Sunday, December 2, 2007

Over-the-Counter Supplement Overdose

“Vitamins are America's favorite supplements; you may be among the 40% who took at least one within the past month. All told, we spend $1.7 billion a year on those pills and capsules” (Smith, 2000, p. 89). Patients are unaware that vitamin and herbal interactions, with prescribed medication, commonly occur and can have effects similar to drug-drug interactions. Patients are taking over-the-counter vitamin and herbal supplements to live a healthier life style, but are actually harming themselves, by decreasing the effectiveness of prescribed medications, overdosing on the supplement, and increasing their risk for other health problems.
First, patients are harming themselves by taking over-the-counter vitamin and herbal supplements, by decreasing the effectiveness of prescribed medications. Common vitamin and herbals taken by the general population are: Fat soluble vitamins A, D, E and K which need dietary fat to be absorbed (Nix, 2004, p. 89-97). A few examples of water soluble vitamins are: Vitamin C (Ascorbic Acid), B1(Thiamine), B2 (Riboflavin), B3 (Niacin) etc. Water soluble vitamins are absorbed easily and directly into blood circulation from the gastrointestinal tract and do not require a carrier for transport into blood circulation (Nix, 2004, p. 97-122). Common herbal supplements include: St. John’s Wart is used for mild depression; Ginseng is used to improve appetite, memory, and sleep pattern; Ginger can be used for decreased nausea and vomiting related to motion sickness, pregnancy, chemotherapy, and surgery; Garlic is used for high blood pressure, high cholesterol, and prevention of cardiovascular disease; Ginkgo is used for improved peripheral circulation and sexual dysfunction; and Kava used for anxiety, stress, restlessness, insomnia, mild muscle ache and pain, menstrual cramps, and premenstrual syndrome (Delgin, 2005, p.1190-1213). One example of supplements interacting with medications adversely is Warfarin, also known as Coumadin. Warfarin is commonly used for prevention of thromboembolism, pulmonary embolism, atrial fibrillation with embolization, and myocardial infarction. Supplements that decrease the effect of Warfarin, placing the patient at risk for thromboembolism, are St. John’s Wart and Ginseng. Supplements that increase the effects of Warfarin, by thinning the blood and placing the patient at risk for bleeding, are Garlic, Ginger, and Ginkgo (Delgin, 2005, p.1097).
In addition to decreasing the effectiveness of prescribed medications, vitamin and herbal supplements are harmful, because patients are overdosing on the supplements. Patients believe that water soluble vitamins are excreted in your urine, making it impossible to overdose on vitamins. Unfortunately, some water soluble vitamins have Upper Intake Levels. According to the article “Does your supplement provide a nutrient overdose? New recommendations on vitamin A and other nutrients reveal how much is too much.” featured in Tufts University Health & Nutrition Letter in April of 2001, the Upper Intake Level (UL) is the highest amount of a vitamin or mineral that you could take daily without suffering adverse effects. For example, the UL for vitamin C (ascorbic acid) is 2000mg/day and the UL of vitamin B3 (niacin) is 35mg/day. See chart from Tufts University Health & Nutrition Letter for UL on other vitamin and minerals on page 9 of this report. Fat-soluble vitamins can be stored in large amounts in the liver. Patients who are not aware of this will take daily doses of fat-soluble vitamins increasing their risk for overdosing. Another term for vitamin and supplement overdosing is megadosing. Megadosing on vitamins can cause a rebound effect, leading to a deficiency known as “artificial induced deficiency”. A rebound effect is a response in which a sudden withdrawal of stimuli is followed by a physiological effect either positively or negatively affecting the body. The example given in Williams’ Basic Nutrition & Diet Therapy Twelfth Edition, published in 2004, was infants born with scurvy due to mothers taking megadoses of vitamin C during pregnancy. After delivery, the baby was no longer receiving high volumes of vitamin C and in turn had a rebound effect of being deficient in vitamin C. (Nix, 2004, p.145-146).
Not only do vitamin and herbal supplements decrease the effectiveness of prescribed medications, and place the patient at risk for accidental overdose, but they increase the patient’s risk for other health problems. Patients taking an excess amount of vitamin C may experience osmotic diarrhea and gastrointestinal upset (Nix, 2004, p.100). Megadosing on vitamin B6 can lead to lack of muscular coordination and nerve damage (Nix, 2004, p.108). Elevated amounts of fat-soluble vitamins can potentially lead to liver and brain damage. Overdosing on vitamin A can lead to joint pain, thickening of long bones, loss of hair, jaundice, portal hypertension, and ascites (Nix, 2004, p.91). Ingesting an exorbitant amount of vitamin D may lead to calcification of soft tissues, such as kidneys and lungs, as well as fragile bones (Nix, 2004, p.92). Surplus amounts of vitamin E can interfere with bleeding (Smith, 2000, p.89). Profuse doses of herbal Kava can lead to liver damage (Delgin, 2005, p. 1206). The list of risks from overdosing on supplements is vast.
Evidence indicates that vitamin and herbal supplementation are causing harmful effects on patient outcomes, by decreasing the effectiveness of prescribed medications, overdosing on the supplement, and increasing their risk for other health problems. Patients should be informed that vitamins are like drugs, and can be harmful if taken in excess or with certain medications. They should be instructed to read labels carefully, and identify the need versus supplemental use. Most importantly, it is imperative for patients to report all over-the-counter vitamin and herbal supplements with their prescribed medications when asked. Ultimately, food is the best source of nutrients.
hart from Tufts University Health & Nutrition Letter for UL
Legend for Chart:
A - Nutrient
B - Goal for intake[*]
C - Upper intake level

A B C

Vitamin A Women: 2,333 IU 10,000 IU
Men: 3,000 IU

Vitamin K Women: 90 micrograms Not established[A]
Men: 120 micrograms

Boron Not established 20 milligrams

Chromium Women: 20-25 micrograms Not established[A]
Men: 30-35 micrograms

Copper Women: 900 micrograms 10,000 micrograms
Men: 900 micrograms

Iodine Women: 150 micrograms 1,100 micrograms
Men: 150 micrograms

Iron Women (pre-menopausal): 45 milligrams
18 milligrams

Women (post-menopausal):
8 milligrams

Men: 8 milligrams

Manganese Women: 1.8 milligrams 11 milligrams
Men: 2.3 milligrams

Molybdenum Women: 45 micrograms 2,000 micrograms
Men: 45 micrograms

Nickel Not established 1 milligram

Silicon Not established Not established[A]

Vanadium Not established 1.8 milligrams

Zinc Women: 8 milligrams 40 milligrams
Men: 11 milligrams

[*] Values given are for adults ages 19 and up unless
otherwise noted.

[A] There's not enough scientific evidence yet to set a
UL for vitamin K, chromium, or silicon.
Work Cited
Deglin, Judith H., Vallerand, April H., 2005. Davis’s Drug Guide for Nurses Ninth Edition. Philidelphia, PA. F.A. Davis Co.
Does your supplement provide a nutrient overdose? New recommendations on vitamin A and other nutrients reveal how much is too much. Tufts University Health & Nutrition Letter, 2001 April, 19(2), 4-5. Retrieved July29, 2007. from Academic Search Premier. CINAHL Database. http://search.ebscohost.com/login.aspx?direct=true&db=cin20&AN=2003098206&site=ehost-live
Nix, Stacy. (2004, October). Williams’ Basic Nutrition & Diet Therapy Twelth Edition. p.86-154. Salt Lake City, UT. Mosby
Smith, Ian K. (2000, April 24). Personal time: your health. Vitamin Overdose: New Government Recommendations for C and E suggest that maybe mother was right after all. Time.155 (16), 89-89. Retrieved July 29, 2007, from Academic Search Premier. CINAHL Database. http://search.ebscohost.com/login.aspx?direct=true&db=cin20&AN=2000052763&site=ehost-live
Willett, W.C., Skerrett, P. (2004, January 19). A Simple Cure for Confusion. Newsweek, 143(3), 55-56, Retrieved July 29, 2007, from Academic Search Premier. CINAHL Database. http://search.ebscohost.com/login.aspx?direct=true&db=cin20&AN=2004075007&site=ehost-live
Intervention 1: Patients should be informed that vitamins are like drugs, and can be harmful if taken in excess or with certain medications.
Disadvantage 1: Patients often take over-the-counter herbals believing there are no interactions because they do not see a warning on the label. In the article “Herbal Medicine” featured in Kansas Nurse in May 2007, Kathleen Wold, EdD, ANP, BC states, “In 1994 Congress passed the Dietary Supplement Health and Education act (DSHEA) to protect sonsumers. Products are allowed to make health claims such as ‘promotes immune systems health’ but they do not have to have proof of efficacy.” Contraindications with prescribed drugs are not required on the warning label for herbal supplements. This, erroneously, leads patients to believe that the herbal supplement they are taking will not have an interaction with the medication they are prescribed, and is the reasoning behind why patients do not relinquish this information to their healthcare professional. They believe that since they are buying it over-the-counter and there are no warnings for contraindications on the label, there is no reason to report this on their medication list.
Citation
Wold, K. “Herbal Medicine”. Kansas Nurse. May 2007. 82(5): 6-8 (28 ref). Retrieved Oct 31, 2007. Academic Search Premier. CINAHL Database. URL: www.cinahl.com/cgi- bin/refsvc?jid=230&accno=2009600319
Disadvantage 2: The popularity of herbal supplementation has risen. “There are many herbal products on the market that are heavily advertised and are popular with consumers (Wold, 2007, p. 6).” Due to the constant barrage of advertisements regarding the benefits of vitamin and herbal supplements, there is a rising number of patients that are trying to self prescribe. Patients are trying to be healthier and so in the efforts of doing something proactive for their own health, they are overlooking the possible pitfalls of medication interactions. Patients are often on several different supplements making their medications lists as long as 20 or more different types of oral supplements, making it very difficult for health providers to cross reference each and every supplement.
Wold, K. “Herbal Medicine”. Kansas Nurse. May 2007. 82(5): 6-8 (28 ref). Retrieved Oct 31, 2007. Academic Search Premier. CINAHL Database. URL: www.cinahl.com/cgi- bin/refsvc?jid=230&accno=2009600319
Intervention 2: They should be instructed to read labels carefully, and identify the need versus supplemental use.
Disadvantage 1: Even if the patients are reading the labels, vitamins and herbal supplements are not federally regulated. The information listed on the actual bottle may not reflect the actual amount that the tablet or capsule really contains. In the article “Multi-ple Failures”, featured in Environmental Nutrition in April 2007, “a study performed by ConsumerLab.com revealed “11 out of 21 multivitamins tested included significantly more or less of a nutrient than the label claimed, an inability of the multivitamin to disintegrate within 30 minutes which is the amount of time need for the adequate absorption by the body, and contamination with lead.” Without federal regulations and reliable standards, consumers can not trust the labels on the vitamins and herbal supplements they are purchasing. This makes it difficult for patients to make informed decisions regarding the vitamin and herbal supplements they are taking. Patients can do more research on websites that offer more detailed information about the safety & efficacy of nutrition supplementation at the following websites: Quackwatch www.quackwatch.com, National Institute of Health Office of Dietary Supplements http://dietary-supplements.info.nih.gov, Supplement Watch www.supplementwatch.com, and National Center for Complementary and Alternative Medicine http://nccam.nih.gov.
Citation
Multi-ple Failures, Environmental Nutrition. April 2007. 30(4): 3. Retrieved Oct 30, 2007. from Academic Search Premier. CINAHL Database. URL: www.cinahl.com/cgi- bin/refsvc?jid=2777&accno=2009609651
Disadvantage 2: In addition to the lack for federal regulation of dosage amounts on the labels of vitamin and herbal supplements, the FDA recommended daily intake values may be misleading. In the article “Multivitamin/mineral supplements: Needed insurance?” featured in Harvard Women’s Health Watch in January 2007, the writer states, “The FDA’s current recommended daily intake of vitamin A - 5,000 International Units (IU) - is probably overgenerous, and it doesn’t distinguish between the two forms of vitamin A, retinol (listed as vitamin A acetate or palmitate) and beta carotene.” Patients may not be aware that there are different forms or names that vitamins are identified as. This misconception can lead to megadosing on vitamins & herbal supplements that can become harmful or toxic. Patient safety is at risk.
Citation
Multivitamin/mineral supplements: Needed insurance? Harvard Women’s Health Watch. January 2007. 14(5): 6-7. Retrieved Oct 30, 2007. from Academic Search Premier. CINAHL

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