Evaluation of detemir in diabetic cats managed with a protocol for
intensive blood glucose control”. Proc ACVIM forum, 2009.