We all know a friend or relative on statins. Statins entered the pharmaceutical market in force about 15 years ago.
They form a class of “lipid-lowering” medication, which means it lowers the amount of bad cholesterol in your body, preventing future heart disease in both people with risk factors and those without.
Although considered a “mainstream” medication that has been used safely for quite a long while, there are certain facts about statins that I want to share with you!
1. Why can’t I have grapefruit when I’m on statins?
If you’re on statins yourself, you must have remembered the pharmacist telling you to avoid grapefruit or its juice. Why of all fruits, grapefruit?
Here’s the explanation:
- Statins are processed in the liver by a group of enzymes known as CYP3A4.
- Grapefruit and its juice contains substances which inhibit these enzymes.
- By doing so, statins cannot be processed and broken down as quickly, so it accumulates.
- A higher than normal level of statins in the body makes side effects more likely.
These side effects include:
- Muscle breakdown
- Liver damage
- Muscle and joint pain
- Neurological side effects
However, there are some types of statins which have less interaction with grapefruit. So if you’re a huge grapefruit fan and can’t go without it, speak to your healthcare provider about alternatives.
Pravastatin for one, is not broken down by that particular group of enzymes in the liver, hence it is less susceptible to interactions along that pathway.
2. Why must I take my statin at night?
Look at the white label that comes with your medication. Chances are, your statin label will say to take it at night, before bedtime.
If so, I do hope you’ve been following instructions and taking it at night! Taking it in the morning is NOT THE SAME!
Studies of human physiology have shown that cholesterol (which is what statins are supposed to reduce) is made in the body when dietary intake is lowest.
For most of us, this is at night when we are asleep and not eating. Hence, taking statins before bedtime allows it to work best!
Unconvinced, but on a statin that screams “take at night”? Check this study out!
3. Are all statins the same?
Statins are a big family. Using “statin” as almost a surname, we have:
- Simvastatin (probably the most commonly prescribed statin)
- Atorvastatin (AKA Lipitor®)
- Rosuvastatin (AKA Crestor®)
This list is not exhaustive of all the statins, but these are the few we commonly see in Singapore practice. So comes the question, are all statins the same?
Theoretically, yes. All statins work in the same way. They prevent a certain enzyme called HMG-CoA reductase from working, thereby blocking the liver from making cholesterol.
However, there are some not-so-subtle differences between them.
For example, Atorvastatin, Rosuvastatin and Pravastatin stay in the body longer (due to relatively longer half-lives), and can be taken during the day time. This allows for more flexibility in dosing schedules, compared to a short half-life statin like Simvastatin.
In terms of speed of effect, Lovastatin also tends to work faster than Simvastatin.
4. Which statins are subsidised in Singapore?
The issue of cost always comes to mind. Simvastatin, Atorvastatin, Lovastatin and Pravastatin are on the Standard Drug List for subsidised prices. Singaporeans can purchase these drugs more cheaply at public healthcare institutions.
(Also read: Are you paying too much for your medication?)
Other statins more commonly prescribed by private healthcare providers may be charged at a premium.
5. Statins are not a Get-Out-Of-Jail-Free card against unhealthy eating habits
Just because statins can help you “produce less cholesterol” doesn’t mean you should neglect a healthy lifestyle.
Statins work best when combined with exercise, eating in moderation and making good food choices!
6. Always let new healthcare providers know about your statin
Most common statins are processed by liver enzymes (remember our CYP3A4?) However, these same enzymes also process other medication you may be taking.
Dangerous interactions can happen when certain medications are taken with statins. These include:
- Gemfibrozil – another cholesterol-lowering medication (especially so with simvastatin)
- Antifungals (eg. ketoconazole, fluconazole)
- Antibiotics (eg. clarithromycin)
- HIV medication
Each time you visit a new healthcare provider, it’s always important that you let him know if you are taking a statin (as well as other medication).
If you take multiple medications daily, do bring along a medication list in your wallet!
Sarah is a fully registered pharmacist with the Singapore Pharmacy Council. She’s currently working towards completing a further degree in public health. Things that excite her include a good book, a good cup of coffee and being able to help people use medicines safely. Sometimes she takes and shares photos @munlinggg.