Metformin: Common Drug-Nutrient Interactions

Active Hydrogen Adrenal Extracts Alanine Alpha-Linolenic Acid Alpha-Lipoic Acid AMP Amylase Inhibitors Arginine Bee Pollen Beta Carotene Beta-glucan Betaine Beta-Sitosterol Biotin Borage Oil Boron Bovine Cartilage Bovine Colostrum Brewer's Yeast Bromelain Calcium Capsaicin Carnitine Carnosine Chitosan Chloride Chlorophyll Chondroitin Chromium CLA Cobalt Coenzyme Q10 Copper Creatine Cysteine DHA DHEA DMAE EGCG Evening Primrose Oil 5-HTP Fiber (Insoluble) Fiber (Soluble) Fish Oil Flavonoids Fluoride Folate Fumaric Acid GABA Gamma-Linolenic Acid Glucomannan Glucosamine Glutamic Acid Glutamine Glutathione Glycine Grape Seed Extract Histidine HMB Hydroxycitric Acid Indole Inosine Inositol Iodine Ipriflavone Iron Isoleucine Lactase Lecithin Leucine Lipase Lutein Lycopene Lysine Magnesium Malic Acid Manganese Mannose Melatonin Methionine Methoxyisoflavone Molybdenum MSM N-Acetyl Cysteine NADH Naringin Niacin Octacosanol Oligosaccharides Olive Leaf Extract Ornithine Oryzanol PABA Pancreatic Enzymes Pantothenic Acid Phenylalanine Phosphatidylserine Phosphorus Phytic Acid Policosanol Potassium Pregnenolone Probiotics Propolis Psyllium Pyridoxine Pyruvate Quercetin Resveratrol Retinol Riboflavin Ribose Royal Jelly SAMe Selenium Shark Cartilage Silicon Sodium Spirulina Spleen Extracts St. John's Wort Strontium Sulforaphane Sulfur Taurine Thiamine Tocopherol Tea Tree Oil Tyrosine Usnic Acid Valine Vanadium Vinpocetine Vitamin A Vitamin B1 Vitamin B2 Vitamin B3 Vitamin B5 Vitamin B6 Vitamin B9 Vitamin B12 Vitamin C Vitamin D Vitamin H Vitamin K Whey Protein Xylitol Zinc

Abalone Shell (shi jue ming)
Abutilon Seed (dong kui zi)
Acanthopanax Bark (wu jia pi)
Achyranthes (niu xi)
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Corydalis (yan hu suo)
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Cranberry (vaccinium macrocarpon)
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Croton Seed (ba dou)
Curculigo (xian mao)
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Cuttlefish Bone (hai piao xiao)
Cymbopogon (xiang mao)
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Dichroa Root (chang shan)
Dittany Bark (bai xian pi)
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Dragon Bone (long gu)
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Epimedium (yin yang huo)
Erythrina Bark (hai tong pi)
Eucalyptus (eucalyptus globulus)
Eucommia Bark (du zhong)
Eupatorium (pei lan)
Euphorbia Root (gan sui or kan sui)
Euryale Seed (qian shi)
Evodia (wu zhu yu)
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Fenugreek (hu lu ba)
Fermented Soybeans (dan dou chi)
Flaxseed (ya ma zi)
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Honey (feng mi)
Honeysuckle Flower (jin yin hua)
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Huperzia (qian ceng ta)
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Ilex (mao dong qing)
Imperata (bai mao gen)
Indigo (qing dai)
Inula (xuan fu hua)
Isatis Leaf (da qing ye)
Isatis Root (ban lan gen)
Java Brucea (ya dan zi)
Jujube (da zao)
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Kadsura Stem (hai feng teng)
Katsumadai Seed (cao dou kou)
Kelp (kun bu)
Knotweed (bian xu)
Knoxia root (hong da ji)
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Lapis (meng shi)
Leech (shui zhi)
Leechee Nut (li zhi he)
Leonorus (yi mu cao)
Lepidium Seed (ting li zi)
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Lily Bulb (bai he)
Limonite (yu liang shi)
Lindera (wu yao)
Litsea (bi cheng qie)
Lobelia (ban bian lian)
Longan (long yan hua [rou])
Lophatherum (dan zhu ye)
Loquat Leaf (pi pa ye)
Lotus Leaf (he ye)
Lotus Node (ou jie)
Lotus Seed (lian zi)
Lotus Stamen (lian xu)
Luffa (si gua luo)
Lycium Bark (di gu pi)
Lycium Fruit (gou qi zi)
Lygodium (hai jin sha)
Lysimachia (jin qian cao)
Magnetite (ci shi)
Magnolia Bark (hou po)
Magnolia Flower (xin yi hua)
Maitake (grifola frondosa)
Marigold (c. officinalis)
Massa Fermentata (shen qu)
Milk Thistle (silybum marianum)
Millettia (ji xue teng)
Mint (bo he)
Mirabilite (mang xiao)
Morinda Root (ba ji tian)
Mugwort Leaf (ai ye)
Mulberry Bark (sang bai pi)
Mulberry Leaf (sang ye)
Mulberry Twig (sang zhi)
Mullein (jia yan ye)
Musk (she xiang)
Myrrh (mo yao)
Notoginseng (san qi)
Notopterygium (qiang huo)
Nutmeg (rou dou kou)
Oldenlandia (bai hua she she cao)
Omphalia (lei wan)
Onion (yang cong)
Ophicalcite (hua rui shi)
Ophiopogon (mai dong)
Oroxylum Seed (mu hu die)
Oryza (gu ya)
Oyster Shell (mu li)
Passion Flower (passiflora incarnata)
Patrinia (bai jiang cao)
Pau D'Arco (tabebuia avellanedae)
Peach Seed (tao ren)
Pearl (zhen zhu [mu])
Perilla Leaf (su ye)
Perilla Seed (su zi)
Perilla Stem (su geng)
Persimmon (shi di)
Pharbitis Seed (qian niu zi)
Phaseolus (chi xiao dou)
Phellodendron (huang bai)
Phragmites (lu gen)
Picrorhiza (hu huang lian)
Pinellia (ban xia)
Pine Knots (song jie)
Pipe Fish (hai long)
Plantain Seed (che qian zi)
Platycodon (jie geng)
Polygala (yuan zhi)
Polygonatum (huang jing)
Polyporus (zhu ling)
Poppy Capsule (ying su qiao)
Poria (fu ling)
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Prinsepia Seed (rui ren/zi)
Prunella (xia ku cao)
Prunus Seed (yu li ren)
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Pyrite (zi ran tong)
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Quisqualis (shi jun zi)
Radish (lai fu zi)
Realgar (xiong huang)
Red Atractylodes (cang zhu)
Red Clover (trifolium pratense)
Red Ochre (dai zhe shi)
Red Peony (chi shao)
Red Sage Root (dan shen)
Rehmannia (shu di huang)
Reishi (ling zhi)
Rhubarb (da huang)
Rice Paper Pith (tong cao)
Rose (mei gui hua)
Rosemary (mi die xiang)
Safflower (hong hua)
Saffron (fan hong hua)
Sandalwood (tan xiang)
Sanguisorba Root (di yu)
Sappan Wood (su mu)
Sargent Gloryvine (hong teng)
Saw Palmetto (ju zong lu)
Schefflera (qi ye lian)
Schisandra (wu wei zi)
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Scirpus (san leng)
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Sea Cucumber (hai shen)
Sea Horse (hai ma)
Seaweed (hai zao)
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Shiitake (hua gu)
Siegesbeckia (xi xian cao)
Siler Root (fang feng)
Slippery Elm (ulmus fulva)
Smilax (tu fu ling)
Smithsonite (lu gan shi)
Sophora Flower (huai hua mi)
Sophora Root (ku shen)
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Stellaria (yin chai hu)
Stemona (bai bu)
Stephania (fang ji [han])
Sweet Annie (qing hao)
Teasel Root (xu duan)
Tiger Bone (hu gu)
Torreya Seed (fei zi)
Tortoise Plastron (gui ban)
Tremella (bai mu er)
Trichosanthes Fruit (gua lou)
Trichosanthes Root (tian hua fen)
Trichosanthes Seed (gua lou ren)
Tsaoko Fruit (cao guo)
Turmeric (jiang huang)
Turtle Shell (bie jia)
Tussilago (kuan dong hua)
Urtica (xun ma)
Uva ursi (arctostaphylos uva-ursi)
Vaccaria Seed (wang bu lui xing)
Valerian (jie cao)
Veratrum (li lu)
Viola (zi hua di ding)
Vitex (man jing zi)
Walnut (hu tao ren)
Watermelon (xi gua)
White Atractylodes (bai zhu)
White Mustard Seed (bai jie ze)
White Peony (bai shao)
Wild Asparagus (tian men dong)
Windmill Palm (zong lu pi/tan)
Xanthium (cang er zi)
Zedoary (e zhu)

If any of your patients are taking this drug for blood sugar control, you need to know how certain supplements can impact its effectiveness.

By Todd Mexico, DC and Brandon Blood, DC

The topic of drug-nutrient interactions is becoming increasingly popular, even reaching national television. "The Dr. Oz Show" recently spotlighted this subject.¹ It also needs to become increasingly popular in terms of our patient care. Chiropractors, nutritionists, pharmacists, medical doctors and others all have the responsibility to protect patients from negative drug-nutrient interactions, as well as provide better patient care by recommending nutritional supplementation that could enhance patient health and well-being, particularly for those taking medication.

As we continue our educational series on the importance of understanding drug-nutrient interactions, let's dissect metformin, a drug commonly used to control blood sugar levels in patients with type 2 diabetes.² According to Diabetes.org, 7.8 percent of Americans have diabetes, with 1.6 million new cases diagnosed every year.³ In 2006, diabetes was listed as the seventh leading cause of death in the United States.

When it comes to potential drug-nutrient interactions, especially relative to metformin, one most understand pharmacodynamic interactions between drugs and nutrients that may be additive or synergistic in nature. A different example to further explain this is coumadin and fish oil. Both are blood thinners and when consumed together, have a synergistic outcome. There are several supplements that have positive effects on decreasing blood-sugar levels. Although this is desirable, it can potentially lead to hypoglycemia, an equally undesirable outcome if not managed correctly. For the purpose of this article, all synergistic interactions will be considered negative for this reason.

Potential Positive Supplement Interactions With Metformin

Vitamin B₁₂: Consuming vitamin B₁₂ while on metformin may combat B₁₂ malabsorption/deficiency, as metformin is known to decrease B₁₂ levels.^4-6
Omega-3 fatty acids: Consuming omega 3 EFAs may help reduce hypertriglyceridemia and heart disease associated with diabetes.^7-10
CoQ₁₀: Consuming CoQ₁₀ may improve blood sugar control as well as combat reduced CoQ₁₀ production, as metformin is known to decrease CoQ₁₀ production.^11-13

Potential Negative Supplement Interactions With Metformin

Chromium: May help improve blood sugar control,^14-16 which, when consumed with metformin, may ultimately lead to low blood sugar levels. Should be medically co-managed.
Cocoa (Theobroma cacao): May decrease the effect of metformin, causing potentially undesirable effects in patients dependent on the drug for blood sugar control.¹⁷
Fenugreek (Trigonella sp.): As with chromium, may improve blood sugar control, which, when consumed with metformin, may ultimately lead to low blood sugar levels. Should be medically co-managed.^18,19

The findings above are not inclusive of the potential drug-nutrient interactions with metformin; they are just a sample of the information that has been researched. It is important for chiropractors to analyze all medications and nutritional supplements their patients are taking for possible interactions. It is perhaps equally important to document these results in a manner that exhibits due diligence from a medical-legal standpoint. By understanding this research and applying your nutritional knowledge in practice, you will likely also see an increase in patient confidence in the care you provide.

References

"Mixing Medicines Is Risky Business." www.doctoroz.com/videos/mixing-medicines-risky-business
Becker ML, et al. Genetic variation in the multidrug and toxic extrusion 1 transporter protein influences the glucose-lowering effect of Metformin in patients with diabetes. Diabetes, March 2009.
American Diabetes Association. Diabetes statistics. www.diabetes.org/diabetes-basics/diabetes-statistics
Adams JF, et al. Malabsorption of vitamin B12 and intrinsic factor secretion during biguanide therapy. Diabetologia, 1983;24(1):16-8.
Ting RZ, Szeto CC, Chan MH, et al. Risk factors of vitamin B12 deficiency in patients receiving metformin. Arch Intern Med, 2006;166:1975-9.
Pflipsen, et. al. The prevalence of vitamin B12 deficiency in patients with type 2 diabetes: a cross-sectional study. J Am Board Fam Med, 2009;22:528-34.
Schectman G, Kaul S, Kissebah AH. Effect of fish oil concentrate on lipoprotein composition in NIDDM. Diabetes, 1988;37:1567-73.
Sheehan JP, Wei IW, Ulchaker M, Tserng KY. Effect of high fiber intake in fish oil-treated patients with non-insulin-dependent diabetes mellitus. Am J Clin Nutr, 1997;66:1183-7.
Friedberg CE, Janssen MJ, Heine RJ, Grobbee DE. Fish oil and glycemic control in diabetes: a meta-analysis. Diabetes Care, 1998;21:494-500.
Toft I, Bonaa KH, Ingebretsen OC, et al. Effects of n-3 polyunsaturated fatty acids on glucose homeostasis and blood pressure in essential hypertension: a randomized, controlled trial. Ann Intern Med, 1995;123:911-8.
Kishi T, et al. Bioenergetics in clinical medicine. XI. Studies on CoQ and diabetes mellitus. J Med, 1976;7(3-4):307-21.
Hodgson JM, Watts GF, Playford DA, et al. Coenzyme Q(10) improves blood pressure and glycaemic control: a controlled trial in subjects with type 2 diabetes. Eur J Clin Nutr, 2002;56:1137-42.
Singh RB, Niaz MA, Rastogi SS, et al. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. J Human Hypertens, 1999;13:203-8.
Anderson RA, Cheng N, Bryden NA, et al. Elevated intakes of supplemental chromium improve glucose and insulin variables in individuals with type 2 diabetes. Diabetes, 1997;46:1786-91.
Mertz W. Interaction of chromium with insulin: a progress report. Nutr Rev, 1998;56:174-7.
Porter DJ, Raymond LW, Anastasio GD. Chromium: friend or foe. Arch Fam Med, 1999;8:386-90.
Boullata J. Natural health product interactions with medication. Nut Clin Pract, 2005.
Sharma RD, Raghuram TC, Sudhakar Rao N. Effect of fenugreek seeds on blood glucose and serum lipids in type 1 diabetes. Eur J Clin Nutr, 1990;44:301-6.
Sharma RD, Sarkar A, Hazara DK, et al. Use of fenugreek seed powder in the management of non-insulin dependent diabetes mellitus. Nutr Res, 1996;16:1131-9.

Drs. Todd Mexico and Brandon Blood, who are both 2006 graduates of Palmer College of Chiropractic Florida, are the president and vice president, respectively, of eMedFx.com. Dr. Mexico practices in Baldwinville, Mass., while Dr. Blood maintains a practice in Canton, Ohio.