Medically reviewed by, Russell Braun RPH
Did it ever occur to you that medications you take may deplete important chemicals in your body such as vitamin D? Most people never even thought about a medication causing a low vitamin D level. Luckily for you, I am going to lay out the details on medications that deplete vitamin D, how to know for sure and what you can do about it.
According to the Centers for Disease Control (CDC) 48% of people in the U.S. have taken at least one medication in the last 30 days. Even worse, 24% of people have taken three or more prescriptions in that timeframe.
1. Why is vitamin D important?
It has been widely known for decades that vitamin D is vital to allow the absorption of calcium and phosphate. That is why it has always been recommended to get adequate levels to ensure proper bone growth in children. Adults also rely on vitamin D to help strengthen bones.
However, more and more research is showing some type of link to vitamin D and almost all other systems in the body. Vitamin D regulates calcium levels not only in the bones but blood levels too. This has been studied and found to play a role in many other health problems such as:
- Brain function
- Cardiovascular disease
- Diabetes type 1 & 2
- Hormone balance
- Immune response
- Liver function
- Multiple sclerosis
- Muscle function
- Nerve functions
In fact, a review of literature done in 2017 deemed that vitamin D deficiency is a pandemic affecting more than one billion people worldwide.
2. Do medications deplete vitamins?
Vitamin D is a hormone and impacts many systems in the body. What most people do not realize when they take medications is the effects they can have on levels of critical minerals and vitamins.
Certain medications may affect levels quickly, while others can lead to deficiency only with long term use. There are a few different ways that medications can deplete essential nutrients. These include:
- Blocking absorption
This means you can’t get the nutrient pulled into the bloodstream from the foods you eat.
- Increasing elimination
Increasing the amount of the drug that gets eliminated in the urine or feces.
- Inhibit the production of the nutrient
Prevention of the nutrient from being made into the active form in the body.
- Changing the metabolism
Blocking the way the drug is broken down so it can eventually be eliminated from the bloodstream.
Keep in mind that most medications will not lead to a deficiency. However, asking your doctor or pharmacist if there is a potential for it is critical. Interactions that lower levels of vitamin D are often overlooked by doctors. Don’t be afraid to ask!
3. What causes low vitamin D?
People get vitamin D from two sources. It is absorbed from foods in the diet and it can also be made in the skin when exposed to sunlight. Few foods contain high amounts of vitamin D. Additionally, people living north of the 37th parallel do not get enough direct UV rays of sunlight to produce adequate amounts of vitamin D. This is especially true in the winter.
Due to the lack of sun exposure and small amounts vitamin D in foods, deficiency is very common. According the the World Health Organization approximately 50% of the worlds population are deficient in vitamin D.
People who are especially at risk of deficiency include:
- People over age 65
- Obese people
- Those with dark skin
- Breastfed babies
- Those who live above 37 degrees latitude
4. What foods cause vitamin D deficiency?
Most processed foods that are consumed today are low in vitamin D. The biggest offenders are processed foods that contain preservatives and artificial flavors. If your diet is high in these foods and does not contain fruits, vegetables and fish then your more likely to have a vitamin D deficiency.
Most people do not eat enough of the foods that have vitamin D in them. Some examples of those foods include:
- Liver cod oil
- Egg yolks
- Orange juice
Even when people do eat foods rich in vitamin D they may not have enough servings per day.
5. How to know if you have a deficiency
Many people will not realize they have a vitamin D deficiency until it is too late. That is because they don’t realize that vitamin D may make them feel better and help lose weight. The symptom of a deficiency include weakened bones and bone loss. Unfortunately, by the time that shows up they are already at risk for ricketts in children or osteomalacia in adults.
How can you tell if your medications may be depleting your vitamin D before you suffer bone loss?
Getting a test to determine your vitamin D levels is important if you take one of the medications listed below. Tests measure the blood levels of 25 hydroxy-vitamin D, the active form of vitamin D in your blood.
The good news is getting a test is now easier than ever. You can get a test from your doctor, walk in to a lab or order a test online.
The table below describes the levels that are considered deficient all the way to ideal from the endocrine society guidelines. The levels are measured in nanograms per milliliter (ng/ml).
|What it means||Guideline blood level|
|Deficient||Below 20 ng/ml|
|Considered safe||< 100 ng/ml|
6. What medications affect vitamin D absorption?
Vitamin D is what is called a fat soluble vitamin. That means it is oil like and acts like oil in water and thus does not mix well with water. Therefore, if taken with another drug that is oil like, it will prevent vitamin D from being absorbed.
Mineral oil, that can be used as a laxative is one example of this type of medication.
Another class of medications that affect the absorption include those that bind to things in the intestine. Some medications used for cholesterol and weight loss work in this way.
7. What else prevents the absorption of vitamin D?
Vitamin D absorption is dependent on chemicals that are released by the stomach, pancrease, small intestine and bile from the liver. Anything that affects the health of your gut and these chemicals can decrease absorption.
In addition to keeping the gut healthy some diseases that affect the gut can seriously prevent the body from absorbing vitamin D. Examples of these diseases include:
|Crohn’s disease and IBS||Affect fat absorption due to inflammation.|
|Obesity||Often have other fat in the diet that vitamin D binds with and is excreted.|
|Gastric bypass surgery||Surgery affects the amount and release of normal chemicals that allow vitamin D to be absorbed.|
|Celiac disease||Due to changes in the intestines the body does not handle fat absorption properly.|
8. What medications cause low vitamin D?
Medications have the potential to lower vitamin D levels and cause deficiency. This fact is often overlooked by busy medical professionals. These interactions have also not been given much focus in medical journals.
As more and more people use prescription and over the counter medications all the time, vitamin D levels should receive more focus. Another reason to monitor 25-hydroxy vitamin D is that more commonly medications are being used over a prolonged period of time.
Drugs that affect the liver and kidneys
These organs are responsible for metabolizing (breaking down) and eliminating most drugs from the body. Therefore, medications can cause a delay in the normal processes done by the liver and kidneys. Vitamin D also requires the liver and kidneys to activate it from the inactive form D2 (ergocalciferol) to active D3 (cholecalciferol).
Other medications may speed up the processing by the liver and kidneys which can adversely affect vitamin D levels also.
Do antidepressants deplete vitamin D?
Research has shown a link between vitamin D blood levels and depression. This is more pronounced in obese patients than those of normal weight.
However, it has not been shown that medications used to treat depression specifically lower vitamin D levels. The only drugs used for depression that have been suspected of lowering vitamin D are tricyclic antidepressants. This seems to occur more in older people who may use these drugs for reasons other than depression, such as sleep aides.
More research is needed to determine if tricyclics deplete vitamin D levels. Common tricyclic antidepressants include:
9. Complete list of medications that deplete vitamin D
|Drug class||Drugs in the class||How it depletes vitamin D|
|Acid suppressing drugs||1. H2 blockers|
Ex: Pepcid, Axid, Tagamet, Zantac
2. Proton pump inhibitors
Ex: Nexium, Prilosec, Prevacid, Protonix
Ex: Tums, Rolaids Gaviscon
|Changes the acid level of stomach and vitamin D is not absorbed as well.|
|Antibiotics||Rifampin, Isoniazid||These antibiotics used to treat tuberculosis (TB) actually increase the metabolism of vitamin D. That increases how quickly it is eliminated from the body. |
|Antifungal drugs||Clotrimazole and Ketoconazole||These drugs can increase the metabolism of vitamin D, which causes it to be eliminated more quickly.|
|Anti-inflammatory drugs||Corticosteroids Ex: Prednisone, Decadron, Medrol, Kenalog|| |
Steroids cause an increased rate of the active form of vitamin D being converted to an inactive metabolite.
|Bone formation drugs||Bisphosphonates: Ex: Fosamax,||In order for these drugs to work properly, vitamin D should also be taken daily. If not, vitamin D levels will be lowered.|
|Cancer drugs||Cyclophosphamide, Docetaxel, Etoposide, Irinotecan, Tamoxifen, Vincristine||These drugs interact with an enzyme that is responsible for metabolizing vitamin D.|
|Cholesterol drugs||Cholestyramine, Colestipol||Block the absorption of vitamin D from the intestine.|
|Herbal drugs||St. John’s wort||This drug increases the metabolism of vitamin D and is excreted more rapidly.|
|HIV drugs||Atripla, Combivir, Intelence, Invirase, Retrovir, Reyataz, Stocrin, Sustiva, Trizivir||HIV drugs can reduce vitamin D levels through effects on metabolism and fat storage. Vitamin D is a fat soluble vitamin and changes in fat stores can affect the levels.|
|Laxatives||Mineral oil||Binds to vitamin D in the intestines and prevents it from being absorbed.|
|Seizure drugs||Carbamazepine, oxcarbazepine, phenobarbital, phenytoin||These drugs all increase the speed at which an enzyme that metabolizes vitamin D works. This leads to lower levels of vitamin D in the blood.|
|Weight loss drugs||Xenical, Alli, Orlistat||These drugs block the absorption of fats in the diet. Due to vitamin D being a fat soluble vitamin, this action by weight loss drugs keeps vitamin D from being absorbed.|
How can I raise my vitamin D level quickly?
If a vitamin D deficiency is found based on blood levels, there are four things you should try.
1. Talk to your doctor about medications and if they can be adjusted or switched to drugs that do not lower vitamin D levels.
2. Eat more servings of foods that contain Vitamin D.
3. Spend a small amount of time (15-20 minutes per day) in the sun without sunscreen on.
4. Try vitamin D supplementation. Typical recommended doses range from 400 IU to 4000 IU daily. You should talk with your doctor or pharmacist about the dosage that is best for you.
Doctors can also order prescription strength vitamin D, which is 50,000 IU typically taken once weekly. The other alternative is over the counter supplements. These need to be from manufacturers that follow the US Pharmacopeia standards. This ensures they are safe and the actual dosage on the label.
Both NatureMade and Kirkland Signature carry the USP seal of approval for vitamin D supplements.
Click here to get Dr. Jason Reed’s exclusive list of medication questions you MUST ask your doctor, for FREE!
Share your story
Have you taken a medication that lowers vitamin D levels? Also, please share if you have taken a vitamin D supplement. Chime in below with your comments and thoughts.