Acarbose

Alpha-Glucosidase Inhibitor·Endocrinology - Oral Antidiabetics

Type 2 Diabetes (specifically for patients with high post-prandial glucose spikes)

Authority requiredPBSORALGlucobay50 mg tablet+2

Max Dose

300 mg/day

Half-life

2 h

Flatulence

SEVERE

Timing

FIRST BITE

Rapid Summary

Overview

Alpha-glucosidase inhibitor. Acts entirely in the gut to delay the digestion of complex carbohydrates. Blunts post-meal glucose spikes but causes horrific flatulence.

Maximum Dose

Take with food

Max 300 mg/day (100 mg TDS with meals).

Clinical Focus

If the patient experiences a 'hypo' while on this drug (due to another med like insulin), you MUST give them pure glucose (jellybeans/dextrose). Table sugar (sucrose) will not work because the drug blocks its digestion.

Bottom Line

Acarbose is an alpha-glucosidase inhibitor that reduces postprandial glucose spikes, but causes significant flatulence and GI intolerance limiting adherence.

Formulation & Access

Brand Names

Glucobay

Oral Routes

Tablets (50 mg, 100 mg).

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Type 2 Diabetes (specifically for patients with high post-prandial glucose spikes).

Clinical Place

Rarely used as first-line therapy anymore due to severe GI intolerance, but highly effective for isolated post-meal spikes.

Quick reference

Class & Role

Alpha-Glucosidase Inhibitor — Alpha-glucosidase inhibitor.

Route / Formulation

Tablets (50 mg, 100 mg). (Glucobay)

Usual Dose & Max

Start PO 50 mg OD to TDS. Titrate very slowly to 100 mg TDS. MUST be taken with the first bite of the main meal. Max 300 mg/day (100 mg TDS with meals).

Key Indication Doses

Type 2 Diabetes: Start PO 50 mg OD to TDS. Titrate very slowly to 100 mg TDS. MUST be taken with the first bite of the main meal. Renal Impairment: Avoid if eGFR < 25.

Best Uses

Acarbose is an alpha-glucosidase inhibitor that reduces postprandial glucose spikes, but causes significant flatulence and GI intolerance limiting adherence.

Avoid / Cautions

Inflammatory Bowel Disease (IBD), partial bowel obstruction, severe hernias (gas distension is dangerous). Pregnancy Category B3.

Key Risks

Gastrointestinal: Severe flatulence (farting), bloating, abdominal pain, diarrhea. Occurs because the undigested carbohydrates pass into the colon, where bacteria ferment them into massive amounts of gas. Hepatic: Rare transaminitis at max doses.

Key Interactions

Antacids and digestive enzymes (e.g., Creon) will alter or abolish its effect.

Monitoring

Ensure the patient takes it EXACTLY with the first mouthful of food. If taken 30 mins before or after the meal, it does absolutely nothing. Routine HbA1c.

Clinical Pearl

Acarbose blocks the enzyme that splits sucrose (table sugar/candy) into glucose. If a patient on Acarbose and Gliclazide goes 'hypo', giving them a chocolate bar or table sugar will fail to raise their blood sugar. They MUST be given pure Dextrose tablets or Glucose gel, which require no digestion.

Access

Authority requiredGlucobay50 mg tablet

Brand: Glucobay
PBS status: Authority required
Formulation: Tablets (50 mg, 100 mg)

Acarbose

Alpha-Glucosidase Inhibitor·Endocrinology - Oral Antidiabetics

Type 2 Diabetes (specifically for patients with high post-prandial glucose spikes)

Authority requiredPBSORALGlucobay50 mg tablet+2

Max Dose

300 mg/day

Half-life

2 h

Flatulence

SEVERE

Timing

FIRST BITE

Rapid Summary

Overview

Alpha-glucosidase inhibitor. Acts entirely in the gut to delay the digestion of complex carbohydrates. Blunts post-meal glucose spikes but causes horrific flatulence.

Maximum Dose

Take with food

Max 300 mg/day (100 mg TDS with meals).

Clinical Focus

Bottom Line

Acarbose is an alpha-glucosidase inhibitor that reduces postprandial glucose spikes, but causes significant flatulence and GI intolerance limiting adherence.

Formulation & Access

Brand Names

Glucobay

Oral Routes

Tablets (50 mg, 100 mg).

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Type 2 Diabetes (specifically for patients with high post-prandial glucose spikes).

Clinical Place

Rarely used as first-line therapy anymore due to severe GI intolerance, but highly effective for isolated post-meal spikes.

Quick reference

Class & Role

Alpha-Glucosidase Inhibitor — Alpha-glucosidase inhibitor.

Route / Formulation

Tablets (50 mg, 100 mg). (Glucobay)

Usual Dose & Max

Start PO 50 mg OD to TDS. Titrate very slowly to 100 mg TDS. MUST be taken with the first bite of the main meal. Max 300 mg/day (100 mg TDS with meals).

Key Indication Doses

Type 2 Diabetes: Start PO 50 mg OD to TDS. Titrate very slowly to 100 mg TDS. MUST be taken with the first bite of the main meal. Renal Impairment: Avoid if eGFR < 25.

Best Uses

Acarbose is an alpha-glucosidase inhibitor that reduces postprandial glucose spikes, but causes significant flatulence and GI intolerance limiting adherence.

Avoid / Cautions

Inflammatory Bowel Disease (IBD), partial bowel obstruction, severe hernias (gas distension is dangerous). Pregnancy Category B3.

Key Risks

Key Interactions

Antacids and digestive enzymes (e.g., Creon) will alter or abolish its effect.

Monitoring

Ensure the patient takes it EXACTLY with the first mouthful of food. If taken 30 mins before or after the meal, it does absolutely nothing. Routine HbA1c.

Clinical Pearl

Access

Authority requiredGlucobay50 mg tablet

Brand: Glucobay
PBS status: Authority required
Formulation: Tablets (50 mg, 100 mg)