Once-weekly insulins are long-acting basal insulins you inject one time per week instead of every day. Two are now FDA-approved for adults with type 2 diabetes: Awiqli (insulin icodec, Novo Nordisk) and Onswik (insulin efsitora alfa, Eli Lilly). They control blood sugar about as well as daily basal insulin with 52 injections a year instead of 365. They are not approved for type 1 diabetes.
Basal (background) insulin keeps blood sugar steady between meals and overnight. Until 2026, every basal insulin — Lantus, Basaglar, Toujeo, Tresiba, Levemir — had to be injected at least once a day. Awiqli and Onswik are engineered to bind to proteins in the blood and release insulin slowly over the whole week. That lets one injection cover seven days. Learn more about how background insulin works in our basal insulin guide.
The Two Once-Weekly Insulins
| Awiqli | Onswik | |
|---|---|---|
| Generic name | Insulin icodec-abae | Insulin efsitora alfa-gobe |
| Maker | Novo Nordisk | Eli Lilly |
| FDA approval | March 2026 (available in the US since August 2026) | September 2026 (pens expected in the coming months) |
| Approved for | Adults with type 2 diabetes | Adults with type 2 diabetes |
| Pen | FlexTouch, 700 units/mL; dials in 10-unit steps, up to 700 units per injection | KwikPen, 500 units/mL (5-unit steps, up to 400 units) or 1,000 units/mL (10-unit steps, up to 800 units) |
| How often | Once a week, same day each week | Once a week, same day each week |
Who Might Benefit?
- Adults with type 2 diabetes who are starting insulin and want as few injections as possible
- People on daily basal insulin who forget doses or find daily shots a burden
- Patients who rely on a family member, caregiver, or home health nurse to give injections — one weekly visit is far easier than seven
- People with needle anxiety who would rather inject once a week
Once-weekly insulin may be a poorer fit for people with type 1 diabetes (not approved), people whose insulin needs change quickly (for example, during steroid treatment, pregnancy, or frequent illness), and people with a history of frequent or severe low blood sugar. Because a weekly dose stays in the body for days, it can't be quickly “turned off” if you get sick or stop eating.
How Dosing Works
Your endocrinologist will calculate your weekly dose. In general:
- Starting insulin for the first time: Awiqli usually starts at 70 units once weekly. Onswik is started at a fixed weekly dose set by your provider (100 units weekly was used in clinical trials)
- Switching from daily basal insulin: take your first weekly dose the day after your last daily dose. With Awiqli, the first week's dose is usually larger (a one-time “loading” dose) to get insulin levels up quickly, and then it drops to the regular weekly amount
- Adjusting: the dose is changed no more than once a week, based on your fasting blood sugar or CGM readings
- Same day each week: pick a day you'll remember (many people link it to a weekly routine). Set a phone reminder
If You Miss a Dose
If it has been 4 days or less since your scheduled day, take the missed dose as soon as you remember, then follow the schedule your provider gives you. If more than 4 days have passed, follow your insulin's specific instructions — call us if you're unsure. Check your blood sugar more often for the next several days. Never take two weekly doses close together; if you accidentally take an extra dose, call our office and skip the next week's dose unless told otherwise.
⚠️ Concentrated-insulin safety: Both once-weekly insulins are much stronger per mL than standard U-100 insulin. Always dial your dose in units on the pen. Never draw insulin out of the pen with a syringe, never mix it with other insulins, and never use it in an insulin pump. Do not dial the pen's maximum dose unless you were specifically told to.
How Well Do They Work?
Both insulins were tested in large clinical trial programs (ONWARDS for Awiqli, QWINT for Onswik) involving thousands of adults with type 2 diabetes. In these studies, once-weekly insulin lowered A1c as well as or slightly better than daily glargine (Lantus) or degludec (Tresiba). For example, in ONWARDS 1, insulin-naive adults on Awiqli lowered their A1c by about 1.55 percentage points, compared with about 1.35 on daily glargine.
Low Blood Sugar (Hypoglycemia)
Low blood sugar is the most common side effect of any insulin. In some trials, once-weekly insulin caused slightly more low blood sugar episodes than daily insulin, although serious episodes were uncommon. With Awiqli, lows were most likely 2 to 4 days after the injection, when insulin levels are highest. Using a continuous glucose monitor (CGM) is a good way to spot patterns during the first weeks. Know the signs of a low and how to treat it — see our hypoglycemia guide.
🤒 Sick days: A weekly insulin dose keeps working for days, even if you can't eat. If you're vomiting, not eating, or sick, check your blood sugar more often and call us early. Do not skip or change a weekly dose on your own without talking to your care team. See our sick-day rules.
Other possible side effects include injection-site reactions, weight gain, and low potassium. As with other insulins, combining once-weekly insulin with pioglitazone (a TZD) can cause fluid retention and may worsen heart failure. Tell us if you notice swelling or sudden weight gain.
Cost and Coverage
Because these insulins are brand new, insurance coverage is still being set up. Some plans may require prior authorization or that you try a daily basal insulin first. Our team can help check your coverage before you switch.
Key Takeaways
- Awiqli (icodec) and Onswik (efsitora) are the first basal insulins injected just once a week
- Both are approved only for adults with type 2 diabetes, not type 1
- They lower A1c about as well as daily Lantus or Tresiba with 52 injections a year instead of 365
- Both are concentrated: always dial in units, and never draw from the pen with a syringe
- Low blood sugar can happen several days after the injection, so CGM and sick-day planning matter
- If you miss a dose by 4 days or less, take it as soon as possible; otherwise call us
Our Team Can Help
All five of our providers diagnose and manage endocrine conditions. Book with any member of our team:
Book an Appointment → or call 832-968-7003