Side effects
Foundayo and low blood sugar
On its own, rarely. In the trial of people with type 2 diabetes, low blood sugar was reported by 2 percent on Foundayo against 0.2 percent on placebo. With a sulfonylurea it was 7 percent. In people without diabetes the label found it in 0.6 percent. The Medication Guide lists the signs and says the risk is higher with insulin or a sulfonylurea.
DM, the one who read the label
Sources checked Oct 7, 2026
Published Oct 11, 2026
Updated Oct 7, 2026 · 1 min read
The short answer
On its own, rarely. In the trial of people with type 2 diabetes, low blood sugar was reported by 2 percent on Foundayo against 0.2 percent on placebo. With a sulfonylurea it was 7 percent. In people without diabetes the label found it in 0.6 percent. The Medication Guide lists the signs and says the risk is higher with insulin or a sulfonylurea.
What the label says
The label reports two trials separately, because the answer depends on who is asking.
In the trial of people with type 2 diabetes, blood glucose below 54 mg/dL was reported in 2 percent of people on Foundayo and 0.2 percent on placebo. Among those also taking a sulfonylurea, it was 7 percent, against 0.5 percent of those not taking one. One person on 5.5 mg had a severe low; nobody on placebo did.
In the trial of people without diabetes, the label found a glucose reading below 54 in 0.6 percent of people on Foundayo and none on placebo, with no severe cases.
What the Medication Guide adds
From the labelYour risk for getting low blood sugar may be higher if you use FOUNDAYO with medicines that can cause low blood sugar, such as an insulin or sulfonylurea.
Then the list of signs: dizziness or light-headedness, blurred vision, anxiety, irritability or mood changes, sweating, slurred speech, hunger, confusion or drowsiness, shakiness, weakness, headache, fast heartbeat, feeling jittery.
What people actually do
The question comes from two groups. People with type 2 diabetes who already carry a meter and know the feeling, and for whom the label's answer is a review of the insulin or sulfonylurea dose with the prescriber before starting. And people without diabetes who feel shaky in the afternoon and wonder. For them the label's number is small, and the more common explanation described on the forums is a day with almost no food, which is its own problem on a drug that quiets appetite.
Either way the signs are the same list, and a low that keeps coming back is a call.
Oolite's journal keeps the days, and a symptom that repeats is visible as a line. It does not read glucose and does not judge a symptom; the meter and the prescriber do.
Questions people ask
I do not have diabetes. Can Foundayo give me a low?
The label reports glucose below 54 mg/dL in 0.6 percent of people without diabetes on Foundayo and none on placebo, with no severe cases. Rare, not zero.
I take metformin. Does that change the risk?
The label singles out insulin and sulfonylureas as the medicines that raise the risk. It does not name metformin in that warning. Your prescriber knows your list.
What are the signs?
The Medication Guide lists dizziness or light-headedness, blurred vision, anxiety or mood changes, sweating, slurred speech, hunger, confusion or drowsiness, shakiness, weakness, headache, fast heartbeat, feeling jittery.
Should my other diabetes medicines be changed when I start?
The label says the risk is higher with insulin or a sulfonylurea, which is the prescriber's cue to review those doses. Ask before the first tablet, not after the first low.
Sources
- Foundayo prescribing information, Eli Lilly, §6.1, revised 07/2026 · Trial 2 (type 2 diabetes): hypoglycemia (glucose below 54 mg/dL) 2 percent vs 0.2 percent; 7 percent with sulfonylurea vs 0.5 percent without; Trial 1 (no diabetes): 0.6 percent vs 0, no severe cases.
- Foundayo Medication Guide, Eli Lilly, issued 07/2026 · Low blood sugar: risk higher with insulin or sulfonylurea; list of signs and symptoms.
Sources checked Oct 7, 2026. This page is information, not medical advice: read the medical disclaimer, and talk to your prescriber or pharmacist about your own treatment.
Written by
DM, the one who read the label
I make Oolite. I read every label revision the day it comes out and rewrite these answers when they change.
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