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Background: It is well established that an excessive intake of retinol (vitamin A) is toxic; however, it has been > 25 y since the last extensive treatise of case reports on this subject. Objective: The objectives were to identify and evaluate all individual cases of retinol toxicity published in the scientific literature that assessed the thresholds and symptoms induced by high intakes of retinol and to compare the toxicity of different physical forms of retinol preparations. Design: We performed a meta-analysis of case reports on toxicity claimed to be induced by intakes of excessive amounts of dietary retinol (ie, retinol and retinyl esters in foods or supplements). Using free text and MESH (medical subheading) strategies in PubMed, we identified 248 articles in the scientific literature. From these initial articles we identified other relevant citations. The final database consisted of 259 cases in which individual data on dose, sex, age, time of exposure, and symptoms are reported. Results: Chronic hypervitaminosis A is induced after daily doses of 2 mg retinol/kg in oil-based preparations for many months or years. In contrast, doses as low as 0.2 mg retinol * [kg.sup.-1] * [d.sup.-1] in water-miscible, emulsified, and solid preparations for only a few weeks caused chronic hypervitaminosis A. Thus, water-miscible, emulsified, and solid preparations of retinol are [approximately equal to] 10 times as toxic as are oil-based retinol preparations. The safe upper single dose of retinol in oil or liver seems to be [approximately equal to] 4-6 mg/kg body wt. These thresholds do not vary considerably with age. Conclusions: The results of the present study indicate that the physical form of retinol supplements is a major determinant of toxicity. The use of water-miscible, emulsified, and solid preparations of retinol should therefore be carefully considered before being used in supplements and fortifications. KEY WORDS Vitamin A toxicity, hypervitaminosis A, fortification, retinol, retinyl esters, water-miscible retinol, emulsified retinol, supplements

The temporal association of symptoms consistent with ephedrine toxicity after ingestion of ephedrine-containing dietary supplements is heavily relied upon to confirm exposure. Few reports in the literature attempt to associate toxicity with serum levels of these drags. We report a case of ephedrine-induced cardiac ischemia confirmed by a plasma level. A 22-year-old woman ingesting an ephedrine- and caffeine-containing product for 2 days presented with multiple symptoms, including palpitations, nausea, tremulousness, abdominal pain, and vomiting. The initial electrocardiogram (ECG) revealed a normal sinus rhythm with 1 mm of ST segment depression in leads V3 and V4, along with inverted T waves in leads V1-V4. Her symptoms and ST segment depression resolved over several hours with medical management. The amplitude of her T wave inversions notably diminished with therapy; however, they did not completely resolve. Troponins at presentation and the following morning were negative, and an echocardiogram showed only trace tricuspid regurgitation. A serum ephedrine level, drawn approximately 6 to 7 hr after ingestion, was 150 ng/mL. She was discharged from the hospital after being instructed to avoid ephedrine-containing products. Key Words: Ephedrine; Cardiac; Ischemia., INTRODUCTION Ma huang, an herbal source of ephedrine, is a common ingredient of many dietary supplements sold as stimulants, weight reduction aids, or athletic performance enhancers. It is estimated that [...]

Introduction. Hepatic toxicity from manufactured herbal remedies that contain kava lactones has been reported in Europe, North America, and Australia. There is no evidence for serious liver damage in kava-using populations in Pacific Island societies or in Indigenous Australians who have used aqueous kava extracts. This article presents evidence that liver function changes in users of aqueous kava extracts appear to be reversible. Data from one Arnhem Land community [Northern Territory (NT), Australia] with 340 indigenous people older than 15 years of age in 2000 are used. Methods. This study was a cross-sectional study with 98 participants, 36 of whom had never used kava. Among 62 kava users, 23 had discontinued kava at least 1 year before the study. Continuing users had not used kava for 1 to 2 months (n = 10) or 1 to 2 weeks previously (n = 15). Some (n = 14) had used kava within the previous 24 hr. Liver function tests were compared across these groups, taking into account differences due to age, sex, alcohol, and other substance use. Results. The average quantity of kava powder consumed was 118 g/week, and median duration of use was 12 years (range, 1-18 years). Kava usage levels were less than one-half of those found in previous studies. More recent kava use was independently associated with higher levels of liver enzymes gamma-glutamyl transferase (GGT) (p < 0.001) and alkaline phosphatase (ALP) (p < 0.001), but not with alanine aminotransferase or bilirubin, which were not elevated. In those who were not heavy alcohol users, only those who used kava within the previous 24 hr showed GGT levels higher than nonusers (p < 0.001), whereas higher ALP levels occurred only in those who last used kava 1 to 2 weeks (p = 0.015) and 24 hr previously (p = 0.005). Discussion. Liver function changes in users of aqueous kava extracts at these moderate levels of consumption appear to be reversible and begin to return to baseline after 1 to 2 weeks abstinence from kava. No evidence for irreversible liver damage has been found. Key Words: Hepatic toxicity; Kava; Aqueous extracts; Indigenous Australian., INTRODUCTION Since the late 1990s, several countries have reported serious irreversible liver damage in people using herbal products that contain ethanol or acetone extracts of kava lactones (1-3). Consequently, manufactured [...]

You want to lose some weight. You hear about this stuff at the drugstore that melts pounds away. What's the harm. Ellen Ruppel Shell investigates the current crop of diet […]

M&F weighs the pros and cons of a next-generation muscle building supplement. (Special Report) HAILED AS THE TOP BODYBUILDING SUPPLEMENT, creatine is arguably the best legal performance enhancing agent on [...]

Background: Iron deficiency anemia (IDA) is common in pregnant women, but previous trials aimed at preventing IDA used high-dose iron supplements that are known to cause gastrointestinal side effects. Objective: The objective was to assess the effect on maternal IDA and iron deficiency (ID, without anemia) of supplementing pregnant women with a low dosage (20 mg/d) of iron. Effects on iron status were assessed at the time of delivery and at 6 mo postpartum. Gastrointestinal side effects were assessed at 24 and 36 wk of gestation. Design: This was a randomized, double-blind, placebo-controlled trial of a 20-mg daily iron supplement (ferrous sulfate) given from 20 wk of gestation until delivery. Results: A total of 430 women were enrolled, and 386 (89.7%) completed the follow-up to 6 mo postpartum. At delivery, fewer women from the iron-supplemented group than from the placebo group had IDA [6/198, or 3%, compared with 20/185, or 11%; relative risk (RR): 0.28; 95% CI: 0.12, 0.68; P < 0.005], and fewer women from the iron-supplemented group had ID (65/186, or 35%, compared with 102/176, or 58%; RR: 0.60; 95% CI: 0.48, 0.76; P < 0.001). There was no significant difference in gastrointestinal side effects between groups. At 6 mo postpartum, fewer women from the iron-supplemented group had ID (31/190, or 16%, compared with 51/177, or 29%; RR: 0.57; 95% CI: 0.38, 0.84; P < 0.005). The rate of IDA between the groups did not differ significantly at 6 mo postpartum. Conclusion: Supplementing the diet of women with 20 mg Fe/d from week 20 of pregnancy until delivery is an effective strategy for preventing IDA and ID without side effects. KEY WORDS Iron, pregnancy, iron deficiency, randomized controlled trial

Dietary supplements are used by more than one-half of the adult US population. In contrast to pharmaceuticals, dietary supplements may be sold in the United States with little regulation other than listing of ingredients and the potential health benefits. By contrast, herbal products in Germany are carefully regulated by the same standards as drugs, and efforts are under way to standardize their regulation in the entire European Union. Most herbal users do not inform their physicians that they are taking these supplements, and most physicians do not inquire. Although some herbal products have clinically proven benefits, it is increasingly apparent that many contain potentially toxic substances, particularly in relation to interactions with drugs. Hence, it is essential that practicing physicians develop a working knowledge of herbals--specifically, about claims for their usage and potential or proven efficacies and toxicities--and that they incorporate such knowledge into the evaluation and management of their patients. By contrast, functional foods--integral components of the diet that are understood to contribute added health benefits--are the subject of intense and widespread research in food and nutritional science. Examples include many polyphenolic substances, carotenoids, soy isoflavones, fish oils, and components of nuts that possess antioxidant and other properties that decrease the risk of vascular diseases and cancer. Practicing physicians are advised to stay abreast of these emerging findings in order to best advise their patients on the value of health-promoting diets in disease prevention. KEY WORDS Dietary supplements, herbal products, functional foods, challenges to medical practitioners

Background. Herbal preparations are available widely and regarded generally by the public as harmless remedies for a variety of medical ailments. We report a case of acute hepatitis associated with the use of kava kava, derived from the root of the pepper plant, Piper methysticum. It is used in the United States as an antianxiety and sedative agent. Case report. A previously healthy 14-year-old female was admitted to the hospital with hepatic failure. Initial therapy, including plasmapheresis, was unsuccessful and she deteriorated. She ultimately required a liver transplant and now remains well. The liver biopsy showed hepatocellular necrosis consistent with chemical hepatitis. A work-up for alternative causes of liver failure was negative. The patient gave a history of taking a kava kava-containing product for four months. The use of kava kava and liver failure, is supported by kava kava use, a negative work-up for alternative causes of liver failure, and histological changes in the liver. Conclusions. Health care professionals need to be aware of the possibility of kava kava-induced hepatotoxicity. The toxicity of these alternative remedies emphasizes the importance of surveillance programs and quality control in the manufacture of these products. Clinicians must remain aware of the toxic potential of herbal products and always inquire about their intake in cases of unexplained liver injury., INTRODUCTION Herbal medicines have become a popular alternative form of therapy to traditional western medicine (1). Kava kava, for example has become increasingly popular in the United States and Europe [...]

Background: The herbal mixture PC-SPES, used to manage advanced prostate cancer, has proven thrombogenic and highly estrogenic in clinical trials. However, attempts to identify the active compounds in PC-SPES have yielded incongruous results. Moreover, warfarin was identified in the serum of a patient taking PC-SPES who experienced a bleeding disorder. To determine the active components in PC-SPES potentially responsible for these effects, we analyzed PC-SPES lots manufactured from 1996 through mid-2001. Methods: Antineoplastic activity of PC-SPES and its individual component extracts was determined by colony-forming assays with several prostate cancer cell lines, and estrogenicity was determined by analyzing expression of an estrogen-responsive reporter gene in breast cancer cells. High-pressure liquid chromatography was used to isolate, identify, and quantify components of PC-SPES. Components were also identified by proton nuclear magnetic resonance, gas chromatography/mass spectrometry, and mass spectra analysis. Results: PC-SPES lots manufactured from 1996 through mid-1999 contained the synthetic compounds indomethacin (range = 1.07-13.19 mg/g) and diethylstilbestrol (range = 107.28-159.27 [micro] g/g) and were two to six times more antineoplastic and up to 50 times more estrogenic than lots manufactured after the spring of 1999. In lots manufactured after mid-1999, gradual declines in the concentrations of indomethacin (from 1.56 to 0.70 mg/g), diethylstilbestrol (from 46.36 to 0.00 [micro] g/g), and total phytosterols (from 0.586 to 0.085 mg/g) were observed. Warfarin was identified for the first time in lots manufactured after July 1998 (range = 341-560 [micro] g/g). In the August 2001 lot, increases were found in concentrations of the natural products licochalcone A (from 27.6 to 289.2 [micro] g/g) and baicalin (from 12.5 to 38.8 mg/g). Conclusions: The phytochemical composition of PC-SPES varied by lot, and chemical analyses detected various amounts of the synthetic drugs diethylstilbestrol, indomethacin, and warfarin and several natural products. To qualify for clinical pharmacologic exploration, nutritional supplements including herbal mixtures should meet standards of quality control under the Good Manufacturing Practice system, and the manufacturers of such supplements should provide reliable analytical quality assurance.

Background: Personal health care practices that may include the use of dietary supplements are common in the United States. Products marketed as dietary supplements are diverse and may include botanicals, vitamins, and/or minerals. Chaparral (Larrea tridentata) is a botanical dietary supplement made from a desert shrub and used for its antioxidant properties. Several reports of chaparral-associated hepatitis have been published since 1990, but a complete picture of the clinical presentation is still unclear. Materials and Methods: We reviewed the 18 case reports of adverse events associated with the ingestion of chaparral reported to the Food and Drug Administration between 1922 and 1994. These reports were from health care professionals, state health departments, and individual consumers. Results: Of 18 reports of illnesses associated with the ingestion of chaparral, there was evidence of hepatotoxicity in 13 cases. Clinical presentation, characterized as jaundice with a marked increase in serum liver chemistry values, occurred 3 to 52 weeks after the ingestion of chaparral, and it resolved 1 to 17 weeks after most individuals stopped their intake of chaparral. The predominant pattern of liver injury was characterized as toxic or drug-induced cholestatic hepatitis; in 4 individuals, there was progression to cirrhosis; and in 2 individuals, there was acute fulminant liver failure that required liver transplants. Conclusions: These data indicate that the use of chaparral may be associated with acute to chronic irreversible liver damage with fulminant hepatic failure, and they underscore the potential for certain dietary supplement ingredients to cause toxic effects on the liver. Health professionals should be encouraged to inquire routinely about the use of dietary supplements and other products, to be alert to potential adverse effects that may be associated with these products, and, finally, to report any serious adverse events associated with these products through the MEDWatch Program of the Food and Drug Administration.

The effect of calcium on iron absorption was determined in 126 healthy adults, ages 19 to 58. Calcium chloride (CC) was added to dinner rolls prior to and after baking. When 40 milligrams (mg) of CC was added to the roll dough prior to baking, iron absorption from the accompanying meal was reduced by 40 percent. When 300 to 600 mg of CC was added to the dough, iron absorption was reduced by 75 to 80 percent. Addition of CC to roll dough was found to increase the phytate content of the rolls (because phytate breakdown was inhibited). Since phytate may reduce iron absorption, the effect of adding CC to rolls after baking was also determined. When 40 mg of CC was added to the rolls after baking, iron absorption was not inhibited. However, at higher doses of CC (300 mg), iron absorption was reduced by 60 percent. When 165 mg of calcium was administered in the form of milk or cheese, iron absorption was reduced by 50 to 60 percent. This dose of calcium also decreased heme-iron absorption, indicating that calcium may inhibit the transfer of iron across intestinal cells and into the bloodstream. It is possible that calcium competes with iron for binding to specific transporters that carry nutrients across cell membranes, thus allowing them to be absorbed. Further studies regarding the effect of calcium on iron absorption are needed to gain a better understanding of the nutritional, physiological and clinical implications of these findings. (Consumer Summary produced by Reliance Medical Information, Inc.)

* Four patients fulfilling the case definition for gosinophiliamyalgia syndrome are described, including one whose disease began in 1986. Each displayed a variety of symptoms: one suffered principally from myalgia and recovered spontaneously on discontinuation of L-tryptophan therapy; one exhibited progressive sclerodermiform skin changes, neuropathy, and myopathy; a third had prominent neuromuscular disease and sclerodermiform skin changes; and the fourth experienced profound weight loss, an axonal polyneuropathy, and perivascular lymphoid infiltrates simulating a lymphoma. Evidence of T-cell activation was present in peripheral blood and affected tissues during the clinically active progressive phase of disease. Among other manifestations pleural effusion, cutaneous vasculitis, joint contractures, and bloody diarrhea were observed. A history of L-tryptophan ingestion should be sought in patients with myalgia, fatigue, or the above outlined symptoms. (Arch Intern Med. 1990;150:2178-2186)

Photosensitivity, an abnormal skin reaction to light, is a rare adverse event associated with herbal medicine use. Case reports in the literature most commonly implicate St. John's wort. In this report, we describe the case of a 32-year-old woman who suffered a phototoxic reaction after taking a dietary supplement containing ginseng, goldenseal, bee pollen, and other ingredients. On presentation, she had a pruritic, erythematous rash, localized to the sun-exposed surfaces of her neck and extremities. She had no significant past medical history and was not taking any other medications. The skin rash slowly resolved after discontinuation of the supplement and with treatment including subcutaneous and topical corticosteroids. Although the individual ingredients in this dietary supplement have not been associated with cases of photosensitivity, it is possible that the combination of ingredients may have interacted to cause this toxic reaction. Therefore, we recommend caution in the combining of multiple herbs and supplements into new formulations. Key Words: Herbal; Skin; Adverse reaction., INTRODUCTION Drug-induced photosensitivity is an abnormal cutaneous reaction to light caused by either systemic or topical administration of a drug (1). Photosensitivity may be phototoxic, related to potentiation of the [...]

* The eosinophilia-myalgia syndrome is a newly described disorder related to the ingestion of L-tryptophan-containing products. Its presentation may mimic other disorders characterized by eosinophilia and muscle pain and/or weakness, but can be differentiated by certain characteristic laboratory and pathologic findings. We report two such cases, describe their features, and review similar syndromes. (Arch Intern Med. 1990;150:2175-2177)

The ingestion of fish oil and decreased mortality due to coronary artery disease has been reported. This led to extensive use of commercially developed preparations of refined fish oils as dietary supplements to reduce hyperlipidemia, excessive fat content of the blood. However, there are potentially harmful side effects to the use of these supplements, such as problems relating to the function of platelets, clotting factors in the blood. Research concerning bleeding abnormalities may reduce the use of these supplements. This study was conducted to determine the benefit of dietary fish oil supplementation on a group of eleven adolescent patients with hyperlipoproteinemia type II. The results indicate that there was no significant effect on plasma lipid levels from the use of the dietary fish oil supplement. An unexpected finding was a high incidence of bleeding problems. There were nine episodes of epistaxis, or nose bleeds, in 8 of the ll patients during the time they were receiving the supplement. There was no history of nose bleed in the pre- or post-treatment period. Three of the adolescent patients had abnormal bleeding times. It is concluded that the dose of fish oil necessary to reduce blood lipid levels may be associated with an extremely high risk of bleeding problems in adolescents. (Consumer Summary produced by Reliance Medical Information, Inc.)

Byline: Yeager, Selene too much of a good thing It's not just fries and fat you have to fret about in the home of the free and the big. We [...]

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Dietary supplements containing ephedra can pose severe health risks and even cause death, according to a study conducted for the FDA by scientists at the University of California, San Francisco. [...]

Background: Colloidal silver protein (CSP) has been used as a popular nutritional supplement for many years. CSP has been promoted to boost immune response and is claimed to be effective against many forms of infections. Although silver-containing drugs are no longer available for OTC sale, CSP is available in health food stores as well as over the Internet. We report a case of argyria due to chronic use of CSP. Case Report: A 35-year-old woman presented with bluish-gray discoloration of the skin and nail beds. The discoloration was more pronounced in sun exposed areas. The patient is a housewife with no hobbies involving chemicals or excessive outdoor activities. She has no underlying diseases and is on no medications except for a nutritional supplement called 'mild colloidal silver protein' containing 25 mcg/tsp of elemental silver. The patient had been taking this product orally, in accordance with the labeled instructions, instructions, daily for one year. Laboratory studies, including liver and renal functions, are all normal. Heavy metal screens of urine were all negative, including silver, lead, mercury, and arsenic. Skin biopsy was not done. Based on the patient's history of CPS use, the total cumulative dose of silver before the onset of skin discoloration was 66 mg. Discussion: Chronic exposure to silver-containing products has been known to cause silver deposition in various organ systems including skin, liver, kidney, gastrointestinal tract, brain and cornea. Such deposition results in chronic skin discoloration, which is effectively irreversible and untreatable. Although argyria is thought to be a relatively benign condition, silver deposition has been shown to be associated with central nervous system dysfunction in animals. In humans, there is one case report of seizures in a patient who had been taking a silver-containing product for 40 years and had a very high serum silver level. Although argyria has been reported with chronic ingestion of colloidal silver products, the estimated accumulated amount of elemental silver consumed in our patient is low compared to previously reported cases. Conclusion: We report this case to illustrate the potential for permanent, disfiguring complications of a commonly used nutritional supplement product., Chomchai S, Kim SY. California Poison Control System, San, Francisco. University of California at San Francisco, San Francisco, [...]

Laser Clot Busters Although pharmacologic lysis of intraluminal clots represents a major advance in stroke care, it carries certain limitations. Specifically, the treatment window is quite narrow, and hemorrhage is [...]

SAN FRANCISCO -- Ginger, garlic, and feverfew all have significant anticoagulant activity and need to be used with caution by the elderly, David J. Kroll, Ph.D., warned at the annual [...]

Background: Dietary supplements are exempted from pre-marketing research and post-marketing surveillance for safety. Case Series: Calls involving dietary supplements were prospectively collected by 11 poison centers in 1998. Over half are entered into a Microsoft Access database. Symptomatic cases where the ingested dietary supplements were judged to have at least 50% probability of causing the symptoms were reviewed. Symptomatic calls per total number of calls by age in years were: [is less than] 1:11/47; 1-5:31/390; 6-11:5/27; 12-17:32/79; 18-34: 123/399; 35-59:94/200; [is greater than or equal to] 60: 14/50; unknown age 27/273 (total 1465). The predominant symptoms in infants were vomiting and drowsiness. 1 infant developed seizures, and another, hepatotoxicity. Four cases occurred with breast-feeding. Calls concerning elderly included a case of hepatotoxicity, as well as of coma and hypertension/tachycardia. GI symptoms (97) were most commonly reported for all ages followed by hypersensitivity (53) reactions (5 with respiratory symptoms), and CNS agitation (47) or drowsiness (39). Three deaths (2 with Ma Huang, one Pao d'arco) and severe symptoms included seizure (7, one Wormwood), coma (4), anticholinergic toxicity (5), chest pain (12), conduction abnormalities (12), hepatotoxicity (7, one Jin Bu Huan) and coagulopathy (4). Multi-ingredient products ([is greater than] 3 ingredients/product) predominated the high symptom group (97) followed by, and sometimes including, thermogenic products or 'fuels' (50, usually containing Ma Huang), St. John's Wort (17), cultural herbal remedies (12), Kava (11), Ginkgo (10), Ginseng (9), and Melaleuca oil (6). Conclusion: These pilot data question the safety of dietary supplements, with special focus on extremes of age and symptoms., Palmer M, Haller C, McKinney P, Tschirgi A, Klein-Schwartz W, Smolinske S, Everson G, Nelson L, Woolf A, Bartlett D, Dahl B, Dodd-Butera T. Dietary Supplement Poison Center Study [...]

Background: Ephedrine has previously been described as a causative factor of vasculitis but myocarditis has not yet been associated with either ephedrine or its plant derivative ephedra. Case Report: A 39-year-old African American male with hypertension presented to Rush Presbyterian St. Luke's Medical Center with a 1-month history of progressive dyspnea on exertion, orthopnea, and dependent edema. He was taking Ma Huang (Herbalife) 1-3 tablets twice daily for 3 months along with other vitamin supplements, pravastatin, and furosemide. Physical examination revealed a male in mild respiratory distress. The lung fields had rales at both bases without audible wheezes. Internal jugular venous pulsations were 5 cm above the sternal notch. Medical therapy with intravenous furosemide and oral enalapril was initiated upon admission. Cardiac catheterization with coronary angiography revealed normal coronary arteries, a dilated left ventricle, moderate pulmonary hypertension, and a pulmonary capillary wedge pressure of 34 mm Hg. The patient had right ventricular biopsy performed demonstrating mild myocyte hypertrophy and an infiltrate consisting predominantly of lymphocytes with eosinophils present in significantly increased numbers. Treatment for myocarditis was initiated with azothioprine 200 mg daily and prednisone 60 mg per day with a tapering course over 6 months. Anticoagulation with warfarin and diuretics was initiated and angiotensin-converting enzyme inhibition was continued. Hydralazine was added later. One month into therapy, an echocardiogram demonstrated improved left ventricular function with only mild global hypokinesis. A repeat right ventricular biopsy 2 months after the first admission showed no evidence of myocarditis. At 6 months, left ventricular ejection fraction was normal (EFN 50%) and the patient asymptomatic. Conclusion: Ephedra (Ma Huang) is the suspected cause of hypersensitivity myocarditis in this patient due to the temporal course of disease and its propensity to induce vasculitis., INTRODUCTION Ephedra (Ma Huang) is a popular herbal product originating from China which contains from 0.5% to 2.5% sympathomimetic alkaloid (primarily ephedrine and pseudoephedrine). While cardiotoxicity is usually due to [...]

The Food and Drug Administration has issued a warning about a new group of dietary supplements, marketed as sleep aids, aphrodisiacs, and muscle builders, that have caused at least 3 [...]