Bexagliflozin (Brenzavvy) Side Effects: What to Expect and When to Call Your Doctor

Like all medications, bexagliflozin (Brenzavvy) can cause side effects. Most are manageable and will improve over time. But some require prompt medical attention. This guide walks you through what to expect and what to watch out for when starting Brenzavvy.

Common Side Effects of Brenzavvy (Bexagliflozin)

These side effects occurred more often in patients taking Brenzavvy than in those taking placebo in clinical trials. They are generally mild to moderate:

Urinary tract infections (UTIs) — One of the most common side effects. Symptoms include burning with urination, frequent urges to urinate, and cloudy or strong-smelling urine. Contact your doctor promptly if symptoms develop, as UTIs can become serious (see below).

Genital yeast infections — Increased glucose in urine promotes yeast growth in the genital area. In women: vaginal discharge, itching, or odor. In men: redness, rash, or pain around the penis. Good hygiene helps reduce risk.

Increased urination — Expected as the kidneys excrete more glucose. This typically improves within a few weeks. Stay well hydrated.

Dehydration — Loss of water through increased urination can cause dehydration. Signs include dizziness, lightheadedness, and decreased urination. Drink plenty of fluids, especially in hot weather or during exercise.

Hypoglycemia (low blood sugar) — Only likely if you're also taking insulin or a sulfonylurea (like glipizide or glimepiride). Symptoms: shakiness, sweating, confusion, rapid heartbeat. Your doctor may lower your dose of insulin or sulfonylurea.

Serious Side Effects: When to Call Your Doctor Immediately

The following are rare but serious. Stop taking Brenzavvy and seek medical attention right away if you experience:

Diabetic ketoacidosis (DKA) — A life-threatening condition. Symptoms include nausea, vomiting, abdominal pain, fruity-smelling breath, tiredness, and difficulty breathing. DKA can occur even with normal or near-normal blood sugar in patients taking SGLT2 inhibitors. Risk is higher during illness, fasting, surgery, or alcohol use.

Fournier's gangrene — A rare but life-threatening infection of the genital and rectal area (necrotizing fasciitis). Symptoms: severe pain, tenderness, swelling, redness, or warmth in the genital area accompanied by fever. Requires immediate emergency care.

Serious urinary tract infections — Kidney infections (pyelonephritis) or sepsis from UTIs have been reported with SGLT2 inhibitors. Symptoms: fever, back/side pain, nausea, vomiting in addition to UTI symptoms. Requires prompt antibiotic treatment.

Severe hypotension (low blood pressure) — Can occur with dehydration, especially in elderly patients or those on diuretics. Symptoms: dizziness, fainting, or feeling lightheaded when standing.

Lower limb amputation risk — SGLT2 inhibitors, including Brenzavvy, have been associated with an increased risk of lower limb amputations, particularly in patients with peripheral vascular disease, neuropathy, or a history of prior amputation. Report any new foot pain, sores, tenderness, or infections immediately.

Acute kidney injury — Dehydration from Brenzavvy can stress the kidneys. Monitor for reduced urine output, swelling in legs or ankles, unusual fatigue, or shortness of breath.

Allergic reactions — Rare. Signs: hives, swelling of the face, lips, tongue, or throat, difficulty breathing. Call 911 if you experience these symptoms.

Side Effects and Pregnancy

Brenzavvy is not recommended during the second and third trimesters of pregnancy. Animal studies showed adverse kidney effects in developing fetuses. If you are pregnant, planning to become pregnant, or breastfeeding, tell your doctor before starting or continuing Brenzavvy.

Tips to Minimize Common Side Effects

Drink at least 8 glasses of water daily to prevent dehydration and UTIs

Wear breathable cotton underwear and change after exercise to reduce genital yeast infections

Do a daily foot check if you have neuropathy or poor circulation to catch sores early

Tell your surgeon you're on Brenzavvy — it should be stopped at least 3 days before scheduled surgery

Avoid prolonged fasting or extremely low-carb diets while on Brenzavvy, as these increase DKA risk

For more information about drug interactions that may affect side effect risk, see our guide on Brenzavvy drug interactions.

Need help finding Brenzavvy at a pharmacy near you? medfinder calls pharmacies on your behalf to check availability.