August 26th, 2015|
What patients need to know about injuries related to the Type II diabetes drug Invokana.
What is Invokana?
Invokana belongs to a new class of Type II diabetes drugs called sodium-glucose cotransporter 2 (SGLT-2) inhibitors.
Invokana is produced by Jassen Pharmaceuticals, a division of Johnson & Johnson. The drug was approved by the Food and Drug Administration (FDA) in March 2013, and was the first drug in its class (SGLT-2 inhibitors) to be approved for use in the United States
What are SGLT-2 inhibitors? How do they work?
Normally, the body – specifically the pancreas – produces insulin to process sugar, or glucose, that enters the body while eating. Insulin is the hormone that allows glucose to be absorbed from the bloodstream.
In individuals with Type II diabetes this response no longer works properly, and they develop insulin resistance, meaning they fail to sufficiently absorb glucose from the blood. Eventually, demand for insulin outstrips the pancreas’ ability to keep up, and blood sugar can rise to dangerous levels.
In contrast to many other diabetes medications that work to increase insulin levels, SGLT-2 inhibitors, like Invokana, work by stopping the reabsorption of glucose into the blood in the kidneys. These drugs inhibit SGLT-2, a special protein that reabsorbs glucose in the kidneys. Rather than being reabsorbed, glucose is instead secreted from the kidneys, and passes out of the body during urination.
What health complications are associated with Invokana and other SGLT-2 inhibitors?
In May 2015, the FDA issued a warning that “the Type II diabetes medicines canagliflozin, dapagliflozin, and empagliflozin may lead to [diabetic] ketoacidosis.” The FDA warning noted 20 cases of diabetic ketoacidosis (DKA) linked to SGLT-2 inhibitor use from March 2013 to June 6, 2014. Since then, the FDA has continued to receive reports of DKA linked to these drugs, but has issued no recalls.
Ketoacidosis generally describes acidification of the blood. The below list of diabetes medications (with active ingredient[s] in parentheses) all may cause DKA:
- Invokana (canagliflozin)
- Invokamet (canagliflozin and metformin)
- Farxiga (dapagliflozin)
- Xigduo XR (dapagliflozin and metformin extended-release)
- Jardiance (empagliflozin)
- Glyxambi (empagliflozin and linagliptin)
DKA occurs when the body cannot use glucose as a fuel source due to low or non-existent levels of insulin. The body breaks down fat for energy instead, which produces ketones and makes the blood more acidic. High levels of ketones in the blood are toxic.
DKA is a serious condition requiring medical attention. Symptoms include:
- Difficulty breathing
- Unusual fatigue or sleepiness
- Frequent urination or thirst lasting for a day or more
- Flushed face
- Fruity-smelling breath
- Aching muscles or muscle stiffness
- Vomitting and nausea
- Stomach pain
The FDA warning strongly recommends individuals prescribed a SGLT-2 inhibitor to pay close attention for signs of DKA, and to immediately seek medical attention if they develop the above symptioms. The FDA also advises that patients do not stop taking their medication without consulting their doctor first.
A doctor can make a diagnosis of DKA through blood and/or urine testing.
In addition to ketoacidosis, SGLT-2 inhibitors may also be linked to increased risk of kidney damage and heart attack.