Thread: Diet pills?
View Single Post
Old 07-30-2002, 02:55 PM   #13 (permalink)
Formulated Solutions
 
Join Date: Oct 8 2001
Posts: 150
Rep Power: 23 Formulated Solutions is on a distinguished road
Ephedra: From the Natural Medicines Comprehensive Database

Also Known As:
Cao Mahuang, Desert Herb, Ephedrae herba, Ephedra sinensis, Herbal Ecstasy, Joint Fir, Ma Huang, Ma-Huang, Mahuang, Mahuanggen (ma huang root), Muzei Mahuang, Popotillo, Sea Grape, Teamster's Tea, Yellow Astringent, Yellow Horse, Zhong Mahuang.
CAUTION: See separate listing for Mormon Tea.
Scientific Names:
Ephedra distachya; Ephedra equisetina; Ephedra gerardiana; Ephedra intermedia; Ephedra shennungiana; Ephedra sinica; and other Ephedra species.
Family: Ephedraceae.
People Use This For:
Orally, ephedra is used for weight loss and obesity and to enhance athletic performance. It is also used for allergies and allergic rhinitis; nasal congestion; and respiratory tract conditions such as bronchospasm, asthma, and bronchitis. It is also used orally for colds, flu, fever, chills, headache, edema, anhydrosis, joint and bone pain, and as a diuretic for edema.
Safety:
POSSIBLY UNSAFE ...when used orally. There is concern that use of ephedra can cause severe life-threatening or disabling adverse effects in some people. Several case reports have linked ephedra use to hypertension, myocardial infarction, seizure, stroke, and other significant adverse effects. Some suggest that ephedra is only harmful when used inappropriately in excessive doses. However, in several cases significant adverse events occurred with short-term use of relatively low doses ranging from 20-60 mg of ephedra alkaloids (2729,6486). Based on case reports, it is not possible to determine the incidence of these serious adverse effects or to determine who is at the greatest risk. However, people with existing conditions such as cardiovascular disease or those using ephedra products in combination with other stimulants such as caffeine, might be at increased risk. Until more is known, advise patients to avoid ephedra products. Tell them that any potential benefits of ephedra do not outweigh the potential risks.
LIKELY UNSAFE ...when used orally in high doses or long-term. Prolonged use or use of high doses can increase the risk of serious adverse effects (2729). Chronic use can also cause rapid development of tolerance and dependence (2,12).
CHILDREN: LIKELY UNSAFE ...when used orally. Children can be more susceptible to the adverse effects of ephedra (2,12).
PREGNANCY: LIKELY UNSAFE ...when used orally. Ephedra can stimulate uterine contraction (12); contraindicated.
LACTATION: Insufficient reliable information available; avoid using.
Effectiveness:
POSSIBLY EFFECTIVE …when used orally, short-term for obesity. There is preliminary evidence that a specific combination product containing ephedra, guarana, and 17 other vitamins, minerals, and supplements (Metabolife-356) might help reduce weight by approximately 2.7 kg over 8 weeks when used with a low-fat diet and exercise (3719). However, there are serious concerns about the safety of this product since it combines significant amounts of the stimulants ephedra and caffeine (See Adverse Reactions). Tell patients to avoid using this product. ...when taken orally for short-term treatment of respiratory conditions, including asthma, bronchitis, and bronchospasm (2,3,6,7). However, doses recommended for these indications often exceed the safe limit (2729) and better treatment alternatives are available.
There is insufficient reliable information available about the effectiveness of ephedra for its other uses.
Mechanism of Action:
The applicable part of ephedra is primarily the dried, young branch. Less commonly, the root or whole plant is used (11,13,18). Ephedra in dietary supplements is usually either a formulation of powdered stems and aerial portions or a dried extract (6488). Dried extracts contain more ephedra alkaloids per unit weight of material, due to the extraction process. The principle alkaloid constituents are ephedrine, pseudoephedrine, and sometimes small amounts of phenylpropanolamine. Ephedrine is absorbed faster if it is consumed as the powdered extract. However, onset of action and extent of absorption does not differ greatly between the powdered extract and the powdered herb (6008,6009). Some sources claim ephedra is safer than pure ephedrine and pseudoephedrine because ephedrine from ephedra is absorbed more slowly. However, pharmacokinetic studies have found no differences in the pharmacokinetics of ephedrine from ephedra versus the purified form (6488). Ephedrine and pseudoephedrine are both non-selective alpha- and beta-receptor agonists. The ephedrine and pseudoephedrine constituents can directly and indirectly stimulate the sympathetic nervous system (2,3,6,7,9). They can increase systolic and diastolic blood pressure (3,6,11,18) and heart rate (3,6,11), cause peripheral vasoconstriction, bronchodilation (3,6,7,11), and central nervous system stimulation (2,3,7,11). Ephedra alkaloids have been linked to myocarditis and myocardial infarction. This has been attributed to coronary artery vasoconstriction and possibly vasospasm caused by ephedra. Ephedra might also cause cardiac arrhythmia due to adrenergic effects that shorten the cardiac refractory period, causing re-entrant arrhythmias. Cerebral hemorrhage associated with ephedra has been attributed primarily to hypertensive effects and possibly due to cerebral vasculitis, which has been reported with other adrenergic drugs. Ischemic stroke has been attributed to ephedra’s vasoconstrictive effects on cerebral vasculature and possibly platelet aggregation effects due to adrenergic stimulation (6486). Ephedrine also seems to have antitussive (2,7), bacteriostatic (2), and anti-inflammatory (6,11) activity. Ephedrine can have diuretic effects, but can also exacerbate urinary retention (512). Ephedra can have either hypoglycemic or hyperglycemic effects. It can also stimulate uterine contraction, and theoretically can be catabolized to mutagenic nitrosamines (6,11). Ephedrine causes relaxation of the smooth muscle in the gastrointestinal tract, urinary retention by relaxing the detrusor muscle, and diminishes contraction of the bladder sphincter (11,15). Above ground parts of ephedra seem to cause sweating, but the root seems to inhibit sweating (11).
Adverse Reactions:
Orally, ephedra most commonly causes dizziness, restlessness, anxiety, irritability, personality changes, insomnia, headache, dry mouth, anorexia, nausea, vomiting, flushing, tingling, difficulty urinating, tachycardia, heart palpitations, hyperthermia, and increased blood pressure (1276,3719,6008,6486). Long-term use or use in high doses has also been associated with dependence and tolerance (12,1381). There are also several reports of serious life-threatening or debilitating adverse effects with ephedra products. Psychosis, sometimes prolonged for several months after discontinuation, has been reported (1276,6998). There are reports of myopathies, including myalgia, cardiomyopathy, rhabdomyolysis, eosinophilia-myalgia syndrome (1270), and hypersensitivity myocarditis (1271,6487). Nephrolithiasis (1272) and acute hepatitis (1273) have also been reported. However, the single case of hepatitis is more likely the result of product contamination than due to ephedra itself (1273). Other reported events include chest tightness, myocardial infarction (6486), cardiac arrest and sudden death (1274,6486), stroke, transient ischemic attack, cerebral hemorrhage, seizure, and loss of consciousness (1275,1380,1381,2729,6486). Because most of these events have been described in case reports, it is impossible to determine the overall incidence of these adverse effects. It is also difficult to determine which patient groups might be most likely to experience an adverse event. Patients with a history of cardiovascular disease would be expected to be at a higher risk. However, there have been several reports of serious events in patients with no known pre-existing medical condition. In many cases, ephedra has been used in combination with another stimulant such as caffeine. However, there are also reports of serious adverse effects when ephedra has been used alone. The safety of ephedra is controversial and highly debated. Some claim that ephedra is only unsafe when it is used inappropriately in excessive doses. The supplement industry maintains that ephedra is safe when taken in doses recommended on labeling. However, there are several cases where severe life-threatening or debilitating effects occurred with short-term use of relatively low doses ranging from 20-60 mg ephedra alkaloids per day (6486). Until more is known, warn patients that the potential risks of using ephedra outweigh any potential benefit. Advise patients against using products containing ephedra, especially in combination with other stimulants such as caffeine or if they have a pre-existing condition such as cardiovascular disease.
Interactions with Herbs & Supplements:
HERBS & SUPPLEMENTS WITH STIMULANT PROPERTIES: Use of ephedra and other stimulant herbs such as those containing caffeine can increase the risk of common side effects such as insomnia, jitteriness, tremulousness, dizziness, etc (7). Using ephedra with other stimulants might also increase the risk of more serious adverse effects such as hypertension, myocardial infarction, stroke, and death. There are several reports of serious life-threatening or debilitating adverse events in patients taking ephedra in combination with caffeine and other stimulants (1380,6486). Some herbs and supplements with significant caffeine content include black tea, coffee, cola nut, green tea, guarana, mate, and others.
DIGITALIS: Theoretically, use of ephedra with digitalis might cause cardiac arrhythmias (2).
SECALE ALKALOID DERIVATIVES (Ergot): Theoretically, concomitant use might cause hypertension (2).
Interactions with Drugs:
AMITRIPTYLINE (Elavil): Theoretically, concomitant use might reduce the hypertensive effects of the ephedrine contained in ephedra. Amitriptyline blocks the hypertensive effects of ephedrine (19).
CAFFEINE: Use of ephedra with caffeine can increase the risk of stimulatory adverse effects of ephedra and caffeine (7,19), and possibly enhance thermogenesis and weight loss (19). There is also some evidence that using ephedra with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, and death (1380,6486). Tell patients to avoid taking ephedra with caffeine and other stimulants.
DEXAMETHASONE (Decadron): Theoretically, concomitant use might reduce the effectiveness of dexamethasone, due to the ephedrine contained in ephedra. Ephedrine increases the clearance rate of dexamethasone (19).
DIABETES DRUGS: Ephedra can raise blood glucose levels and interfere with diabetes drug therapy. Monitor blood glucose concentrations closely (19).
DIGOXIN (Lanoxin): Theoretically, concomitant use might cause cardiac arrhythmias (2).
ERGOTAMINE (Migranol, D.H.E. 45, Ergomar): Theoretically, concomitant use of ephedra and ergot alkaloids might cause hypertension, due to the ephedrine contained in ephedra (2).
MONOAMINE OXIDASE INHIBITORS (MAOIs): Contraindicated; concomitant use of ephedra with MAOIs might increase the risk of hypertension (15). A hypertensive crisis and subarachnoid hemorrhage were reported after a patient took a 50 mg dose of ephedrine and an MAOI drug (15).
OXYTOCIN: Theoretically, concomitant use might cause hypertension (2).
RESERPINE: Theoretically, concomitant use might antagonize the indirect sympathomimetic effects of the ephedrine contained in ephedra (19).
THEOPHYLLINE: Theoretically, concomitant use might increase the risk of stimulatory adverse effects of theophylline and ephedrine (contained in ephedra) (7,19).
URINARY ACIDIFIERS: Theoretically, concomitant use of ephedra and urinary acidifying drugs might reduce the ephedrine-related effects of ephedra. Urinary acidifying drugs increase ephedrine excretion (19).
URINARY ALKALINIZERS: Theoretically, concomitant use of ephedra and urinary alkalinizing drugs might increase the ephedrine-related effects of ephedra. Urinary alkalinizing drugs reduce ephedrine excretion (19).
Interactions with Foods:
COFFEE, TEA: Theoretically, concomitant use of large amounts of caffeinated coffee or tea might increase the stimulatory effects and adverse effects of caffeine and the ephedrine contained in ephedra.
Interactions with Lab Tests:
AMPHETAMINE, METHAMPHETAMINE: Ephedra might cause false-positive urine amphetamine or methamphetamine test results. One unpublished case involved a false-positive urine methamphetamine assay in a woman who experienced life-threatening adverse effects associated with the use of an ephedra/guarana product (1381).
EPHEDRINE: Ephedra can cause a positive urine ephedrine test due to its ephedrine content. A case of an athlete whose urine tested positive for norpseudoephedrine was attributed to the use of an herbal supplement labeled to contain ephedra. However, the product might also have contained added norpseudoephedrine as an unlabeled ingredient (1259).
GLUCOSE: Ephedra might increase blood glucose levels and test results (19).
Interactions with Diseases or Conditions:
ANGINA: Contraindicated; ephedra might induce or exacerbate angina due its cardiac stimulant effects (15,512).
ANOREXIA: Contraindicated due to the purported appetite suppressant effects of ephedra. Anorexic patients might be at increased risk for the adverse effects of ephedra due to inadequate nutritional status (12,19).
ANXIETY: Large doses of ephedra might cause or exacerbate anxiety due to its CNS stimulant effects (2,12,15,512).
BENIGN PROSTATIC HYPERTROPHY (BPH): Ephedra might exacerbate urinary retention in patients with BPH due to its effects on the detrusor muscle (15,512).
BULIMIA: Contraindicated; bulimic patients might be at increased risk for the adverse effects of ephedra due to inadequate nutritional status (12,19).
CEREBRAL INSUFFICIENCY: Contraindicated; ephedra might further decrease cerebral blood flow due to its vasoconstrictive effects (2,12,512).
DIABETES: Ephedra might interfere with blood sugar control, and exacerbate high blood pressure and circulatory problems in people with diabetes (15,19,512).
ESSENTIAL TREMOR: Ephedra might exacerbate essential tremor (1715).
HEART DISEASE: Contraindicated; ephedra might cause tachycardia, arrhythmias, or induce angina in patients with heart disease due to its cardiac stimulant effects (15,512).
HYPERTHYROID, THYROTOXICOSIS: Contraindicated; ephedra might stimulate the thyroid and exacerbate hyperthyroid symptoms (2,12,15,512).
HYPERTENSION: Ephedra might exacerbate hypertension (2,12,15,512); contraindicated in uncontrolled hypertension.
KIDNEY STONES: Ephedra and ephedrine can cause kidney stones (1272).
NARROW-ANGLE GLAUCOMA: Ephedra might exacerbate narrow-angle (angle-closure) glaucoma by causing mydriasis (2,12,15,512).
PHEOCHROMOCYTOMA: Contraindicated; ephedra might exacerbate the symptoms of pheochromocytoma (2).
URINARY RETENTION: Large doses of ephedra might exacerbate urinary retention due its effects on the detrusor muscle (2,12,15,512).
Dosage/Administration:
ORAL: For reducing weight in obese patients, ephedra 12 mg in combination with guarana 40 mg three times daily plus 17 other vitamins, minerals, and supplements (Metabolife 356) has been used (3719). The typical dose of ephedra is 15-20 mg of the ephedra alkaloids calculated as ephedrine taken up to 3 times daily (2,7,12,6486). Doses up to 300 mg per day have been used (2,7,12). However, doses as low as 12-36 mg per day have been associated with severe adverse effects (see Adverse Reactions). One cup of ephedra tea is also commonly taken 3 times per day. The tea is prepared by steeping 1-4 grams in 150 mL boiling water for 5-10 minutes and then straining (18). The tincture (1:1) is usually given as 5 grams per dose (18). Another tincture (1:4) is given 6-8 mL three times per day (18). The typical dose of the extract is 1-3 mL three times per day (18). For children over the age of 6 years, some sources suggest a dose of 0.5 mg/kg up to a maximum of 2 mg/kg per day (2,7,12), but due to safety concerns, ephedra should not be used in children.
Comments:
Mormon tea and ephedra are often confused. Mormon tea or American ephedra comes from Ephedra nevadensis and ephedra or ma huang comes primarily from Ephedra sinica. Mormon tea is alkaloid-free and lacks both the therapeutic effects and the toxicity of ephedrine (3,12).
There has been a lot of debate about the safety of ephedra. In June of 1997, the FDA proposed restrictions on the ephedrine content of dietary supplements, new warning labels for ephedra alkaloid-containing products, and a prohibition on combination products containing ephedra and other natural stimulants, such as guarana and cola nut, both of which contain significant amounts of caffeine (2729). These proposals were dropped after the link between ephedra use and serious adverse effects was challenged by the General Accounting Office (GAO) and the dietary supplement industry (1381). The FDA is currently reviewing numerous adverse event reports involving ephedra alkaloid-containing products, with 140 of the reports receiving in-depth clinical review by FDA and outside experts (1381,5047,6486). Findings from experts outside the FDA support the FDA’s initial finding that ephedra is likely the cause of many of the 140 reports receiving in-depth clinical review (6486). Restrictions on ephedra products have not yet been implemented by the FDA. However, 28 states have independently implemented varying restrictions on ephedra use (6487).
Ephedra is now being marketed as a recreational drug “herbal ecstasy.” The FDA has announced that ephedra products marketed as recreational drugs are unapproved and misbranded drugs subject to seizure and injunction (5047).
Formulated Solutions is offline   Reply With Quote