NU 578
Unit 4 Study Guide
Key Concepts & Exam Review
University of South Alabama.
This document provides a focused
study guide
It summarizes key concepts, lecture highlights, and
exam-relevant material to support efficient last-
minute review. The guide is structured to help students reinforce
understanding, identify weak areas, and prepare confidently for
the assessment.
, NU 578 Unit 4 Study Guide
Chapter 57: Drugs for Diabetes Mellitus (p. 674-705)
• Short-term complications of DM = hyperglycemia, hypoglycemia, ketoacidosis
• Long-term complications of DM
o Macrovascular disease = increased risk of heart disease, HTN, & stroke, much d/t atherosclerosis
o Microvascular disease = damage to small blood vessels & capillaries
o Retinopathy = DM major cause of blindness in American adults from capillary damage
o Nephropathy = albuminuria, reduced GFR, increased BP = most common cause of ESRD
§ Screen for microalbuminuria; ACE inhibitor or ARB can slow progression (not prevent)
o Sensory & motor neuropathy = nerve degeneration
o Automatic neuropathy (gastroparesis) = n/v, delayed gastric emptying, gastric/intestinal distention = treat with metoclopramide
(dopamine antagonist that promotes gastric emptying)
o Amputations s/t infections = lower limbs d/t glucose-rich environment for bacteria to grow, suppressed immune function, &
diabetic neuropathy = regular foot exams/care important
o Erectile dysfunction = d/t blood vessel injury + neuropathy = treat with sildenafil
• Diabetes in pregnancy = insulin is preferred agent for managing pre-existing T1DM & T2DM; lack of info on metformin; manage
gestational diabetes with diet & medication
• Diagnose DM
o Fasting plasma glucose test = draw at least 8 hrs. after last meal; < 100 = normal; 100-125 = at increased risk aka prediabetes; 126
or > = diabetes
o Oral glucose tolerance test = give PO glucose load & measure plasma glucose 2 hrs later; < 140 = normal, 140-199 = prediabetes,
200 or > = diabetes
o Random plasma glucose test = blood drawn at any time without regard for meals; > 200 WITH s/s (polyuria, polydipsia, rapid wt
loss, possible ketonuria) = diabetes
o Hgb A1C = reflects average BG levels over last 2-3 months; 6.5% or > = diabetes
• Increased risk for diabetes (prediabetes) = reduce risk with diet & exercise & possibly certain PO antidiabetics i.e. metformin
• Overview of treatment
o Goals = prevent complications & manage hyperglycemia
o T1DM = diet, self-monitoring BG, physical activity, insulin replacement = glycemic control while minimizing hypoglycemia =
education
§ Insulin dosage must be coordinated with carbohydrate intake to prevent hypo/hyperglycemia
§ Also manage HTN & dyslipidemia = ACE inhibitor or ARB if albuminuria present; ACEI, ARB, thiazide diuretic, or
CCB if not present; keep BP < 140/90, target 130/80; statins preferred to reduce LDLs, colesevelam another option
o T2DM
§ Step 1 = at diagnosis, initiate lifestyle changes + metformin
§ Step 2 = continue step 1, add 2nd drug, either sulfonylurea, thiazolidinedione, dipeptidyl peptidase-4 (DPP-4)
inhibitor, sodium-glucose cotransporter 2 (SGLT-2) inhibitor, glucagon-like peptide-1 (GLP-1) receptor agonist,
or basal insulin (base choice on relative efficacy, hypoglycemia risk, wt-related considerations, side effect profile, &
cost
§ Step 3 = Progress to 3-drug combo (include metformin)
§ Step 4 = If 3-drug therapy that includes basal insulin fails to reach goals after 3 months, proceed to combination
injectable regimen that includes insulin & possibly a GLP-1 receptor agonist
§ If AIC > 7.5% = start at step 2; if > 10%, may start at step 4
• Monitoring treatment = self-monitoring of blood glucose (recommended for all pts who use insulin plus most T2DM on other therapies);
continuous glucose monitoring (measures interstitial glucose, may adjust insulin delivery); monitor Hgb A1C (Q3-6 months)
• Insulin
o See Table 57.7 p. 684 Types of insulin: time course of action after subcutaneous injection
o See Table 57.8 p. 686 Properties of insulin types
o Short duration: Rapid acting
§ Given in association with meals to control after-meal rise in blood glucose; used in conjunction with intermediate- or
long-acting agents in T1DM
§ All 3 are clear solutions & all require prescription; all given subQ for routine therapy, but may be given IV (rare)
§ Insulin lispro- rapid-acting analog of regular insulin; effects begin within 15-30 minutes of subQ injection; persist for
3-6 hrs = acts faster than regular insulin but has shorter duration of action = can be given immediately before eating;
usually route = subQ or insulin pump
§ Insulin aspart- analog of human insulin with rapid-onset (10-20 min) & short duration (3-5 hrs); dosing with subQ
injection or insulin pump; give 5-15 minutes before meals
§ Insulin glulisine- analog of human insulin with rapid onset (10-15 min) & short duration (3-5 hrs) = administer close to
time of eating; usually given subQ or continuous infusion
§ Inhaled human insulin- faster onset & shorter duration than regular insulin given subQ; used at mealtimes in T1 & T2
DM; available in 4, 8, or 12-unit cartridges = limits dosing to these increments
o Short duration: slower acting
§ Regular insulin- unmodified human insulin; given subQ injection, subQ infusion (analogs used more), IM (rare), & IV
therapy (U-100 only); can be injected before meals to control postprandial hyperglycemia or infused subQ for basal
glycemic control; absorption slightly delayed; effects begin in 30-60 min, peak in 1-5 hrs, & lasts up to 10 hrs; onset
, slower than rapid-acting insulins & faster than long-acting insulins = most insulin pumps use rapid-acting insulins
instead of regular; clear solution; most forms available without prescritpion
• Regular insulin is only kind available in U-500 strength = used for pts with extreme insulin resistance who
take > 200 units/day = NEVER given IV; extra caution & education is critical = must use current syringes
when drawing from vial to avoid OD; requires prescription
o Intermediate duration
§ Neutral Protamine Hagedorn (NPH) insulin- decreased solubility = delayed absorption = delayed onset & extended
duration of action = cannot be given at mealtime to control postprandial hyperglycemia = give BID or TID for glycemic
control between meals & during the night; the only longer-acting insulin suitable for mixing with short-acting insulins;
allergic rxns possible d/t protamine; cloudy suspension = must be agitated before admin; given subQ injection only;
available without prescription
o Long duration
§ Insulin glargine (U-100)- modified human insulin; prolonged duration of action (up to 24 hrs); indicated for once-daily
subq dosing for adults & kids with T1DM & adults with T2DM (some pts may require BID dosing for full 24-hr basal
coverage); may dose anytime during the day, but should be done at same time every day; achieves relatively steady blood
levels; clear solution; do not mix with other insulins; NEVER give IV
§ Insulin detemir- human insulin analog with slow onset; low doses last ~ 12 hrs; higher doses persist ~ 20-24 hrs = use
for basal glycemic control (not given before meals); slower onset & longer duration than NPH insulin; clear solution;
dose once or twice a day via subQ injection; do not give IV; do not mix with other insulins; available by prescription
only
o Longer duration (> 24 hrs)
§ Insulin glargine (U-300)- similar to U-100 form, but 3x as concentrated = prolongs duration of action to be > 24 hrs;
indicated for once-daily subQ dosing in T1 & T2 DM; clear solution
§ Insulin Degludec- used in T1 & T2 DM for basal insulin coverage; dissociates slowly; given subQ; once-daily; available
in U-100 & U-200 (useful for larger doses) concentrations in pre-filled insulin pens only
o All insulins are clear solutions, except for NPH (cloudy) = pts should inspect before admin & discard if it looks abnormal
o Okay to admin IV = regular, aspart, lispro, glulisine
o Okay to mix with other insulins (usually NPH) = regular, aspart, lispro, glulisine
§ Adding protamine (large protein) = decreases solubility = delays absorption = delays onset of action & extends duration
of action
§ Regular insulin + protamine = NPH
§ Lispro + protamine = lispro protamine
§ Aspart + protamine = aspart protamine
§ See Table 57.9 p. 688 Premixed insulin combinations
o If using short-acting insulin in combo with longer-acting insulin = usually desirable to mix in single syringe; NPH is only
longer-acting insulin appropriate for mixing with short-acting insulins = draw short-acting insulin into syringe 1st to avoid
contaminating vial with NPH; mixtures are stable for 28 days
o Concentrations
§ U-100 = 100 units/ml = used for routine replacement therapy = most insulins available in this form
§ U-200 = 200 units/ml = lispro & degludec
§ U-300 = 300 units/ml = glargine
§ U-500 = 500 units/ml Humulin R brand of regular insulin
o Administration
§ All types (except inhaled regular insulin) can be injected subQ
§ Preparation for injection
• NPH = cloudy = must evenly disperse particles before drawing into syringe = roll vial gently between palms
(vigorous agitation = frothing = inaccurate dosing)
• Swab rubber cap with alcohol before loading syringe
• Eliminate air bubbles from syringe after loading
• Clean skin with alcohol (or soap & water) before admin
§ Injection sites
• Most common = upper arm, thigh, abdomen (see Fig 57.3 p. 688)
• Absorption fastest & most consistent in abd; slowest in thigh
• D/t varied rates of absorption = make all injections in same general area (abd vs. thigh), but make injections in
different spots to reduce risk of lipohypertrophy (preferably 1 inch apart); ideally, each spot used only once a
month
§ Injection devices
• Syringe & needle
• Pen injectors- more convenient than syringe & needle; stick needle under skin & inject insulin manually
• Jet injectors- devices that shoot insulin directly through skin into subQ tissue via high pressure (no needle
used), good for needle-phobia, but expensive & difficult to use, can cause stinging, burning, & pain, & bruising
in pts with reduced subQ fat
§ SubQ infusion
• Portable insulin pumps- delivers basal infusion of insulin (usually rapid-acting analogs) plus bolus doses
before each meal (same insulin for basal & mealtime coverage); catheter usually located in abdomen; insulin
levels drop quickly if pump is removed = pump should remain in place most of the day (can be removed for an
hour or 2 for special occasions
, • Implantable insulin pumps- surgically implanted in abd to deliver insulin IV or intraperitoneally; delivers basal
insulin + bolus doses for meals; delivery adjusted by external telemetry; produces superior glycemic control
than daily injections = less hypoglycemia & wt gain & improved quality of life; these are EXPERIMENTAL
§ IV infusion- reserved for emergencies that require rapid reduction in blood glucose & for pts being managed during inpt
setting in hospital = regular, aspart, lispro, & glulisine may be used; regular insulin commonly used d/t less expensive
§ Inhalation- inhaled human insulin (Afrezza) = for mealtime coverage; provides good glycemic control with low
incidence of hypoglycemia & little/no effect on pulmonary function; inhaled at each meal; approved for T1 & T2 DM;
limited to 4, 8, 12-unit cartridges
o Storage = store unopened vials of insulin under refrigeration (can be used until expiration date on vial); do NOT freeze; vial in
current use can be kept at room temp for 1 month (room temp insulin causes less pain & lipodystrophy than cold insulin); avoid
direct sunlight & extreme heat
§ Mixtures of insulins in vials are stable for 1 month at room temp & 3 months in fridge
§ Pre-filled syringes = store in fridge, stable for 1-2 weeks; store vertically with needle pointing up; gently agitate syringe
before admin
o Therapeutic use
§ Principle indication for insulin = DM; required for all T1DM pts & many with T2DM (T2 are more numerous than T1)
• IV insulin used for diabetic ketoacidosis
• Insulin promotes cellular uptake of K = lowers plasma K levels = infusion also used to acutely treat
hyperkalemia
• Can also aid in diagnosis of growth hormone deficiency
§ Insulin preferred drug for managing gestational diabetes
§ Insulin dosage must match insulin need = increase in carb intake = increase in insulin dosage; if skipping meal, low
carb intake, or increased physical activity = decrease insulin dosage; insulin needs also increased by infection, stress,
obesity, adolescent growth spurt, & pregnancy (after 1st trimester); insulin needs decreased by exercise & 1st trim of
pregnancy
§ Pts must receive thorough education on
• The nature of diabetes
• The importance of optimal glucose control
• Major components of tx routine (insulin replacement, SMBG, diet, exercise)
• Procedures for purchasing insulin, syringes, & needles
• Importance of avoiding arbitrary changes b/t insulin from different manufacturers
• Methods of insulin storage
• Procedures for mixing insulins (if applicable)
• Calculations of dosage adjustments
• Techniques of insulin administration
• Methods for monitoring blood glucose
§ Complications of insulin treatment
• Hypoglycemia (BG < 70) = when insulin levels exceed insulin needs (major cause = OD; also from reduced
intake of foods, vomiting/diarrhea, excessive alcohol consumption, intense exercise, & childbirth)
o Pt & family should know s/s of hypoglycemia (rapid fall = tachycardia, palpitations, sweating,
nervousness; gradual fall = HA, confusion, drowsiness, fatigue; if severe = convulsions, coma, death)
o Rapid tx mandatory to prevent irreversible brain damage & death; if conscious = give fast-acting PO
sugar (glucose tabs, OJ, sugar cubes, honey, corn syrup, non-diet soda); if swallowing/gag reflex
suppressed = NPO; severe = IV glucose preferred (parenteral glucagon alternative)
o Diabetics should always have a PO carb available (candy, sugar cube, glucose tab); glucagon
recommended to be kept on hand as well (esp if on insulin or at high risk for hypoglycemia)
o Hypoglycemia unawareness = don’t feel symptoms until BG dangerously low = frequently monitor
BG
• Hypokalemia = insulin promotes uptake of K by cells = lowers blood levels of K in excessive doses = can
reduce contractility of heart = produce fatal dysrhythmias
• Lipohypertrophy = accumulation of subQ fat; occurs when insulin is injected too frequently at same site =
minimize by rotating sites
• Allergic rxns = rare; widespread red itchy welts, may have difficulty breathing; may need desensitization
§ Drug interactions
• Hypoglycemic agents = sulfonylureas, glinides, alcohol; may intensify hypoglycemia = use special care
• Hyperglycemic agents = glucocorticoids, sympathomimetics; counteract desired effects of insulin = may
need increased dose
• Beta blockers = can mask signs of hypoglycemia (tachycardia, palpitations) = delay awareness & response;
also impairs glycogenolysis = prevents counterregulatory response = worsens insulin-induced hypoglycemia
(esp noncardiac selective BBs i.e. propranolol)
• Non-insulin medications for treatment of diabetes
o See Table 57.10 p. 693 Drugs for T2DM
o PO drugs
§ Biguanides: Metformin
• Drug of choice for initial therapy in most pts with T2DM (typically started immediately after dx); lowers BG &
improves glucose tolerance by inhibiting glucose production in liver, sensitizing insulin receptors in target
tissues (fat & skeletal muscle) = increases glucose uptake in response to insulin available, & slightly reduces
Unit 4 Study Guide
Key Concepts & Exam Review
University of South Alabama.
This document provides a focused
study guide
It summarizes key concepts, lecture highlights, and
exam-relevant material to support efficient last-
minute review. The guide is structured to help students reinforce
understanding, identify weak areas, and prepare confidently for
the assessment.
, NU 578 Unit 4 Study Guide
Chapter 57: Drugs for Diabetes Mellitus (p. 674-705)
• Short-term complications of DM = hyperglycemia, hypoglycemia, ketoacidosis
• Long-term complications of DM
o Macrovascular disease = increased risk of heart disease, HTN, & stroke, much d/t atherosclerosis
o Microvascular disease = damage to small blood vessels & capillaries
o Retinopathy = DM major cause of blindness in American adults from capillary damage
o Nephropathy = albuminuria, reduced GFR, increased BP = most common cause of ESRD
§ Screen for microalbuminuria; ACE inhibitor or ARB can slow progression (not prevent)
o Sensory & motor neuropathy = nerve degeneration
o Automatic neuropathy (gastroparesis) = n/v, delayed gastric emptying, gastric/intestinal distention = treat with metoclopramide
(dopamine antagonist that promotes gastric emptying)
o Amputations s/t infections = lower limbs d/t glucose-rich environment for bacteria to grow, suppressed immune function, &
diabetic neuropathy = regular foot exams/care important
o Erectile dysfunction = d/t blood vessel injury + neuropathy = treat with sildenafil
• Diabetes in pregnancy = insulin is preferred agent for managing pre-existing T1DM & T2DM; lack of info on metformin; manage
gestational diabetes with diet & medication
• Diagnose DM
o Fasting plasma glucose test = draw at least 8 hrs. after last meal; < 100 = normal; 100-125 = at increased risk aka prediabetes; 126
or > = diabetes
o Oral glucose tolerance test = give PO glucose load & measure plasma glucose 2 hrs later; < 140 = normal, 140-199 = prediabetes,
200 or > = diabetes
o Random plasma glucose test = blood drawn at any time without regard for meals; > 200 WITH s/s (polyuria, polydipsia, rapid wt
loss, possible ketonuria) = diabetes
o Hgb A1C = reflects average BG levels over last 2-3 months; 6.5% or > = diabetes
• Increased risk for diabetes (prediabetes) = reduce risk with diet & exercise & possibly certain PO antidiabetics i.e. metformin
• Overview of treatment
o Goals = prevent complications & manage hyperglycemia
o T1DM = diet, self-monitoring BG, physical activity, insulin replacement = glycemic control while minimizing hypoglycemia =
education
§ Insulin dosage must be coordinated with carbohydrate intake to prevent hypo/hyperglycemia
§ Also manage HTN & dyslipidemia = ACE inhibitor or ARB if albuminuria present; ACEI, ARB, thiazide diuretic, or
CCB if not present; keep BP < 140/90, target 130/80; statins preferred to reduce LDLs, colesevelam another option
o T2DM
§ Step 1 = at diagnosis, initiate lifestyle changes + metformin
§ Step 2 = continue step 1, add 2nd drug, either sulfonylurea, thiazolidinedione, dipeptidyl peptidase-4 (DPP-4)
inhibitor, sodium-glucose cotransporter 2 (SGLT-2) inhibitor, glucagon-like peptide-1 (GLP-1) receptor agonist,
or basal insulin (base choice on relative efficacy, hypoglycemia risk, wt-related considerations, side effect profile, &
cost
§ Step 3 = Progress to 3-drug combo (include metformin)
§ Step 4 = If 3-drug therapy that includes basal insulin fails to reach goals after 3 months, proceed to combination
injectable regimen that includes insulin & possibly a GLP-1 receptor agonist
§ If AIC > 7.5% = start at step 2; if > 10%, may start at step 4
• Monitoring treatment = self-monitoring of blood glucose (recommended for all pts who use insulin plus most T2DM on other therapies);
continuous glucose monitoring (measures interstitial glucose, may adjust insulin delivery); monitor Hgb A1C (Q3-6 months)
• Insulin
o See Table 57.7 p. 684 Types of insulin: time course of action after subcutaneous injection
o See Table 57.8 p. 686 Properties of insulin types
o Short duration: Rapid acting
§ Given in association with meals to control after-meal rise in blood glucose; used in conjunction with intermediate- or
long-acting agents in T1DM
§ All 3 are clear solutions & all require prescription; all given subQ for routine therapy, but may be given IV (rare)
§ Insulin lispro- rapid-acting analog of regular insulin; effects begin within 15-30 minutes of subQ injection; persist for
3-6 hrs = acts faster than regular insulin but has shorter duration of action = can be given immediately before eating;
usually route = subQ or insulin pump
§ Insulin aspart- analog of human insulin with rapid-onset (10-20 min) & short duration (3-5 hrs); dosing with subQ
injection or insulin pump; give 5-15 minutes before meals
§ Insulin glulisine- analog of human insulin with rapid onset (10-15 min) & short duration (3-5 hrs) = administer close to
time of eating; usually given subQ or continuous infusion
§ Inhaled human insulin- faster onset & shorter duration than regular insulin given subQ; used at mealtimes in T1 & T2
DM; available in 4, 8, or 12-unit cartridges = limits dosing to these increments
o Short duration: slower acting
§ Regular insulin- unmodified human insulin; given subQ injection, subQ infusion (analogs used more), IM (rare), & IV
therapy (U-100 only); can be injected before meals to control postprandial hyperglycemia or infused subQ for basal
glycemic control; absorption slightly delayed; effects begin in 30-60 min, peak in 1-5 hrs, & lasts up to 10 hrs; onset
, slower than rapid-acting insulins & faster than long-acting insulins = most insulin pumps use rapid-acting insulins
instead of regular; clear solution; most forms available without prescritpion
• Regular insulin is only kind available in U-500 strength = used for pts with extreme insulin resistance who
take > 200 units/day = NEVER given IV; extra caution & education is critical = must use current syringes
when drawing from vial to avoid OD; requires prescription
o Intermediate duration
§ Neutral Protamine Hagedorn (NPH) insulin- decreased solubility = delayed absorption = delayed onset & extended
duration of action = cannot be given at mealtime to control postprandial hyperglycemia = give BID or TID for glycemic
control between meals & during the night; the only longer-acting insulin suitable for mixing with short-acting insulins;
allergic rxns possible d/t protamine; cloudy suspension = must be agitated before admin; given subQ injection only;
available without prescription
o Long duration
§ Insulin glargine (U-100)- modified human insulin; prolonged duration of action (up to 24 hrs); indicated for once-daily
subq dosing for adults & kids with T1DM & adults with T2DM (some pts may require BID dosing for full 24-hr basal
coverage); may dose anytime during the day, but should be done at same time every day; achieves relatively steady blood
levels; clear solution; do not mix with other insulins; NEVER give IV
§ Insulin detemir- human insulin analog with slow onset; low doses last ~ 12 hrs; higher doses persist ~ 20-24 hrs = use
for basal glycemic control (not given before meals); slower onset & longer duration than NPH insulin; clear solution;
dose once or twice a day via subQ injection; do not give IV; do not mix with other insulins; available by prescription
only
o Longer duration (> 24 hrs)
§ Insulin glargine (U-300)- similar to U-100 form, but 3x as concentrated = prolongs duration of action to be > 24 hrs;
indicated for once-daily subQ dosing in T1 & T2 DM; clear solution
§ Insulin Degludec- used in T1 & T2 DM for basal insulin coverage; dissociates slowly; given subQ; once-daily; available
in U-100 & U-200 (useful for larger doses) concentrations in pre-filled insulin pens only
o All insulins are clear solutions, except for NPH (cloudy) = pts should inspect before admin & discard if it looks abnormal
o Okay to admin IV = regular, aspart, lispro, glulisine
o Okay to mix with other insulins (usually NPH) = regular, aspart, lispro, glulisine
§ Adding protamine (large protein) = decreases solubility = delays absorption = delays onset of action & extends duration
of action
§ Regular insulin + protamine = NPH
§ Lispro + protamine = lispro protamine
§ Aspart + protamine = aspart protamine
§ See Table 57.9 p. 688 Premixed insulin combinations
o If using short-acting insulin in combo with longer-acting insulin = usually desirable to mix in single syringe; NPH is only
longer-acting insulin appropriate for mixing with short-acting insulins = draw short-acting insulin into syringe 1st to avoid
contaminating vial with NPH; mixtures are stable for 28 days
o Concentrations
§ U-100 = 100 units/ml = used for routine replacement therapy = most insulins available in this form
§ U-200 = 200 units/ml = lispro & degludec
§ U-300 = 300 units/ml = glargine
§ U-500 = 500 units/ml Humulin R brand of regular insulin
o Administration
§ All types (except inhaled regular insulin) can be injected subQ
§ Preparation for injection
• NPH = cloudy = must evenly disperse particles before drawing into syringe = roll vial gently between palms
(vigorous agitation = frothing = inaccurate dosing)
• Swab rubber cap with alcohol before loading syringe
• Eliminate air bubbles from syringe after loading
• Clean skin with alcohol (or soap & water) before admin
§ Injection sites
• Most common = upper arm, thigh, abdomen (see Fig 57.3 p. 688)
• Absorption fastest & most consistent in abd; slowest in thigh
• D/t varied rates of absorption = make all injections in same general area (abd vs. thigh), but make injections in
different spots to reduce risk of lipohypertrophy (preferably 1 inch apart); ideally, each spot used only once a
month
§ Injection devices
• Syringe & needle
• Pen injectors- more convenient than syringe & needle; stick needle under skin & inject insulin manually
• Jet injectors- devices that shoot insulin directly through skin into subQ tissue via high pressure (no needle
used), good for needle-phobia, but expensive & difficult to use, can cause stinging, burning, & pain, & bruising
in pts with reduced subQ fat
§ SubQ infusion
• Portable insulin pumps- delivers basal infusion of insulin (usually rapid-acting analogs) plus bolus doses
before each meal (same insulin for basal & mealtime coverage); catheter usually located in abdomen; insulin
levels drop quickly if pump is removed = pump should remain in place most of the day (can be removed for an
hour or 2 for special occasions
, • Implantable insulin pumps- surgically implanted in abd to deliver insulin IV or intraperitoneally; delivers basal
insulin + bolus doses for meals; delivery adjusted by external telemetry; produces superior glycemic control
than daily injections = less hypoglycemia & wt gain & improved quality of life; these are EXPERIMENTAL
§ IV infusion- reserved for emergencies that require rapid reduction in blood glucose & for pts being managed during inpt
setting in hospital = regular, aspart, lispro, & glulisine may be used; regular insulin commonly used d/t less expensive
§ Inhalation- inhaled human insulin (Afrezza) = for mealtime coverage; provides good glycemic control with low
incidence of hypoglycemia & little/no effect on pulmonary function; inhaled at each meal; approved for T1 & T2 DM;
limited to 4, 8, 12-unit cartridges
o Storage = store unopened vials of insulin under refrigeration (can be used until expiration date on vial); do NOT freeze; vial in
current use can be kept at room temp for 1 month (room temp insulin causes less pain & lipodystrophy than cold insulin); avoid
direct sunlight & extreme heat
§ Mixtures of insulins in vials are stable for 1 month at room temp & 3 months in fridge
§ Pre-filled syringes = store in fridge, stable for 1-2 weeks; store vertically with needle pointing up; gently agitate syringe
before admin
o Therapeutic use
§ Principle indication for insulin = DM; required for all T1DM pts & many with T2DM (T2 are more numerous than T1)
• IV insulin used for diabetic ketoacidosis
• Insulin promotes cellular uptake of K = lowers plasma K levels = infusion also used to acutely treat
hyperkalemia
• Can also aid in diagnosis of growth hormone deficiency
§ Insulin preferred drug for managing gestational diabetes
§ Insulin dosage must match insulin need = increase in carb intake = increase in insulin dosage; if skipping meal, low
carb intake, or increased physical activity = decrease insulin dosage; insulin needs also increased by infection, stress,
obesity, adolescent growth spurt, & pregnancy (after 1st trimester); insulin needs decreased by exercise & 1st trim of
pregnancy
§ Pts must receive thorough education on
• The nature of diabetes
• The importance of optimal glucose control
• Major components of tx routine (insulin replacement, SMBG, diet, exercise)
• Procedures for purchasing insulin, syringes, & needles
• Importance of avoiding arbitrary changes b/t insulin from different manufacturers
• Methods of insulin storage
• Procedures for mixing insulins (if applicable)
• Calculations of dosage adjustments
• Techniques of insulin administration
• Methods for monitoring blood glucose
§ Complications of insulin treatment
• Hypoglycemia (BG < 70) = when insulin levels exceed insulin needs (major cause = OD; also from reduced
intake of foods, vomiting/diarrhea, excessive alcohol consumption, intense exercise, & childbirth)
o Pt & family should know s/s of hypoglycemia (rapid fall = tachycardia, palpitations, sweating,
nervousness; gradual fall = HA, confusion, drowsiness, fatigue; if severe = convulsions, coma, death)
o Rapid tx mandatory to prevent irreversible brain damage & death; if conscious = give fast-acting PO
sugar (glucose tabs, OJ, sugar cubes, honey, corn syrup, non-diet soda); if swallowing/gag reflex
suppressed = NPO; severe = IV glucose preferred (parenteral glucagon alternative)
o Diabetics should always have a PO carb available (candy, sugar cube, glucose tab); glucagon
recommended to be kept on hand as well (esp if on insulin or at high risk for hypoglycemia)
o Hypoglycemia unawareness = don’t feel symptoms until BG dangerously low = frequently monitor
BG
• Hypokalemia = insulin promotes uptake of K by cells = lowers blood levels of K in excessive doses = can
reduce contractility of heart = produce fatal dysrhythmias
• Lipohypertrophy = accumulation of subQ fat; occurs when insulin is injected too frequently at same site =
minimize by rotating sites
• Allergic rxns = rare; widespread red itchy welts, may have difficulty breathing; may need desensitization
§ Drug interactions
• Hypoglycemic agents = sulfonylureas, glinides, alcohol; may intensify hypoglycemia = use special care
• Hyperglycemic agents = glucocorticoids, sympathomimetics; counteract desired effects of insulin = may
need increased dose
• Beta blockers = can mask signs of hypoglycemia (tachycardia, palpitations) = delay awareness & response;
also impairs glycogenolysis = prevents counterregulatory response = worsens insulin-induced hypoglycemia
(esp noncardiac selective BBs i.e. propranolol)
• Non-insulin medications for treatment of diabetes
o See Table 57.10 p. 693 Drugs for T2DM
o PO drugs
§ Biguanides: Metformin
• Drug of choice for initial therapy in most pts with T2DM (typically started immediately after dx); lowers BG &
improves glucose tolerance by inhibiting glucose production in liver, sensitizing insulin receptors in target
tissues (fat & skeletal muscle) = increases glucose uptake in response to insulin available, & slightly reduces
