Ultra-long-acting Insulin Analogue Pregnancy: May be considered during pregnancy if clinically needed; intensified blood-glucose control and monitoring recommended (insulin requirements usually decrease in the first trimester and increase during the second and third).

Insulin Degludec

Brand names: Tresiba

Insulin degludec is an ultra-long-acting basal insulin analogue used once daily to provide background insulin cover in type 1 and type 2 diabetes.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Individualised. Type 2 diabetes: recommended starting dose 10 units once daily, then individually titrated. Type 1 diabetes: once daily in combination with mealtime (short-/rapid-acting) insulin, individually titrated

Route: Subcutaneous only (thigh, upper arm or abdominal wall) - must NOT be given intravenously (risk of severe hypoglycaemia) or intramuscularly, and must not be used in insulin infusion pumps

Frequency: Once daily, at any time of day but preferably the same time each day; a minimum of 8 hours between injections

Basal insulin analogue; 1 unit degludec = 1 international unit human insulin (= 1 unit insulin glargine 100 units/mL or insulin detemir). Type 2 diabetes: may be given alone or with oral antidiabetics, GLP-1 receptor agonists and/or bolus insulin. Transfer - type 2 diabetes: unit-to-unit from the previous basal insulin (consider a 20% dose reduction if switching from twice-daily basal insulin or from insulin glargine 300 units/mL); type 1 diabetes: consider a 20% reduction of the previous basal dose. Adding a GLP-1 receptor agonist: start (or reduce Tresiba) at a 20% lower dose to minimise hypoglycaemia. Elderly and renal/hepatic impairment: can be used - intensify glucose monitoring and individualise the dose. Can be used in adolescents and children from 1 year of age; no clinical experience below 1 year and no data on flexible dosing time in children.

Dose adjustments

Renal

Can be used in renal (and hepatic) impairment; intensify glucose monitoring and adjust the dose on an individual basis.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to insulin degludec or to any excipient

Side effects

Hypoglycaemia (very common)
Injection-site reactions (common)
Lipodystrophy at injection sites (uncommon); cutaneous amyloidosis
Peripheral oedema (uncommon)
Hypersensitivity and urticaria (rare); allergic reactions may rarely be life-threatening

Interactions

Drugs that may increase hypoglycaemia risk: oral/other antidiabetic agents, ACE inhibitors, angiotensin II receptor blockers, disopyramide, fibrates, fluoxetine, MAO inhibitors, pentoxifylline, pramlintide, salicylates, octreotide, sulfonamide antibiotics
Drugs that may reduce the glucose-lowering effect: corticosteroids, diuretics, danazol, oestrogens and oral contraceptives, thyroid hormones, growth hormone (somatropin), sympathomimetics, atypical antipsychotics, protease inhibitors
Anti-adrenergic drugs (beta-blockers, clonidine, guanethidine, reserpine) may reduce or mask the warning signs of hypoglycaemia

Clinical monograph

How it works

After injection it forms soluble multihexamers in the subcutaneous tissue that slowly release monomers, producing a flat, prolonged and consistent glucose-lowering effect.

Prescribing in practice

High-strength preparations exist and look-alike confusion can cause dangerous overdose, so prescribe units in words and specify the exact strength and device.
Its long duration gives flexibility in injection timing but means dose changes take several days to reach full effect.
Hypoglycaemia remains a risk; review concurrent glucose-lowering therapy against current prescribing references.

Monitoring

Monitor fasting and overall blood glucose and HbA1c, titrating slowly because the full effect of changes is delayed.

Counselling the patient

Take it once daily; if needed the time can vary slightly day to day but keep a regular routine.
Carry fast-acting carbohydrate and know the signs of hypoglycaemia.
Check you have the correct strength and device, and never share pens.

Evidence & guidelines

Insulin degludec provides stable basal cover with low nocturnal hypoglycaemia, as shown in its trial programme, and is recommended within NICE diabetes guidance.

Reference: NICE NG17; DEVOTE Trial (NEJM 2017); MHRA Insulin Safety Alert; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways