What rapid‑acting oral carbohydrate and dosage is recommended for a conscious adult with symptomatic hypoglycemia who can swallow?

Oral Glucose Treatment for Adult Hypoglycemia

For a conscious adult with symptomatic hypoglycemia who can swallow, administer 15-20 grams of oral glucose, preferably as pure glucose tablets, which should be chewed and swallowed. 1

Recommended Treatment Protocol

First-Line Treatment

• Administer 15-20 grams of oral/swallowed glucose immediately as the gold standard treatment for conscious adults able to swallow 2, 1
• Pure glucose tablets are the preferred form because they produce a more rapid and predictable glycemic response compared to other carbohydrate sources 1
• The glucose should be chewed and swallowed, not held in the mouth or placed against the cheek 2

Alternative Options When Glucose Tablets Unavailable

• If glucose tablets are not immediately available, use 15 grams of glucose dissolved in 150 mL of water 2
• Any carbohydrate containing glucose may be used as a second-line option, though the response will be slower and less predictable 1
• Avoid using 40% dextrose gel as first-line treatment in adults who can swallow, as it adheres to the mucosa and shows no improvement over tablets at 20 minutes 2

Critical Timing and Monitoring

• Check blood glucose before treatment if possible, then administer glucose immediately 1
• Expect initial response within 10-20 minutes, with blood glucose rising approximately 40 mg/dL with 10 grams or 60 mg/dL with 20 grams over 30-45 minutes 1
• Recheck blood glucose at 15 minutes; if still below 70 mg/dL, repeat the 15-20 gram dose 1

Route of Administration: Why Oral/Swallowed is Superior

The evidence strongly favors oral/swallowed glucose over alternative routes:

• Buccal glucose administration results in significantly lower plasma glucose concentrations at 20 minutes compared to swallowed glucose 2, 1
• Studies comparing buccal spray (0.84 g) versus chewed dextrose tablets (6 g) and buccal instant glucose (15 g) versus swallowed glucose (15 g) both demonstrated fewer participants achieving increased blood glucose with buccal administration 2
• Sublingual administration showed no advantage over oral/swallowed glucose in adults 2

Critical Pitfalls to Avoid

Absolute Contraindications

• Never administer oral glucose to unconscious patients or those unable to protect their airway—use intravenous dextrose or intramuscular glucagon instead 1
• This is a critical safety issue that can result in aspiration and respiratory compromise

Treatment Modifications to Avoid

• Do not add fat to the carbohydrate treatment, as it retards the acute glycemic response and delays correction 1
• Do not add protein to carbohydrate treatment, as it does not affect the glycemic response or prevent subsequent hypoglycemia in type 1 diabetes, and may increase insulin response in type 2 diabetes 1
• Avoid using orange juice or glucose gel as first-line treatment, as studies show minimal blood glucose increment at 10 minutes with these forms 3

Treatment Thresholds

• Treat when blood glucose is below 70 mg/dL, which is the clinically important threshold requiring action 1
• Level 2 hypoglycemia (below 54 mg/dL) requires immediate action as neuroglycopenic symptoms begin at this threshold 1

Post-Treatment Management

• Once symptoms resolve, provide starchy or protein-rich foods if more than 1 hour until the next meal 1
• Any severe hypoglycemic episode requiring external assistance mandates complete reevaluation of the diabetes management plan 1

Evidence Quality Note

While the recommendation for oral/swallowed glucose is strong, the underlying evidence is of very low certainty, downgraded for risk of bias, imprecision, and indirectness 2. However, the consistency of findings across multiple studies and the physiologic rationale support this as the standard of care in real-world clinical practice.