Various combinations of drugs/vitamins/minerals may negate the effect of either the drugs or nutrients, while some of them may be potentially dangerous when taken in at the same time.
Alcohol weakens the body’s absorption of thiamin, riboflavin, niacinamide, pyrixodine, folic acid, calcium, iron, zinc, magnesium, selenium, and vitamin B12, C, A, and D.
ASPIRIN/NONSTEROIDAL ANTIINFLAMATION DRUGS
They affect absorption and activity of Vitamin C, folic acid, and iron.
Anticonvulsants such as phenytoin (Dilantin), phenobarbital, and primadone (mysoline) may obstruct the body’s use of folic acid (folacin) and vitamins D and K.
If used regularly, antacids, which contain aluminum, may interfere with the calcium status in the bones.
These drugs may interfere with the status of Vitamin A, B12, D, E, K, folic acid, calcium, and iron in the body.
Diuretics may cause potassium, magnesium, and zinc deficiencies.
Long-term use of products such as Metamucil can negatively affect the body’s absorption of zinc, iron, manganese, copper, beta-carotene, and vitamin B2 (riboflavin).
Use of some stool softener can negatively affect vitamins A and D in the body, while mineral oil may lead to vitamins A, D, E and K deficiencies.
Birth-control pills may interfere with pyridoxine (vitamin B6) and folic acid.
Cortisone-type steroids may cause breakdown of protein in bone and may lead to osteoporosis-like disorders. Calcium supplementation is needed if a person uses steroids.
Sunscreens with sun protective factor (SPF) of eight and higher may block formation of Vitamin D in the skin. If a person uses sunscreen with high SPF, dietary intake and supplementation of Vitamin D is needed.
Source: Sheldon Saul Hendler, MD, The Doctors’ Vitamin and Mineral Encyclopedia