The B-complex vitamins contain eight water-soluble vitamins that differ in name, structure and function. As a group, the B-complex vitamins function as coenzymes in various metabolic tasks. They help the body convert food to energy and metabolize fats and protein. The B vitamins are necessary for healthy skin, hair, eyes and liver and help the nervous system function properly. Vitamins can be obtained through the diet and from supplements and medications. Niacin, or vitamin B-3, in medication form can cause severe muscle pain.
Niacin
Niacin, also known as vitamin B-3 and nicotinic acid, plays a role in helping the body produce sex- and stress-related hormones. It also functions to improve circulation and lower cholesterol levels. In medication form, niacin belongs to a group called statins. Statins are prescribed to help lower cholesterol and reduce the risk of heart attack and stroke.
Muscle Pain
The Mayo Clinic states that the most common side effect of statin medication is muscle pain. The pain can be soreness, tiredness or general weakening of the muscle. The scale of pain can range from mild to severe and can make normal activities difficult. On rare occasions, statins have caused rhabdomyolosis, a condition of life-threatening muscle damage. Rhabdomyolosis can cause severe muscle pain, liver damage, kidney failure and death. Again, this is a rare condition and usually occurs when statins, not necessarily niacin, are taken in conjunction with other medications.
RDA and Food Sources
The recommended dietary allowance, or RDA, for niacin varies with age, gender and health condition. The RDA for healthy men and women over the age of 19 is 16 and 14 mg per day, respectively. Food sources of niacin include beets, brewer's yeast, beef liver, beef kidney, fish, salmon, swordfish, tuna, sunflower seeds and peanuts. Likewise, foods that contain tryptophan, an amino acid that can be converted into niacin, include red meat, poultry, eggs and dairy products.
Side Effects and Considerations
Due to possible side effects, talk to your health-care provider before taking a niacin supplement. Possible side effects of niacin include diarrhea, dizziness, headaches, heartburn, increased cough, indigestion or upset stomach, nausea, temporary reddening of skin, itching, tingling, flushing and vomiting. More severe side effects include severe allergic reaction, black or bloody stool, changes in vision, decreased urine production, darkened urine, fainting, rapid and irregular heartbeat, flu-like symptoms, increased sweating, loss of appetite, tenderness, swelling and weakness, severe and persistent diarrhea, nausea and vomiting, shortness of breath, yellowing of the skin and muscle pain ranging from mild to severe. Even mild muscle pain can lead to a more serious condition. Seek medical attention immediately if any of these side effects occur.
