Do Drug Interactions cause Statin Side Effects?
A vast majority of the U.S population suffers from high cholesterol. Unlike most other diseases, high cholesterol frequently presents with no symptoms and can be considered a silent killer. Today, over 70 million adult Americans have high cholesterol, yet only 1 in 3 actually have the condition under control.
What are statins?
Statins are the first line of defense against high cholesterol and have been around for decades. The first statin, lovastatin, was approved in the United States over 30 years ago on September 1st, 1987. Since then, statin use has increased steadily over the years, and today they are one of the most widely prescribed medications in the U.S. In fact, nearly 1 in 4 adults over 40 years of age are taking a statin.
The most commonly used statin in the U.S right now is atorvastatin, which was approved in 1996. While the majority of statins currently available are several decades old, there are newer statin options available. Pitavastatin was introduced to the U.S. in 2009 and is the most recently approved type of statin. Pitavastatin is different than most statins—let’s discuss how!
What are drug interactions?
Drug interactions don’t typically refer to drugs directly interacting with other drugs. Instead, drugs, supplements, or foods can interact with each other indirectly by stimulating or inhibiting different enzymatic processes in our bodies. Under certain circumstances, this can lead to unintended interactions.
Statins, like atorvastatin, are metabolized in our liver by an enzyme called cytochrome P450 (CYP450). This enzyme helps to break down the statin and remove it from our body after it has done its job of lowering cholesterol. Unfortunately, 70-80% of medications are also processed by the same family of enzymes. When these enzyme pathways become too busy it can lead to drug interactions.
Newer statins like pitavastatin are different than most statins and are not processed by these same enzymes. Therefore, there is less potential for certain interactions.
Do drug interactions cause statin side effects?
The short answer is yes, they can.
In most cases, your doctor or pharmacist should be able to predict when these interactions will occur and often can modify the medications you are taking to reduce the chance of a bad interaction from occurring. For example, statin-related side effects like muscle pain (called myalgia), while relatively rare, typically increase with the statin dosage. Therefore, if you are taking 40 mg of atorvastatin and are experiencing muscle aches or pain, your doctor may first try to reduce your dose to 20 mg to see if that will help.
Now how does this relate to drug interactions? As discussed earlier, 70-80% of medications are metabolized by the CYP450 family of enzymes. In addition, some supplements and certain foods can also interact with these enzymes. A classic example of the effects of a drug interaction occurs when someone takes atorvastatin in combination with grapefruit juice. Grapefruit juice inhibits the CYP450 family of enzymes. When this enzyme is blocked, this can result in an increased amount of atorvastatin in your blood, which can greatly increase the risk of muscle pains and aches.
That’s why it’s so important for your healthcare provider to know about all the over-the-counter products, supplements, and prescription medications you are currently taking.
Newer Statins bypass this common enzyme pathway and have reduced potential for certain drug interactions
There is good news. There is a newer statin available now called pitavastatin. Pitavastatin (available under the brand name of Zypitamag® at Marley Drug) bypasses this enzyme family and is instead mainly processed by a less busy enzyme family called UDP-glucuronosyltransferases, or UGTs. This pathway results in a reduced potential for certain interactions with other medications. It’s like comparing a crowded freeway with a dedicated express lane.
If you ever experience side effects from your statin, be sure to talk to your healthcare team right away. There are lots of statin options available. If you have had issues with your statin in the past that doesn’t mean you will have the same issue with every single statin. Not all patients are the same. Not all statins are the same.