Analog Premixed Insulin (NovoLog Mix 70/30, Humalog Mix 75/25): How This Fixed Mix Works and When Telehealth Is Enough

Last updated: August 18, 2026

NovoLog Mix 70/30 (also searched as “70 30 novolog,” “novolog mix 70 30,” and “novolog 70 30 flexpen”) and Humalog Mix 75/25 (also searched as “humalog mix 75 25” and “humalog mix”) are analog premixed insulin products. Each shot holds a fixed share of rapid-acting analog insulin plus a protamine (intermediate) analog. They are not the human 70/30 products Humulin 70/30 or Novolin 70/30. They are not clear meal-only pens such as Humalog, NovoLog, Fiasp, Lyumjev, or Apidra. They are not basal-only pens such as Lantus or Tresiba. Do not swap an analog mix for a human mix, or one analog mix for the other, on your own.

This guide covers how analog premix usually looks and is injected, why the ratio is locked, how FlexPen and KwikPen storage differ, and when a video visit is enough versus when you need labs or the ER. It is educational. It is not a diagnosis or a promise that any specific insulin will be prescribed. Do not change brands, strengths, or units without a clinician.

Want a licensed clinician to review premixed analog insulin or an A1C? Klarity Health has 2,000+ licensed providers. Many visits happen online. See online prescription options or browse conditions.

TLDR

• DailyMed lists NovoLog Mix 70/30 as a mixture of insulin aspart protamine (intermediate analog) and insulin aspart (rapid analog) for subcutaneous use, indicated to improve glycemic control in adult patients with diabetes mellitus. Initial U.S. approval: 2001. It is not recommended for diabetic ketoacidosis. The ratio is fixed, so you cannot separately change the basal piece and the meal piece (DailyMed NovoLog Mix 70/30).
• DailyMed lists Humalog Mix75/25 as a mixture of insulin lispro protamine and insulin lispro for subcutaneous use, indicated to improve glycemic control in adults with diabetes mellitus. Initial U.S. approval: 1999. The ratio is likewise fixed (DailyMed Humalog Mix75/25).
• Both products are U-100 only. NovoLog Mix: 10 mL vial and 3 mL FlexPen. Humalog Mix75/25: 10 mL vial and 3 mL KwikPen. Both should look uniformly white and cloudy after you resuspend them. Do not use a mix that looks clear or has solid particles.
• NovoLog Mix: inject within 15 minutes before a meal starts; in type 2 diabetes the dose may also be given after the meal starts. Humalog Mix75/25: inject within 15 minutes before a meal. Typical schedule for both is twice daily, with each dose meant to cover two meals or a meal and a snack.
• Do not give either product IV. Do not put either product in a pump. Do not mix either product with any other insulin. Never share a FlexPen, KwikPen, needle, or syringe.
• MedlinePlus: insulin lispro suspension (Humalog Mix 75/25 or Mix 50/50) should be injected 15 minutes before a meal. After mixing it should look cloudy or milky. Do not mix the suspension with any other insulin (MedlinePlus insulin lispro).
• Cleveland Clinic analog premix timing many clinicians still quote: Humalog Mix 75/25, Humalog Mix 50/50, and NovoLog Mix 70/30: onset 5 to 20 minutes, peak 1 to 2 hours, duration 10 to 16 hours. Human 70/30 (N plus R) is slower: onset 0.5 to 1 hour, peak 2 to 12 hours, duration 10 to 16 hours (Cleveland Clinic injectable insulin chart).
• Storage from the labels: NovoLog Mix vial 28 days in-use; FlexPen 14 days at room temperature, do not refrigerate the in-use pen. Humalog Mix75/25 vial 28 days in-use; KwikPen 10 days at room temperature only for the in-use pen. Unused refrigerated stock can last until the labeled expiration date.
• Typical home glucose targets many adults use: 80 to 130 mg/dL before meals and under 180 mg/dL two hours after a meal starts. A reading under 70 mg/dL is low. If you are sick and a reading is 240 mg/dL or higher, check ketones (CDC manage blood sugar).
• Medicare covers many telehealth visits from home anywhere in the U.S. through December 31, 2027 (HHS telehealth policy). Seizure, loss of consciousness, chest pain, or blood sugar that will not come up is 911, not a video visit.

What analog premix is trying to fix

Type 1 diabetes means the pancreas makes little or no insulin. Type 2 diabetes means the body resists insulin and often does not make enough of it. Glucose stays in the blood. Over years that raises the chance of heart disease, stroke, kidney disease, nerve damage, and eye disease. NIDDK notes some people with type 2 diabetes can control glucose with food, activity, sleep, and weight change. Many still need pills or insulin. Over time you may need more than one medicine (NIDDK insulin and medicines).

A working pancreas releases a background trickle of insulin and a burst when you eat. Analog premix tries to cover both with one cloudy shot: a rapid analog for the meal and a protamine analog for several more hours. The tradeoff is the lock. DailyMed says the proportions do not allow separate basal versus prandial dose adjustments. If breakfast carbs change but overnight needs do not, you cannot change only one half of the pen.

That is why analog premix is a different product from human 70/30 (Humulin 70/30, Novolin 70/30) and from separate Humalog or NovoLog plus a basal. The carton name matters. “70 30 novolog” is NovoLog Mix. “Novolin 70/30” is human insulin.

Typical home targets the CDC lists for many adults:

• Before a meal: 80 to 130 mg/dL
• Two hours after the start of a meal: under 180 mg/dL

Blood sugar under 70 mg/dL is low. If you are sick and a reading is 240 mg/dL or higher, check ketones. High ketones can signal diabetic ketoacidosis, which is an emergency. DailyMed states NovoLog Mix is not recommended for the treatment of diabetic ketoacidosis. DKA care uses other insulin in a monitored setting.

How NovoLog Mix 70/30 and Humalog Mix 75/25 differ

NovoLog Mix 70/30 is 70% insulin aspart protamine and 30% insulin aspart. Humalog Mix75/25 is 75% insulin lispro protamine and 25% insulin lispro. Both are analog premixes. The percentages are not the same, and the analog molecules are not the same. A unit-for-unit swap is a clinician decision, not a pharmacy assumption.

Cleveland Clinic groups the analog mixes together for timing (5 to 20 minutes / 1 to 2 hours / 10 to 16 hours) and lists human 70/30 separately (0.5 to 1 hour / 2 to 12 hours / 10 to 16 hours). Analog premix usually starts faster than human 70/30 because the rapid piece is lispro or aspart, not Regular.

MedlinePlus groups Humalog Mix 75/25 and Mix 50/50 as insulin lispro suspension and says to inject 15 minutes before a meal. Humalog Mix 50/50 is a different ratio (half and half). This article is about the 75/25 and 70/30 analog products people search most.

How you take analog premix

Both labels say to inspect the suspension, resuspend it until it is uniformly white and cloudy, then inject under the skin. Sites include the abdomen, thigh, upper arm, and buttocks. Rotate sites inside the same region. Do not inject into pits, lumps, scars, or damaged skin.

NovoLog Mix resuspension: roll a vial gently in a horizontal position 10 times. For FlexPen, roll it 10 times, then invert it 10 times so the glass ball travels end to end. Inject right away. The FlexPen dials in 1-unit steps.

Humalog Mix75/25: resuspend immediately before use; it is easier at room temperature. For KwikPen, roll at least 10 times and invert at least 10 times until the suspension is uniformly white and cloudy. The KwikPen dials in 1-unit steps. Use caution if vision is limited and you rely on clicks.

Meal timing:

• NovoLog Mix: within 15 minutes before the meal starts. In type 2 diabetes, the dose may also be given after the meal starts.
• Humalog Mix75/25: within 15 minutes before a meal.

Typical dose pattern on both labels: twice daily, each dose meant to cover two meals or a meal and a snack. Your clinician sets units from your glucose log, A1C, meals, kidneys, liver, activity, and other medicines. Illness, a new meal pattern, or a new activity level can force a change. When you switch from another insulin, DailyMed says a different dose of the mix may be needed, and you should check glucose more often.

Do not give analog premix in a vein. Do not put it in a pump. Do not mix it with any other insulin or diluent. Those rules differ from some clear analog vials, which a clinician may mix with NPH in a syringe.

Storage and in-use life

Keep unused analog premix in the refrigerator at 36°F to 46°F (2°C to 8°C) until the expiration date. Do not freeze it. Do not use it if it has been frozen. Keep it away from heat and light.

NovoLog Mix (DailyMed table):

• 10 mL vial: 28 days at room temperature if unopened; 28 days in-use in the fridge or at room temperature.
• 3 mL FlexPen: 14 days unopened at room temperature; 14 days in-use at room temperature. Do not refrigerate the in-use pen.

Humalog Mix75/25 (DailyMed table):

• 10 mL vial: 28 days unopened at room temperature; 28 days in-use in the fridge or at room temperature.
• 3 mL KwikPen: 10 days unopened at room temperature; 10 days in-use at room temperature only. Do not refrigerate the in-use pen.

Those windows are not interchangeable. A FlexPen is not a KwikPen. Write the open date on the carton.

Safety facts that belong on the carton conversation

Do not use analog premix during hypoglycemia or if you are allergic to the product or an excipient. Hypoglycemia can cause seizures, loss of consciousness, or death. Risk rises when meals, activity, kidney or liver function, or other glucose-lowering drugs change. Beta-blockers and some other drugs can hide warning symptoms.

Never share a FlexPen, KwikPen, needle, or syringe, even if you change the needle. Sharing can pass blood-borne infection.

Check the label every time. Mix-ups between analog premix, human 70/30, and clear analog pens happen because the names look alike.

All insulins can drop potassium. That can be dangerous in people on potassium-lowering drugs. Thiazolidinediones (TZDs) plus insulin can cause fluid retention and worsen heart failure. A clinician may lower or stop the TZD if heart failure appears. See Klarity’s TZD guide if that class is on your list.

Severe allergy, including anaphylaxis, can occur. Stop the product and get emergency care if that happens.

When telehealth is enough, and when it is not

A video visit can often review an A1C, a glucose log, missed meals, new lows after a twice-daily mix, storage questions, and whether analog premix still fits versus a basal-plus-bolus plan or human 70/30. Medicare covers many telehealth visits from home anywhere in the U.S. through December 31, 2027. Plan coverage for the insulin itself still varies. Verify benefits before you assume a copay.

A video visit is not enough for DKA, a seizure, loss of consciousness, chest pain, or glucose that will not rise with your usual rescue plan. Analog premix is not DKA treatment. Call 911.

Labs still matter. Kidney and liver changes can change insulin need. A clinician may order bloodwork at a local lab after a telehealth visit.

Insurance and access

Coverage for NovoLog Mix 70/30, Humalog Mix 75/25, authorized generics, and pens versus vials may vary by plan, formulary tier, and prior authorization. Some plans prefer one analog mix. Some prefer human 70/30. None of that is a guarantee that your plan will pay. Check your formulary and talk with the pharmacy before you leave a gap in doses.

Klarity clinicians can discuss whether a prescription visit is appropriate. They cannot promise a specific brand or that insurance will pay.

Ready to talk through meal-time and overnight coverage in one pen? See online prescription options or browse conditions.

Related Klarity insulin guides

• Human premixed 70/30 (Humulin 70/30, Novolin 70/30)
• Humalog and NovoLog (rapid analog)
• NPH insulin
• Regular insulin

FAQ

Is NovoLog Mix 70/30 the same as Novolin 70/30?

No. NovoLog Mix 70/30 is analog (aspart plus aspart protamine). Novolin 70/30 is human NPH plus Regular. Timing, pens, and substitution rules differ. A clinician has to approve any switch.

Is Humalog Mix 75/25 the same as NovoLog Mix 70/30?

No. One is 75/25 lispro. The other is 70/30 aspart. Both are analog premixes, but they are not automatic substitutes.

Can I put analog premix in a pump?

No. DailyMed says do not use NovoLog Mix or Humalog Mix75/25 in an insulin infusion pump and do not give them intravenously.

Why does the pen look cloudy?

The protamine piece is a suspension. After you roll and invert it, it should look uniformly white and cloudy. If it stays clear or you see clumps or particles stuck to the glass, do not use it.

How long can I keep an opened FlexPen or KwikPen?

NovoLog Mix FlexPen: 14 days at room temperature; do not refrigerate the in-use pen. Humalog Mix75/25 KwikPen: 10 days at room temperature only. Vials for both products: 28 days in-use. Follow the carton if your pharmacy dispensed a different presentation.

Disclaimer

This article is for education. It is not medical advice, a diagnosis, or a coverage promise. Insulin products, doses, and insurance rules change. Verify your prescription, your blood sugar plan, and your benefits with a licensed clinician and your plan before you start, stop, or switch analog premixed insulin.