Lantus vs humalog?

In short:
- Lantus (insulin glargine) is a long-acting basal insulin.
- Humalog (insulin lispro) is a rapid-acting bolus insulin for meals (and corrections).

Key differences
- Onset/duration:
- Lantus: starts in 1–2 hours, provides a steady “basal” level for about 24 hours (flat action, little to no peak).
- Humalog: starts in about 15 minutes, peaks in 30–90 minutes, lasts ~3–5 hours.
- How they’re used:
- Lantus: used once daily (sometimes twice) to supply background insulin.
- Humalog: used before meals to cover carbohydrate intake and to correct high readings.
- Dosing pattern:
- Most people on basal-bolus therapy use both: Lantus for basal (background) and Humalog before meals.
- Mixing in a syringe:
- Do not mix Lantus with any other insulin in the same syringe.
- Humalog can be mixed with some insulins like NPH in the same syringe (if prescribed), but you should follow your prescriber’s instructions.
- Formulations:
- Lantus is long-acting insulin; available as U-100 (and there’s a related product called Basaglar as a biosimilar).
- Humalog is rapid-acting; available in U-100 and U-200 concentrations (the U-200 is a special KwikPen).
- Who uses them:
- Lantus: for steady baseline glucose control.
- Humalog: for mealtime glucose spikes.
- In many regimens for type 1 or advanced type 2 diabetes, both are used together.

Practical notes
- If you’re considering starting one or both, your doctor will tailor the dose to your blood glucose, meals, and activity.
- If you use a pump, it typically uses rapid-acting insulin (like Humalog) rather than a long-acting one.
- Storage: unopened vials/pens go in the fridge; in-use pens/vials usually stay at room temp for a few weeks (check product guidelines).
- Side effects: the main risk with both is low blood sugar (hypoglycemia); weight gain can occur.

If you’d like, tell me:
- Your diabetes type and current regimen (if any)
- Whether you’re aiming for basal-only vs. meal-time coverage
- Any concerns (hypoglycemia risk, injections, cost)

I can tailor a simple, example plan or explain dosing concepts in more detail.