Testing of Vit. D

Testing for Vitamin D

There is a simple blood test — 25 hydroxyvitamin D test — your doctor can order to check your level of vitamin D. Some doctors, though, don't give the test unless you ask for it.

Vitamin D and Other Drugs

Steroid medications can interfere with metabolism of vitamin D. If you take steroids, you should discuss vitamin D with your doctor. The same is true for the weight loss drug orlistat, some cholesterol-lowering drugs, and seizure drugs such as phenobarbitol. Cholesterol-lowering statins, on the other hand, will raise vitamin D levels.

How Much Is Too Much?

There is an upper limit to how much vitamin D you can safely take. Current Institute of Medicine recommendations for adults say that a daily intake of up to 2,000 IU of vitamin D is safe. Some experts say that limit is far too low. However, you should not take more vitamin D than that unless you're told to do so by your doctor. The upper limit for infants is lower. Talk with your doctor about how much vitamin D is safe for your child.