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Cat Insulin Dosage Calculator — Glargine (Lantus) & PZI Starting Dose

Calculate the AAHA-guideline starting insulin dose for a diabetic cat. Rounded to 0.5 U precision for accurate feline dosing.

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Starting dose
1units per dose · Every 12 hours (BID) with meals
Calculated: 1.13 U · AAHA first-choice for cats. U-100 syringes.

Syringe match: U-100

Lantus (U-100) is U-100 concentration. Use U-100 syringes only. Mismatched syringes cause dangerous dosing errors.

Starting dose only. Cats may go into diabetic remission with early insulin therapy + low-carb diet. Monitor BG curves weekly initially.

Frequently Asked Questions

What is the starting insulin dose for a diabetic cat?

Per AAHA 2018 guidelines: glargine (Lantus) or PZI (ProZinc) at 0.25 U/kg every 12 hours, rounded DOWN to 0.5 U increments. A 5 kg cat starts at 1 unit twice daily.

What is the best insulin for cats?

Glargine (Lantus U-100) is AAHA first-choice. PZI (ProZinc U-40) is second choice. Levemir is sometimes used for cats unresponsive to glargine. Avoid NPH and Vetsulin in cats — too short-acting.

Can diabetic cats achieve remission?

Yes. 30-50 % of cats diagnosed early and treated with insulin + low-carb diet (≤ 7 % carb like Purina DM or Hill's m/d) achieve diabetic remission within 6-12 months.

Sources & References

  1. [1]
    AAHA 2018 Diabetes Management Guidelines — American Animal Hospital Association
  2. [2]
    Feline diabetic remission — American Association of Feline Practitioners
  3. [3]

Common mistakes to avoid

  • Changing insulin dose without glucose curve — always get a 12h glucose curve before adjusting.
  • Confusing U-40 and U-100 syringes — ProZinc is U-40; Glargine is U-100. Wrong syringe = dangerous dosing error.
  • Skipping a dose if the cat missed a meal — give half-dose instead (consult your vet for your cat's protocol).

When to call the vet immediately

  • Weakness, staggering, seizure — hypoglycemia. Apply corn syrup to gums, rush to ER.
  • Deep rapid breathing + fruity breath — DKA (diabetic ketoacidosis), emergency.

Pro tips

  • Home glucose monitoring (AlphaTRAK 2 or a FreeStyle Libre CGM) lets you catch trouble early.
  • Refrigerate insulin always, but never freeze. Gently roll (don't shake) before each dose.
  • Low-carb canned diet (<7% carbs) is often more important than the dose itself for remission.