SGLT2 ‘Sick Day Rules’ for Jardiance and Farxiga: Stay Safe During Illness or Fasting

Quick take (save or screenshot)

Pause Jardiance / Farxiga if you’re vomiting, have bad diarrhea/fever, can’t keep fluids down, before surgery, or during a long fast.
Keep taking your long-acting insulin unless your clinician tells you otherwise.
Sip fluids often and include some carbs to prevent ketone buildup.
Check blood sugar every 3–4 hours; check ketones if you feel unwell.
Go to urgent care for positive/rising ketones, nonstop vomiting, fast/deep breathing, chest pain, confusion, or severe dehydration.

Why this matters

SGLT2 inhibitors, like Jardiance and Farxiga, are great for type 2 diabetes, heart failure, and kidney protection. But when you’re sick, dehydrated, or fasting, they can raise the risk of a rare problem called euglycemic DKA, dangerous acid buildup in the blood even when your sugar isn’t very high. Knowing a few simple rules keeps you safe.

What is euglycemic DKA?

“DKA” means your body is making too many ketones, turning your blood acidic. With SGLT2 medicines, this can happen even if your glucose is normal or only a little high, especially during illness, dehydration, strict low-carb eating, fasting, or around surgery.

The core sick-day rules (plain-English checklist)

Do

Pause your SGLT2 (Jardiance/Farxiga) if you’re vomiting, have bad diarrhea/fever, can’t keep fluids down, feel dehydrated or faint, are admitted to hospital, or before a planned procedure/long fast.
Keep your long-acting insulin going (unless your clinician says otherwise). It helps stop ketone production.
Hydrate with frequent small sips: water, oral rehydration/electrolyte drinks, broths.
Include some carbs (toast, crackers, soup, oral glucose if needed) to reduce ketones when you’re eating less.
Check glucose every 3–4 hours. If you feel worse, also check ketones (blood meters are best; urine strips are okay if that’s what you have).
Call your clinic early if ketones are positive, you can’t keep fluids down, or your symptoms are getting worse.

Don’t

Don’t stop long-acting insulin on your own.
Don’t take extra ibuprofen/aspirin/naproxen without checking, these can raise bleeding/kidney risks when dehydrated.
Don’t “tough it out” with nonstop vomiting, fast/deep breathing, chest pain, confusion, or severe weakness, get urgent help.

Farxiga / Dapagliflozin for $32.99

Fluids, carbs, and monitoring (the simple plan)

Aim for a few sips every 5–10 minutes if nauseated.
Choose electrolytes (oral rehydration solution, diluted sports drinks) plus gentle carbs (crackers, toast, rice, applesauce, broth with noodles).
Glucose checks: every 3–4 hours while sick.
Ketone checks: any time you feel worse, are not eating, or sugars are drifting up—blood ketone meters give the clearest picture.

Surgery and procedures

For planned procedures (including colonoscopy prep), most teams ask patients to stop SGLT2 meds 3–4 days before and restart only when eating and drinking normally again. Follow the written plan from your surgeon/endoscopy team.

Fasting (religious or medical)

Fasting increases ketosis. Many clinicians recommend holding SGLT2 medicines during the fast, prioritizing hydration during non-fasting hours and not doing strict low-carb at the same time. Make a plan with your clinician ahead of time.

When is it safe to restart Jardiance/Farxiga?

Use this rule of thumb (and your clinician’s advice):

You’ve had 24–48 hours of normal eating and drinking.
No vomiting/diarrhea; fever has settled.
You feel re-hydrated; ketones are negative/trace if you checked.
Your care team says it’s okay to restart.

Who has higher risk for euglycemic DKA?

Recent surgery or acute illness
Prolonged fasting or very low-carb/keto diets
Relative insulin shortage (long-standing diabetes, missed insulin, or very low insulin doses)
Dehydration, heavy alcohol use, or infections

If one or more apply to you, be extra cautious and keep a written plan handy.

What to pack in a simple sick-day kit

Blood ketone meter/strips (or urine ketone strips if that’s what you can get)
Electrolyte packets or ready-to-drink solutions
Quick carbs (glucose tabs/gel, crackers, broth)
Thermometer
A current medication list and clinic/emergency contacts
Your printed sick-day plan (when to hold, when to restart, when to call/go).

FAQs

My sugar is only 150 mg/dL—could it still be DKA?
Yes. With SGLT2 meds, DKA can happen with normal or only mildly high glucose. Ketones tell the story.

Are urine ketone strips okay?
They’re better than nothing, but blood ketone meters are more reliable, especially on SGLT2 therapy.

I take an SGLT2 for heart failure/CKD but don’t have diabetes. Do these rules apply?
Yes. The pause/monitor/restart plan still applies during illness, fasting, or before procedures.

When exactly do I restart after surgery?
Usually when you’re eating and drinking normally again, and your team gives the green light.

Can I stay on a keto diet with an SGLT2?
Keto plus SGLT2 can raise ketosis risk. Discuss safer options or adjustments with your clinician.

Bottom line

When you’re sick, dehydrated, or fasting, pause the SGLT2, keep long-acting insulin, hydrate with some carbs, check sugars and ketones, and restart only after you’re fully back to normal. A small plan goes a long way toward preventing a big problem.

Disclaimer: This article is for informational purposes only and not medical advice. Consult a licensed healthcare provider before starting or changing medications. Use reputable, licensed pharmacies to ensure safety. This guide is educational and doesn’t replace your clinician’s advice. Always follow the plan you and your healthcare team create for your specific situation.