What is the recommended IV dosage of metoclopramide for a diabetic patient with a history of DKA and HHS experiencing nausea and vomiting?

IV Metoclopramide Administration for Diabetic Gastroparesis with Nausea/Vomiting

For a diabetic patient with DKA/HHS history experiencing nausea and vomiting, administer metoclopramide 10 mg IV slowly over 1-2 minutes, which can be repeated every 6-8 hours as needed (maximum 40 mg/day). 1

Dosing Protocol

Standard IV Dosing

• Administer 10 mg IV push slowly over 1-2 minutes for symptomatic relief of diabetic gastroparesis 1
• May repeat doses every 6-8 hours based on symptom severity (typical dosing is 5-20 mg three to four times daily) 2
• Do not exceed 10 mg per dose when given IV for gastroparesis symptoms 1

Administration Technique

• Give undiluted as a slow IV push over 1-2 minutes 1
• For chemotherapy-related nausea (not applicable here but illustrates dilution requirements), doses >10 mg require dilution in 50 mL normal saline and infusion over ≥15 minutes 1

Duration of Therapy

• IV administration may be required for up to 10 days before symptoms subside sufficiently to transition to oral therapy 1
• Once acute symptoms improve, transition to oral metoclopramide 10 mg three to four times daily before meals and at bedtime 2

Special Considerations in DKA/HHS Context

Renal Impairment Dosing

• If creatinine clearance <40 mL/min, initiate therapy at approximately half the recommended dose (5 mg instead of 10 mg) 1
• This is critical in DKA/HHS patients who often present with acute kidney injury from volume depletion 3, 4

Timing Relative to DKA Treatment

• Metoclopramide can be administered concurrently with DKA management (fluid resuscitation and insulin therapy) 3, 4
• Monitor blood glucose closely, as IV metoclopramide may increase postprandial hyperglycemia at 120 minutes post-administration 5
• This effect is generally modest and should not preclude use when nausea/vomiting control is needed 5

Electrolyte Monitoring

• Ensure adequate potassium repletion before and during metoclopramide use, as both insulin therapy and improved gastric emptying may affect potassium balance 3, 4

Monitoring and Adverse Effects

Acute Dystonic Reactions

• If acute dystonic reactions occur, immediately administer diphenhydramine 50 mg IM 1
• Dystonic reactions are more common with IV administration and higher doses 1
• CNS side effects (somnolence, akathisia, reduced mental acuity) occur in 29-49% of patients but are generally mild 6

Efficacy Monitoring

• Assess symptom relief (nausea, vomiting, early satiety, bloating) within 24-48 hours 7, 6
• Note that tolerance to gastrokinetic effects may develop with chronic use, though antiemetic properties persist 8, 7

Alternative Considerations

When IV Metoclopramide Fails

• Consider rectal metoclopramide 25 mg suppositories if oral route remains unavailable and IV therapy is inadequate 9
• Alternative antiemetics include ondansetron 4-8 mg IV or prochlorperazine 5-10 mg IV 2

Contraindications to Verify

• Ensure no mechanical bowel obstruction is present before administration 1
• Avoid in patients with known hypersensitivity or those taking medications that may cause extrapyramidal reactions 1

Transition to Oral Therapy

• Once the patient tolerates oral intake and DKA has resolved (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L), transition to oral metoclopramide 10 mg four times daily before meals and at bedtime 2, 3, 4, 1