Drug

Dosage

Formulations

Comments (Metabolism)

Oral Agents

2nd-Generation Sulfonylureas

Increase insulin secretion; lower HbA_1c by 1.0%–2.0%

Glimepiride (Amaryl )

4–8 mg once, begin 1–2 mg

T: 1, 2, 4

Numerous drug interactions, long-acting (L, K)

Glipizide (generic or Glucotrol)

2.5–40 mg once or divided

T: 5, 10

Short-acting (L, K)

(Glucotrol XL)

5–20 mg once

T: ER 2.5, 5, 10

Long-acting (L, K)

Glyburide (generic or Diaβeta, Micronase)

1.25–20 mg once or divided

T: 1.25, 2.5, 5

Long-acting, risk of hypoglycemia (L, K)

Micronized glyburide (Glynase)

1.5–12 mg once

T: 1.5, 3, 4.5, 6

(L, K)

α-Glucosidase Inhibitors

Delay glucose absorption; lower HbA_1c by 0.5%–1.0%

Acarbose (Precose)

50–100 mg tid, just before meals; start with 25 mg

T: 25, 50, 100

GI adverse effects common, avoid if Cr > 2 mg/dL, monitor liver enzymes (gut, K)

Miglitol (Glyset)

25–100 mg tid, with 1st bite of meal; start with 25 mg qd

T: 25, 50, 100

Same as acarbose but no need to monitor liver enzymes (L, K)

Biguanides

Decrease hepatic glucose production; lower HbA_1c by 1.0%–2.0%

Metformin (Glucophage)

500–2550 mg divided

T: 500, 850, 1000

Avoid in patients > 80 yr, Cr > 1.5 in men, Cr > 1.4 in women, HF, COPD, elevated liver enzymes; hold before contrast radiologic studies; may cause weight loss (K)

(Glucophage XR )

1500–2000 mg qd

T: ER 500

Same as above

Meglitinides

Increase insulin secretion; lower HbA_1c by 1.0%–2.0%

Nateglinide (Starlix)

60–120 mg tid

T: 60, 120

Give 30 min before meals

Repaglinide (Prandin)

0.5 mg bid–qid if HbA_1c < 8% or previously untreated

1–2 mg bid–qid if HbA_1c ≥ 8% or previously treated

T: 0.5, 1, 2

Give 30 min before meals; adjust dose at wkly intervals; potential for drug interactions, caution in hepatic, renal insufficiency (L)

Thiazolidinediones

Insulin resistance reducers; lower HbA_1c by 0.5%–1.0%; risk of HF; avoid if NYHA Class III or IV cardiac status; D/C if any decline in cardiac status

Pioglitazone (Actos)

15 or 30 mg qd; max 45 mg/d as monotherapy, 30 mg/d in combination therapy

T: 15, 30, 45

Check liver enzymes at start, q 2 mo during 1st yr, then periodically; avoid if clinical evidence of liver disease or if serum ALT levels > 2.5 upper limit of normal (L, K)

Rosiglitazone (Avandia)

4 mg qd–bid

T: 2, 4, 8

Check liver enzymes at start, q 2 mo during 1st yr, then periodically; avoid if clinical evidence of liver disease or if serum ALT levels > 2.5 upper limit of normal (L, K)

Combinations

Glipizide and metformin (METAGLIP)

2.5/250 once; 20/2000 in 2 divided doses

T: 2.5/250, 2.5/500, 5/500

Avoid in patients > 80 yr, Cr > 1.5 in men, Cr > 1.4 in women; see individual drugs (L, K)

Glyburide and metformin (Glucovance)

1.25/250 mg initially if previously untreated; 2.5/500 mg or 5/500 mg bid with meals; max 20/2000/d

T: 1.25/250, 2.5/500, 5/500

Starting dose should not exceed the total daily dose of either drug; see also individual drugs

Rosiglitazone and metformin (Avandamet)

4/1000–8/2000 in 2 divided doses

T: 1/500, 2/500, 4/500, 2/1000, 4/1000

Avoid in patients > 80 yr, Cr > 1.5 in men, Cr > 1.4 in women; see individual drugs (L, K)

Injectable Agents

Exenatide (Byetta)

5–10 µg SC bid

1.2-, 2.4-mL prefilled syringes

Incretin mimetic; lowers HbA1c by 0.4%–0.9%; nausea and hypoglycemia common; less weight gain than insulin; avoid if CrCl < 30 mL/min (K)

Pramlintide (Symlin)*

60 µg SC immediately before meals

0.6 mg/mL in 5-mL vial

Amylin analogue; lowers HbA_1c by 0.4%–0.7%; nausea and hypoglycemia common; reduce pre-meal dose of short-acting insulin by 50% (K)