When it comes to cholesterol control, the first line of defense is always a healthy lifestyle and diet. But when that’s not enough, cholesterol medication can help to:
- Lower the heart-disease-causing bad cholesterol (low-density lipoprotein, LDL),
- Lower triglycerides, a type of fat in blood, which also increases the risk of heart problems, and
- Increase the heart-disease-resisting good cholesterol (high-density lipoprotein, HDL).
Statins are commonly used to fight cholesterol. Drugs in the statin family include:
- Altoprev and Mevacor (lovastatin),
- Lipitor (atorvastatin), and
- Zocor (simvastatin).
Statins lower cholesterol by directly inhibiting the production of cholesterol in the liver, which accounts for 70% of total cholesterol in our body.
The effectiveness and safety of statins and many other medications depends on the genetic makeup of the individual. Each year in Canada alone, ~200,000 adverse drug reactions occurs due to incorrect drug dosages.
The most common adverse drug reaction associated with statins is myopathy, which refers to any skeletal muscle weakness. For example, if you have difficulty rising from a chair, or raising your arms above your head.
Lovastatin, atorvastatin and simvastatin needs to be metabolized by the CYP3A4 enzyme in our liver for them to start lowering cholesterol.
Are statins safe?
Since many other medications are also metabolized by CYP3A4, you and your physician need to consider how these other medications can affect the way your body handles statins.
Case 1: If you take statin alone, then all of the CYP3A4 in your body is dedicated to metabolizing statin to fight cholesterol for you.
Case 2: If you take two medications: statin and X, and if X is also metabolized by CYP3A4, then some of the CYP3A4 is now used for metabolizing X. The amount of activated statin is reduced, and you may find your cholesterol levels increasing even though you are still taking the statin.
Case 3: If you take two medications, statin and Y, and if Y is a drug that inhibits the activity of CYP3A4, the statins you are taking will not be metabolized as quickly, which can lead to adverse side effects.
It all comes down to the availability of the CYP3A4 enzyme.
As we have discussed, CYP3A4 metabolizes statin. However, if the CYP3A4 enzyme in your body has a naturally lower metabolic activity, then even if you belong to Case 1 above, you might still run into problems.
Many studies have shown that individual variations in the gene that produce CYP3A4 will alter the effectiveness of statin therapy. Therefore, statin dosages needs to be adjusted depending on the your natural CYP3A4 activity for maximum safety and efficacy.
Dosage needs to be:
- Increased if your CYP3A4 activity is too low.
- Decreased if your CYP3A4 activity is higher than average.
How can you determine your natural CYP3A4 activity level?
The answer to this question is not as difficult as you would think. A painless genetic test by our PillCheckTMservice will let you know the status of your CYP3A4 enzyme. Your doctor will then be able to determine what is the safest and most effective dose of statin for you.
Since ~50% of all clinically used medication is processed by CYP3A4, information you acquire from this one single test can be applied to many other drugs, helping your doctors choose the correct dosage for you should you need other medications.
This is the first of a series of posts I will be writing on common medications prescribed today, so keep checking back on our blog for more updates, or follow us on Facebook and Twitter. If you have further questions, please feel free to call or email us.