Gliflozin drugs are a drug class called a sodium-glucose transport protein 2 inhibitor, which when used to treat Type II Diabetes mellitus (the more prevalent kind which is mainly acquired with poor diet and exercise habits, although genetics can play a role too). The mechanism by which Gliflozin drugs manage diabetes is that they allow for the passage of glucose through the kidneys through excretion. Unfortunately for those suffering from this disease, one of the drugs in this class, trade name Invokana, also known as canagliflozin, increases the risk of amputation by a ratio of roughly two to one in a clinical trial conducted by the Food and Drug Administration over the course of a calendar year. Amputation is not uncommon in diabetes sufferers with the medical reason for this being that Diabetes (Type I or Type II) leads to peripheral artery disease (PAD) which reduces blood flow to the feet and lower legs. The most common amputations are, not coincidentally, toes, and legs below the knee due to necrosis, in which tissues die from a lack of blood flow which leads to gangrene and sepsis, painful and deadly infections to which the amputations are the only recourse.
It is unclear at this time how Invokana contributes to these conditions but rather than wait to find out the FDA has already taken the drastic step of ordering drug manufacturer Johnson & Johnson to put a box warning on the drug. Also called a “black box warning” the FDA states the official purpose of these warnings to be “to call attention to serious or life-threatening risks”. While the severe side effect may not affect all or many of the patients on Invokana, due to the negative publicity and new stigma attached to the drug the usage rates will almost definitely fall as they have with other drugs who have been required to put the warning label on their drugs.