Pantothenic acid, also called vitamin B₅, is an antioxidant water-soluble vitamin needed to break down carbohydrates, proteins, and fats.

Pantothenic acid deficiency is very uncommon and more common with age. It is contained in whole grain cereals, legumes, eggs, meat, royal jelly and many other foods. Symptoms of deficiency are highly similar to other vitamin B deficiencies. They include allergies (e.g. stuffed or runny nose), adrenal insuffiency, Addison's disease and rheumatoid arthritis.

Pantothenic acid is an important tool in natural medicine, and replaces cortisone. It is also needed for proper and healthy growth of hair.