Diabetes Drug & Supplement Compendium

BOTTOM LINE

The first-line treatment almost every diabetic cat can use. If remission is the goal, glargine-type insulin started right after diagnosis, plus low-carb wet food and home glucose checks, is the best-supported path today.

Most feline diabetes resembles human type 2 — too little insulin, and insulin that works poorly. Injections make up the shortfall, bring glucose down, and buy exhausted beta cells time to rest and recover. When that recovery happens, glucose holds without insulin — remission — which is why which insulin you choose and how soon you start shapes the outcome. Today's standard is a long-acting insulin twice daily, 12 hours apart, and in newly diagnosed cats glargine achieved more remissions than PZI or lente. Start low and adjust slowly, every 1–2 weeks — rushed dose increases are the shortest road to hypoglycemia. The table below compares the types.

FACTS

Research

In newly diagnosed cats (Marshall 2009), remission within 16 weeks was glargine 8/8 · PZI 3/8 · lente 2/8 · glargine + low-carb + home monitoring reached 64%, and 84% when started within 6 months of diagnosis (Roomp & Rand 2009)

Track record

Insulin discovered 1921 · glargine since 2000 (human) · PZI licensed for cats 2009 (US) · first-line in the AAHA feline

Caution

Mixing U-40 and U-100 syringes puts the dose off by 2.5× · on days without food, follow the agreed rule (empty stomach + insulin = hypoglycemia) · if unsure it went in, never re-inject · dose changes are made with your vet, using your records

TYPES & INGREDIENTS

• Glargine (Lantus etc.)Long-acting · strongest remission evidence · clear solution · U-100
• Glargine U300 (Toujeo)3× concentrated, flatter curve — 44% remission in newly diagnosed cats in a small study
• Detemir (Levemir)Long-acting like glargine · U-100 · less feline data
• PZI (ProZinc)Licensed for cats · cloudy suspension (roll to mix) · U-40
• Lente (Caninsulin·Vetsulin)Intermediate-acting · U-40 · shorter duration in cats

Read the full fact-check →

BOTTOM LINE

A legitimate option for a cat that is newly diagnosed, insulin-naive, ketone-free and otherwise healthy. If remission is the top priority, the current evidence still favors insulin.

Instead of adding insulin, this drug flips the idea — it blocks the kidney's glucose-reabsorption channel (SGLT2) so excess sugar leaves in the urine. Once a day by mouth, and because it discards sugar rather than forcing it down, hypoglycemia risk is structurally low. Its one price is heavy: ketoacidosis. The risk jumped in cats with prior insulin use, hence the "new and insulin-naive" rule, and it can occur with normal glucose (euglycemic DKA), so early monitoring watches ketones more than glucose. Being controlled on this drug is not the same as the disease retreating (remission), and its remission rate has not been properly studied. Switching to insulin later is possible, but the reverse is blocked by eligibility — so the first choice matters.

FACTS

Research

In a large randomized trial (SENSATION) it was non-inferior to insulin — 81% in the normal glycemic range at day 180, increased thirst/urination improved in 88% · bexagliflozin also reported over 80% control success

Track record

Bexacat (bexagliflozin tablet) approved in the US, December 2022 — the first SGLT2 drug in veterinary medicine · Senvelg

Caution

Ketoacidosis (DKA) — about 7% in trials, 18.4% in insulin-experienced cats vs 5.1% in newly diagnosed · it can arrive with normal glucose, so ketone checks in the first 2–8 weeks are mandatory · on days your cat will not eat, hold the dose and check ketones first

Read the full fact-check →

BOTTOM LINE

Not routine care yet — a card to discuss with a specialist for cats that need weight loss or have a realistic shot at remission. No product is approved for cats.

The GLP-1 family that transformed human diabetes and obesity care (the Ozempic/Wegovy family) mimics a gut hormone that boosts insulin release after meals and slows appetite and stomach emptying. In cats, small studies adding exenatide to insulin reported better control with lower insulin needs and less weight gain. Possible beta-cell protection draws interest for remission, but there is no approved product and the evidence is small. "Ozempic for cats" is still horizon, not news — the best move today is to use everything that has already arrived: insulin, low-carb food and home monitoring.

FACTS

Research

Small feline studies adding it to insulin reported better control, lower insulin needs, less glucose variability and less weight gain · a 2025 international feline consensus: not routine, consider case by case

Track record

No feline-approved product — research and specialist use · once-monthly long-acting forms are being studied in cats

Caution

Vomiting and reduced appetite are common side effects · studied as an add-on to insulin, not alone · never improvise with human injectables

Read the full fact-check →

BOTTOM LINE

If injections are truly impossible, eligible cats should look at SGLT2 first today. If your cat is already on glipizide, re-evaluate response and side effects with your vet.

Glipizide is a sulfonylurea that squeezes the pancreas to release more insulin. It works in some cats that still have insulin-making capacity, but it does so by pushing already exhausted beta cells harder — the opposite direction from remission. Current guidance therefore keeps it as a last resort when injections are impossible. Metformin, the backbone of human type 2 care, showed little effect in cats. Since feline oral drugs (SGLT2) were approved from 2022, homes that need "a pill instead of a needle" have moved there.

FACTS

Research

Glipizide helps only a little over 40% of cats (ISFM 2015) and may wear out remaining beta cells, so the AAHA 2018 guideline reserves it for owners who refuse insulin · metformin controlled only 1 of 5 diabetic cats (Nelson 2004)

Track record

Used in the 1990s–2000s for homes that could not inject · role shrank after SGLT2 approvals (2022–2023)

Caution

Vomiting, raised liver enzymes and hypoglycemia reported · do not drag on without a response — it can eat into the remission window (first 6 months)

Read the full fact-check →

BOTTOM LINE

There is no basis to expect it to treat diabetes. If you still want to give it, add hypoglycemia checks for cats on insulin, and always tell your vet.

Chromium is a trace mineral said to help insulin signal into cells, so it is common in human blood-sugar supplements. In cats, one small study found slightly better glucose tolerance in healthy cats given chromium, but no study shows better glucose or remission in diabetic cats, and human results are mixed. What reliably works for diabetic cats is low-carb wet food and timely insulin — supplements cannot take that place.

FACTS

Research

One study in healthy cats (Appleton 2002) found slightly better glucose tolerance, another found none (ISFM 2015) — no study in diabetic cats

Track record

Decades as a human supplement · no basis for use in feline diabetes

Caution

Beware high-dose human blends with extra ingredients · if it does anything alongside insulin, hypoglycemia is possible

BOTTOM LINE

Do not give it. It is common in human blood-sugar, antioxidant and nerve supplements — check the label before sharing any human product.

Alpha-lipoic acid is an antioxidant widely sold to people for diabetic neuropathy and blood-sugar support. The problem is that cats tolerate it unusually poorly — a feline study found it about 10× more toxic than reported in humans, dogs or rats, with liver damage and neurological signs. No study shows benefit in feline diabetes. Diabetic neuropathy (walking on the hocks) usually improves once glucose is controlled — that is the real treatment.

FACTS

Research

A feline toxicity study (Hill 2004): about 10× more toxic in cats than reported in humans, dogs or rats · no study of benefit in feline diabetes

Track record

Used for human diabetic neuropathy · feline toxicity reported in 2004

Caution

Risk of liver damage, neurological signs and hypoglycemia · check human blends for "alpha-lipoic acid, thioctic acid, ALA"

BOTTOM LINE

No basis to recommend them for diabetic cats. If they did work, they could stack with insulin and cause hypoglycemia — "natural" does not mean safe here.

These are the classic human blood-sugar ingredients — cinnamon extract, bitter melon, berberine and vanadium. Human evidence is mixed or small, there are no feline diabetes studies for cinnamon, bitter melon or berberine, and vanadium has only old small reports. Cats process drugs in the liver differently from people, so ingredients that are fine for humans can harm cats (alpha-lipoic acid is the classic case). What actually moves a diabetic cat's glucose is low-carb food and insulin — or SGLT2 if eligible.

FACTS

Research

No feline studies for cinnamon, bitter melon or berberine · vanadium has only a small 1999 conference abstract (Fondacaro) reporting lower insulin needs, with unknown long-term safety

Track record

Human folk and supplement use · no basis for feline diabetes

Caution

May stack with insulin into hypoglycemia · berberine affects liver metabolism of other drugs · check blends for alpha-lipoic acid (toxic to cats) · vanadium is a heavy metal

BOTTOM LINE

Neuropathy usually improves once glucose is controlled. Methylcobalamin is fairly safe and can be added after talking with your vet, but it cannot replace glucose control.

High glucose damages nerves in some diabetic cats, so they walk on their hocks (a plantigrade stance). Methylcobalamin is the nerve-active form of vitamin B12, used as support in human diabetic neuropathy and empirically by some feline clinics. But there is no controlled feline study, and the surest treatment is glucose control — once controlled, gait often returns over weeks to months. Whether blood cobalamin is actually low is checked separately with a test.

FACTS

Research

Extrapolated from human diabetic neuropathy research · no controlled study in feline diabetic neuropathy (case reports only)

Track record

Used as human neuropathy support · used empirically in some feline clinics

Caution

Low blood B12 is a separate question — confirm with a test · check ingredients and dose in human B-complex products