Invokana and Invokamet are two diabetes medications that according to studies can increase the risk of amputation. In fact, the FDA has warned of diabetes and amputations linked to these and several other medications.

In May 2017, the U.S. Food and Drug Administration (FDA) revealed that two large clinical trials identified canagliflozin drugs (Invokana, Invokamet, Invokamet XR) as diabetes medications linked to amputation.

Invokana and other canagliflozin diabetes drugs are part of the drug class SGLT2 inhibitors. The medications lower blood sugar in type-2 diabetes patients by processing excess sugar through urine.

The CANVAS (Canagliflozin Cardiovascular Assessment Study) and CANVAS-R (A Study of the Effects of Canagliflozin on Renal Endpoints in Adult Participants With Type 2 Diabetes Mellitus) clinical trials prompted the announcement after revealing that patients on the drugs were twice as likely to have leg and foot amputations.

Results of the CANVAS trial showed that, over the course of a year, 5.9 out of every 1,000 canagliflozin patients had an amputation compared to 2.8 out of every 1,000 placebo patients. The CANVAS-R trial showed similar results over the course of a year, with 7.5 out of every 1,000 canagliflozin patients having an amputation and 4.2 out of every 1,000 placebo patients needing an amputation.

The FDA notes that individuals with peripheral vascular disease, neuropathy (nerve damage), diabetic foot ulcers, and a history of amputation may be at a higher risk for amputations while taking Invokana.

New warnings have been added about diabetes and amputation to the labeling for Invokana, Invokamet, and Invokamet XR. Consumers may still be stressed about the risk. However, this does not mean that patients should stop taking the medications without doctor supervision.

“Patients taking canagliflozin should notify your health care professionals right away if you develop new pain or tenderness, sores or ulcers, or infections in your legs or feet. Talk to your health care professional if you have questions or concerns. Do not stop taking your diabetes medicine without first talking to your health care professional,” the FDA stated in their announcement.

There is already a link between diabetes and amputations. Untreated diabetes can have serious consequences, including blindness, nerve damage, kidney damage, heart disease, and more. Therefore, the agency stressed the importance of speaking with a doctor before stopping the diabetes medications that may increase the risk of amputations.

The FDA also recommends that patients on the medications seek medical attention at the first signs of diabetic foot ulcers and take good care of their feet to prevent these sores.

The Invokana website provides several tips for diabetes patients in order to avoid diabetic foot ulcers and their complications. Their recommendations include:

• Check your feet daily: wash and dry feet then apply lotion; keep toenails trimmed; regularly check for cuts, sores, blisters, swelling, or breaks between the toes.
• Get an annual foot exam: doctors should regularly check the feet of diabetes patients, especially if they have foot problems.
• Choose your shoes wisely: running shoes may be the best option; thoroughly try on the shoes and test them in order to make sure they fit and are supportive enough; replace shoes frequently.
• Keep blood flowing: poor blood flow can lead to nerve issues which can in turn make it harder to detect foot injuries.
• Protect your feet from injury: “A little prevention – and pampering – pays off”.

Even when patients work to prevent diabetic foot ulcers, they may still be at risk for an amputation – especially if they are taking diabetes medications linked to amputations.