Camphor is a powder that originally came from the bark and wood of the camphor tree.
Today, most camphor is synthetic. It's in some products that are applied to the skin, including FDA-approved treatments. It's a common ingredient in remedies applied to the skin for cough and skin irritation.
Chlorella may make it harder for warfarin and other blood-thinning drugs to work.
Some chlorella supplements may contain iodine, so people with thyroid conditions may want to avoid taking chlorella.
Always tell your doctor about any supplements you are taking, including natural ones and those bought without a prescription. That way, your doctor can check on any potential side effects or interactions with any medications.