ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
GLP-1 Receptor Agonist (Oral) Pregnancy: Contraindicated — use insulin in pregnancy. Stop at least 2 months before planned conception.

Semaglutide (Oral)

Brand names: Rybelsus

Adult dose

Dose: Starting: 3mg OD for 30 days; increase to 7mg OD for 30 days; increase to 14mg OD if further HbA1c reduction needed
Route: Oral tablet
Frequency: Once daily — must be taken on an empty stomach, with up to 120mL water, at least 30 minutes before any food/drink/other medication
Max: 14mg OD
Oral GLP-1 RA — requires specific administration conditions (empty stomach, small volume water, 30 min fast after) to ensure adequate absorption. If a dose is missed and >12h until next dose, skip; if <12h, take as soon as remembered. Different pharmacokinetics to injectable semaglutide (Ozempic/Wegovy).

Paediatric dose

Route: Oral
Frequency: Once daily
Max: Not applicable
Not licensed under 18 years. Seek specialist opinion.

Dose adjustments

Renal

No dose adjustment required for any degree of renal impairment (PIONEER studies included eGFR ≥15).

Hepatic

No dose adjustment in mild-moderate hepatic impairment. Severe: limited data.

Clinical pearls

  • PIONEER trials: oral semaglutide 14mg non-inferior to injectable dulaglutide 0.75mg and superior to empagliflozin for HbA1c reduction
  • Administration technique critical for efficacy — inadequate absorption if taken with food, large volumes of water, or other medications. Counsel carefully.
  • Weight loss ~3–4kg at 14mg dose — less than injectable semaglutide (Ozempic/Wegovy) due to lower bioavailability
  • Rybelsus (oral) and Ozempic (injectable weekly) are both semaglutide — do NOT prescribe together

Contraindications

  • Personal/family history of medullary thyroid carcinoma
  • MEN type 2
  • Type 1 DM
  • eGFR <15 (limited data)
  • Hypersensitivity to semaglutide

Side effects

  • Nausea (very common, dose-related, usually transient)
  • Vomiting
  • Diarrhoea
  • Constipation
  • Decreased appetite
  • Pancreatitis (rare)
  • Gallbladder disease

Interactions

  • Oral medications — delayed gastric emptying may reduce absorption; take time-critical drugs (levothyroxine, hormonal contraceptives) well before Rybelsus or follow specific separation guidance
  • Warfarin — monitor INR
  • Sulphonylureas — additive hypoglycaemia

Monitoring

  • HbA1c 3–6 monthly
  • Weight and BMI
  • GI side effects (guide dose titration)
  • Lipase if abdominal symptoms

Reference: BNFc; BNF 90; NICE NG28 (Type 2 DM); PIONEER Trials (NEJM 2019). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways