DIABETES MELLITUS CHEAT SHEET
Diabetes Mellitus is a chronic disease where the body cannot regulate blood glucose leading to
hyperglycemia. Insulin is a peptide hormone, secreted from beta cells of the pancreas, which regulates
blood glucose. It allows glucose to enter the cells by causing them to express GLUT2 glucose receptors.
There are two types of diabetes mellitus:
DM 1 - cannot make insulin. Auto-immune. Younger patients. Weaker genetic predisposition.
DM 2 –insulin insensitivity. Older, obese, and minorities. Strong genetic predisposition.
Current criteria for diagnosis of diabetes:
Hemoglobin A1c > 6.5% OR Fasting Plasma Glucose >126 OR 2-hour Oral Glucose Tolerance Test >200
OR hyperglycemic symptoms and a random glucose >200 || Pre-diabetes criteria = A1c 5.7- 6.4
Hemoglobin A1c (glycated hemoglobin or HbA1c) is a form of hemoglobin measured to identify
average plasma glucose over a longer period of time (i.e. approximately the lifespan of a RBC: 120 days).
When glucose levels are high, glucose attaches to the hemoglobin of red blood cells, forming HbA1c.
DM2 is then monitored regular A1C readings with at home glucometers (esp. if on insulin).
Patients on insulin should check blood sugar prior to meals and snacks, occasionally 2 hours after meals,
at bedtime, prior to exercise, and when they suspect low blood glucose.
*Always ask if patient is regularly checking his / her blood sugar and about the range of values.
Review of Systems / HPI Questions to Ask:
 Polyuria / Nocturia
 Erectile dysfunction
 Peripheral neuropathy
o Decreased sensation
o “tingling” sensations in hands/feet
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Vision changes
Nausea/Vomiting/Diarrhea
Constipation/Bloating
Depression/Anxiety
Hx of UTI, infxns in vagina, nails, mouth
* Also ask about episodes of hypoglycemia (with or without symptoms of syncope, light-headedness), as this
is a serious risk of treatment.
Chronic Cx of DM: Small vessel disease: retinopathy, nephropathy, (glycosylation of endothelium)
Large vessel disease: coronary artery disease, vascular occlusive disease
Osmotic damage: neuropathy
Acute Cx of DM: Diabetic Ketoacidosis (DKA) is classically associated with Type 1 DM but can also be
found in DM2, particularly in the late stages where the pancreas has been damaged and insulin secretion
affected. Hyperosmolar Hyperglycemic State (HHS) is found in Type 2 DM.
Physical exam findings to look for:
 Acanthosis nigricans
o Dark, thick, velvety skin on neck or
axilla. Shows insulin resistance.
 Dehydration
 Decreased tactile sensitivity
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Autonomic neuropathy
o orthostatic hypotension
Ulcers (particularly on feet)
Revised 3/10/14. Email Justin.berk@ttuhsc.edu with any feedback.
Labs to Order
- Microalbumin annually
- A1C every 3 months / every 6 months if at goal
- Creatinine (iStat BMP) annually
- Lipid panel annually
Can also consider: TSH, CMP. Annual eye exam by ophthalmologist is recommended.
Treatment:
Goal A1c: <7% using a combination of lifestyle modification, oral therapy (DM2), and insulin.
LIFESTYLE MODIFICATION
Nutrition: Decrease carbohydrate intake, sugar-sweetened beverage cessation
Exercise: 150 minutes / week of moderate aerobic exercise
Education: Smoking cessation, regular foot care
Rec’d Vaccinations: Pneumococcus (one time), Influenza (annually), Hep B (if unvaccinated)
PHARMACOTHERAPY
DM1: Insulin
DM2: 1st line: Metformin | 2nd line: Add second oral agent | 3rd line: third oral or insulin
If urine microalbumin lab is positive, begin ACE-Inhibitor to protect from further diabetic nephropathy
DRUG
Biguanides
EXAMPLE
Metformin
MECHANISM
hepatic gluconeogenesis
NOTE
C/I: kidney
dysfunction
SE: N/V/D, lactic
acidosis (rare)
Glipizide,
Glyburide,
Glimepiride
Insulin secretion
Sulfonylurea
(blocks K+ efflux -> increased Ca+
SE: hypoglycemia
influx -> insulin granule release)
Thiazolidinediones
Activate PPAR nuclear receptors ->
SE: weight gain,
Pioglitazone
(TZDs)
 insulin sensitivity
hepatotoxicity
*Drugs in red = available in Free Clinic. **C/I = contra-indications. SE = common side effects.
Other DM drugs to know about and their side effects:
GLP-1 analogs (Exenatide)- bloating/pancreatitis
DDP-4 inhibitors (Sitagliptin) – pancreatitis
α-glucosidase inhibitors (Acarbose)– abd. gas
SLGT2 inhibitors (canaglifozin)
Injectable Insulin (indicated for DM1 or uncontrolled DM2) – look out for hypoglycemia
TYPE
EXAMPLE
ONSET OF ACTION DURATION OF ACTION
Rapid
Lispro, aspart, glulisine
5-15 minutes
3-6 hours
Short
Regular (R)*
1-2 hours
6-10 hours
Intermediate
isophane (NPH or N)
1-2 hours
10-20 hours
Long
Glargine (Lantus), levemir
1-2 hours
24 hours
Mixed
70% NPH / 30% regular
* 2 brands of insulin available: Humulin and Novolin
Insulin treatments can be managed in several modalities including sliding scale, pre-prandial, and mixed.
“Carb counting” is a technique that can be taught to help patients with pre-prandial insulin dosing. Both
DM1 and DM2 patients require a basal rate of insulin. DM1 patients also require post-prandial coverage.
Revised 3/10/14. Email Justin.berk@ttuhsc.edu with any feedback.