Two capsules contain: Bitter Orange fruit, Magnolia bark, Chinese Rhubarb root, Dwarf-Lilyturf root, Apricot seed, White Peony root, Mirabilatum .
Brand name products often contain multiple ingredients. To read detailed information about each ingredient, click on the link for the individual ingredient shown above.
Below is general information about the effectiveness of the known ingredients contained in the product BoweLax. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
There is insufficient reliable information available about the effectiveness of apricot.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product BoweLax. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
LIKELY SAFE ...when apricot fruit or juice is consumed as food. There is insufficient reliable information available about the safety of apricot fruit, juice, or leaves when used orally for medicinal purposes.
PREGNANCY AND LACTATION: LIKELY SAFE
when apricot fruit or juice is consumed as food.
There is insufficient reliable information available about the safety of apricot fruit, juice, or leaves when used orally for medicinal purposes; avoid use.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Bitter orange has Generally Recognized as Safe (GRAS) status in the US (4912,35751).
POSSIBLY SAFE ...when bitter orange essential oil is used topically or by inhalation as aromatherapy (6972,7107,98331,104186,104187,108642).
POSSIBLY UNSAFE ...when used orally for medicinal purposes. Although single doses of synephrine, or low daily doses used short-term, may be safe in healthy adults (2040,11269,15381,35757,35759,91681,97256,98332), laboratory analyses raise concerns that many marketed bitter orange products contain higher amounts of synephrine and other natural and synthetic amines than on the label, increasing the risk for serious stimulant-related adverse effects (104185). Additionally, there is a lack of agreement regarding a safe daily dose of synephrine. Health Canada has approved 50 mg of p-synephrine daily when used alone, or 40 mg of p-synephrine in combination with up to 320 mg of caffeine daily in healthy adults (91684). The Federal Institute for Risk Assessment in Germany recommends that supplements should provide no more than 6.7 mg of synephrine daily. This recommendation is meant to ensure that patients who frequently consume synephrine in conventional foods will receive no more than 25.7 mg daily (91290). These limits are intended to reduce the risk for serious adverse effects. There have been several case reports of ischemic stroke and cardiotoxicity including tachyarrhythmia, cardiac arrest, syncope, angina, myocardial infarction, ventricular arrhythmia, and death in otherwise healthy patients who have taken bitter orange extract alone or in combination with other stimulants such as caffeine (2040,6979,12030,13039,13067,14326,14342,91680).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in the amounts found in foods.
Bitter orange has Generally Recognized as Safe (GRAS) status in the US (4912).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally for medicinal purposes.
There are case reports of cardiotoxicity including tachyarrhythmia, syncope, and myocardial infarction in otherwise healthy adults who have taken bitter orange extract alone or in combination with other stimulants such as caffeine (2040,6979,12030,13039,13067,14326,14342,91680). The effects of bitter orange during lactation are unknown; avoid use.
POSSIBLY SAFE ...when used orally and appropriately, short-term. A specific product containing magnolia extract and phellodendron extract (Relora, Next Pharmaceuticals, Inc.) has been used with apparent safety in clinical trials at a dose of 250 mg two to three times daily for up to 6 weeks (14349,34246,94904). ...when used topically in a toothpaste for up to 6 months (92464).
PREGNANCY: UNSAFE
when the magnolia flower bud is used orally due to reports of uterine stimulant activity (11953).
There is insufficient reliable information available about the safety of using magnolia bark during pregnancy; avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally and appropriately, short term. Total glucosides of peony has been used with apparent safety in doses of up to 1800 mg daily for up to 12 months (92786,97949,97950,98466,100992,110432,112861,112862). Peony root extract has been used with apparent safety at a dose of 2250 mg daily for up to 3 months (97216). There is insufficient reliable information available about the safety of peony when used orally, topically, or rectally, long-term.
CHILDREN: POSSIBLY SAFE
when used orally and appropriately, short-term.
Total glucosides of peony has been used with apparent safety in children 1.5-4 years of age at doses up to 180 mg/kg daily or 1.2 grams daily for up to 12 months (92785). Peony root extract 40 mg/kg daily has also been used with apparent safety in children 1-14 years of age for 4 weeks (106851).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Preliminary research suggests that peony can cause uterine contractions (13400). However, other preliminary research suggests a combination of peony and angelica with or without motherwort, banksias rose, and ligustica, might be safe (11015,48433). Until more is known, avoid use.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when the stalk is used in amounts commonly found in foods and when the root is used as a food flavoring. Rhubarb has Generally Recognized as Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when the root or rhizome is used orally and appropriately in medicinal amounts for up to 2 years (92294,92295,92297). ...when the stalk is used orally and appropriately in medicinal amounts for up to 4 weeks (71351,71363,97920). ...when used topically and appropriately (10437,97919).
POSSIBLY UNSAFE ...when the leaf is used orally. Rhubarb leaf contains oxalic acid and soluble oxalate, which can cause abdominal pain, burning of the mouth and throat, diarrhea, nausea, vomiting, seizures, and death (17).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used in medicinal amounts, rhubarb root is a stimulant laxative; avoid using (12).
Below is general information about the interactions of the known ingredients contained in the product BoweLax. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Theoretically, bitter orange might increase the risk of hypoglycemia when taken with antidiabetes drugs.
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Some clinical research shows that drinking a tea containing bitter orange and Indian snakeroot reduces fasting and postprandial glucose levels in patients with type 2 diabetes who are using antidiabetes drugs (35751). However, it is unclear if these effects are due to bitter orange, Indian snakeroot, or the combination. An animal study also shows that p-synephrine in combination with gliclazide , a sulfonylurea, causes an additional 20% to 44% decrease in glucose levels when compared with gliclazide alone (95658).
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Bitter orange might increase blood pressure and heart rate when taken with caffeine.
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Bitter orange might affect colchicine levels.
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Colchicine is a substrate of P-glycoprotein and cytochrome P450 3A4 (CYP3A4). Bitter orange has been reported to inhibit CYP3A4 and increase levels of CYP3A4 substrates (7029,11362,93470). However, one small clinical study in healthy adults shows that drinking bitter orange juice 240 mL twice daily for 4 days and taking a single dose of colchicine 0.6 mg on the 4th day decreases colchicine peak serum levels by 24%, time to peak serum level by 1 hour, and overall exposure to colchicine by 20% (35762). The clinical significance of this finding is unclear.
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Theoretically, bitter orange might increase levels of drug metabolized by CYP2D6.
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In vitro research shows that octopamine, a constituent of bitter orange, weakly inhibits CYP2D6 enzymes (91878). This effect has not been reported in humans.
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Bitter orange might increase levels of drugs metabolized by CYP3A4.
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Small clinical studies suggest that single or multiple doses of freshly squeezed bitter orange juice 200-240 mL can inhibit CYP3A4 metabolism of drugs (7029,11362,93470), causing increased drug levels and potentially increasing the risk of adverse effects. However, the extent of the effect of bitter orange on CYP3A4-mediated drug interactions is unknown. Some evidence suggests that bitter orange selectively inhibits intestinal CYP3A4, but not hepatic CYP3A4. Its effect on P-glycoprotein, which strongly overlaps with CYP3A4 interactions, is unclear (7029,11269,11270,11362). One small clinical study shows that drinking 8 ounces of freshly squeezed bitter orange juice has no effect on cyclosporine, which seems to be more dependent on hepatic CYP3A4 and P-glycoprotein than intestinal CYP3A4 (11270).
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Bitter orange might increase blood levels of dextromethorphan.
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One small clinical study shows that bitter orange juice increases dextromethorphan levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition (11362). Theoretically, bitter orange might increase the risk for dextromethorphan-related adverse effects.
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Bitter orange might increase blood levels of felodipine.
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One small clinical study shows that bitter orange juice increases felodipine levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition (7029). Theoretically, bitter orange might increase the risk for felodipine-related adverse effects.
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Bitter orange might increase blood levels of indinavir.
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One small clinical study shows that bitter orange juice slightly increases indinavir levels, but this effect is likely to be clinically insignificant. Bitter orange selectively inhibits intestinal cytochrome P450 3A4 (CYP3A4); however, the metabolism of indinavir seems to be more dependent on hepatic CYP3A4 (11269). The effect of bitter orange on other protease inhibitors has not been studied.
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Bitter orange might increase blood levels of midazolam.
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One small clinical study shows that bitter orange juice can increase midazolam levels, likely through inhibition of cytochrome P450 3A4 (CYP3A4) (7029). Theoretically, bitter orange might increase the risk of midazolam-related adverse effects.
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Theoretically, taking MAOIs with synephrine-containing bitter orange preparations might increase the hypertensive effects of synephrine, potentially leading to hypertensive crisis.
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Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.
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One case report suggests that taking bitter orange in combination with other stimulants such as caffeine might prolong the QT interval in some patients (13039).
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Bitter orange juice might increase blood levels of sildenafil.
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A small clinical study in healthy adult males shows that drinking freshly squeezed bitter orange juice 250 mL daily for 3 days and taking a single dose of sildenafil 50 mg on the 3rd day increases the peak plasma concentration of sildenafil by 18% and the overall exposure to sildenafil by 44%. Theoretically, this may be due to inhibition of cytochrome P450 3A4 by bitter orange (93470).
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Theoretically, bitter orange might increase the risk of hypertension and adverse cardiovascular effects when taken with stimulant drugs.
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Theoretically, magnolia might have additive effects and increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
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In vitro research shows that the chemicals magnolol and honokiol, isolated from magnolia bark, inhibit platelet aggregation that is experimentally induced by collagen and arachidonic acid. However, they do not inhibit platelet aggregation that is induced by adenosine diphosphate, platelet-activating factor, or thrombin (18273). This interaction has not been reported in humans.
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Theoretically, concomitant use of large doses of magnolia bark and CNS depressants might have additive effects.
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Theoretically, combining peony with anticoagulant or antiplatelet drugs might increase the risk of bleeding.
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In vitro research suggests that peony might have antiplatelet, anticoagulant, and antithrombotic effects (92787).
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Theoretically, peony might increase the levels and clinical effects of clozapine.
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In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on cytochromes P450 (CYP) 1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, peony might interfere with contraceptive drugs due to competition for estrogen receptors.
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In vitro and animal research shows that peony extract has estrogenic activity (100990). Concomitant use might also increase the risk for estrogen-related adverse effects.
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Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP1A2.
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In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, use of peony may increase the levels and clinical effects of drugs metabolized by CYP3A4.
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In vitro research shows that peony suppresses the metabolism of clozapine via weak-to-moderate inhibitory effects on CYP1A2 and CYP3A4 (92790). This effect has not been reported in humans.
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Theoretically, concomitant use of large amounts of peony might interfere with hormone replacement therapy and/or increase the risk for estrogen-related adverse effects.
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In vitro and animal research shows that peony extract has estrogenic activity (100990). Theoretically, peony might compete for estrogen receptors and/or cause additive estrogenic effects.
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Theoretically, peony might reduce the levels and clinical effects of phenytoin.
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Animal research shows that taking peony root reduces levels of phenytoin (8657). Some researchers suggest that peony root might affect cytochrome P450 (CYP) 2C9, which metabolizes phenytoin. However, preliminary research in humans shows that peony root does not alter levels of losartan (Cozaar), which is also metabolized by CYP2C9 (11480).
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Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia when taken with corticosteroids.
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Theoretically, taking rhubarb with cyclosporine might reduce cyclosporine levels.
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Animal research shows that co-administration of rhubarb decoction 0.25 or 1 gram/kg with cyclosporine 2.5 mg/kg, decreases cyclosporine maximum plasma concentration and overall exposure levels when compared with taking cyclosporine alone. The authors theorize that rhubarb might reduce cyclosporine bioavailability by inducing of P-glycoprotein and/or cytochrome P450 3A4 (92304). However, since rhubarb was administered as a single oral dose and enzyme induction usually occurs after multiple doses, it is possible that cyclosporine absorption was actually reduced via rhubarb's stimulant laxative effects (12). Also, the composition of the rhubarb decoction was not described.
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Theoretically, overuse of rhubarb might increase the risk of adverse effects when taken with digoxin.
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Theoretically, frequent and high doses of rhubarb might increase the risk of hypokalemia.
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Theoretically, concomitant use of rhubarb with potentially hepatotoxic drugs might increase the risk of developing liver damage.
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Theoretically, long-term use of anthraquinones from rhubarb might increase the risk of nephrotoxicity when used with nephrotoxic drugs.
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The anthraquinone constituents of rhubarb have been shown to induce nephrotoxicity in animal research (71322). Additionally, in a case report, a 23-year old female presented with kidney failure after taking 6 tablets of a proprietary slimming agent (found to contain the anthraquinones emodin and aloe-emodin from rhubarb) daily for 6 weeks and then adding diclofenac 25 mg 4 times daily for 2 days. The authors postulate that the anthraquinone constituents of rhubarb contributed to the renal dysfunction, and the addition of diclofenac, a nephrotoxic drug, led to renal failure (15257). Until more is known, advise patients to avoid taking rhubarb if they are taking other potentially nephrotoxic drugs.
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Theoretically, rhubarb might increase the risk for fluid and electrolyte loss when taken with other stimulant laxatives.
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Theoretically, excessive use of rhubarb might increase the risk of bleeding when taken with warfarin.
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Below is general information about the adverse effects of the known ingredients contained in the product BoweLax. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General ...No adverse effects have been reported; however, a thorough evaluation of safety outcomes has not been conducted.
General
...Orally, bitter orange might be unsafe when used in medicinal amounts.
Topically and when inhaled as aromatherapy, bitter orange seems to be well tolerated.
Most Common Adverse Effects:
Orally: Hypertension and tachycardia, particularly when used in combination with caffeine and/or other stimulant ingredients.
Topically: Skin irritation.
Serious Adverse Effects (Rare):
Orally: Myocardial infarction, QT prolongation, seizures, stroke, syncope, tachyarrhythmia, and ventricular fibrillation have been reported in patients taking bitter orange in combination with other ingredients. It is unclear if these effects are due to bitter orange, other ingredients, or the combination.
Cardiovascular
...Bitter orange, which contains adrenergic agonists synephrine and octopamine, may cause hypertension and cardiovascular toxicity when taken orally (2040,6969,6979).
Studies evaluating the effect of bitter orange on cardiovascular parameters have been mixed. Several studies show that taking bitter orange alone or in combination with caffeine increases blood pressure and heart rate. In one clinical study, bitter orange in combination with caffeine increased systolic and diastolic blood pressure and heart rate in otherwise healthy normotensive adults (13657). In another study, a single dose of bitter orange 900 mg, standardized to 6% synephrine (54 mg), also increased systolic and diastolic blood pressure and heart rate for up to 5 hours in young, healthy adults (13774). Using half that dose of bitter orange and providing half as much synephrine, did not seem to significantly increase blood pressure or QT interval in healthy adults (14311). Increased diastolic, but not systolic, blood pressure or heart rate also occurred in a clinical trial involving a specific supplement containing synephrine 21 mg and caffeine 304 mg (Ripped Fuel Extreme Cut, Twinlab) (35743). Synephrine given intravenously to males increased systolic blood pressure, but lacked an effect on diastolic blood pressure or heart rate (12193).
In clinical research and case reports, tachycardia, tachyarrhythmia, QT prolongation, ischemic stroke, variant angina, and myocardial infarction have occurred with use of bitter orange or synephrine-containing multi-ingredient products (12030,13039,13067,13091,13657,14326,35749,91680). In one case report, a combination product containing bitter orange may have masked bradycardia and hypotension while exacerbating weight loss in a 16 year-old female with an eating disorder taking the product for weight loss (35740). From 1998 to 2004, Health Canada received 16 reports of serious adverse cardiovascular reactions such as tachycardia, cardiac arrest, ventricular fibrillation, blackout, and collapse. In two of these cases, the patient died. In almost all of these cases, bitter orange was combined with another stimulant such as caffeine, ephedrine, or both (14342).
Other research has found no significant effect of bitter orange on blood pressure or heart rate. Several clinical studies have reported that, when taken as a single dose or in divided doses ranging from 20-100 mg for one day, p-synephrine had no significant effect on blood pressure, heart rate, electrocardiogram results or adverse cardiovascular events in healthy adults (35772,91681,91681,95659,101708) Similarly, no difference in blood pressure, heart rate or electrocardiogram results were reported when p-synephrine from bitter orange (Advantra Z/Kinetic; Nutratech/Novel Ingredients Inc.) was taken for 6 weeks in healthy patients (11268). Another clinical study showed no significant effect of bitter orange (Nutratech Inc.), standardized to synephrine 20 mg, on blood pressure or heart rate when taken daily for 8 weeks in healthy males (95656). In other research, changes in blood pressure, heart rate, or QTc interval were lacking when bitter orange was given alone or in combination with caffeine and green tea (14311,35753,35755,35764,35769,35770). In one study of healthy adults, taking a single dose of p-synephrine 103 mg actually reduced mean diastolic blood pressure by 0.4-4 mmHg at 1 and 2 hours after administration when compared with placebo (95659).
A meta-analysis of clinical trials in adults with or without obesity suggests that taking p-synephrine 6-214 mg orally daily does not affect blood pressure or heart rate when used short-term, but modestly increases blood pressure and heart rate when taken for 56-60 days (109950).
The effect of bitter orange on blood pressure, heart rate, and electrocardiogram results in patients with underlying conditions, particularly cardiovascular disease, is unknown and requires further study.
Dermatologic ...Photosensitivity may occur, particularly in fair-skinned people (11909). In a clinical trial, topical application with bitter orange essential oil resulted in irritation (6972).
Endocrine ...Some clinical research shows that taking a specific supplement containing 21 mg of synephrine and 304 mg of caffeine (Ripped Fuel Extreme Cut, Twinlab) increases levels of postprandial glucose (35743). Other preliminary clinical research shows that taking a specific pre-workout supplement (Cellucor C4 Pre-Workout, Nutrabolt) along with a bitter orange extract standardized for synephrine 20 mg (Nutratech Inc.) 30 minutes once before exercise causes a significant 12% increase in glucose (95657); however, there is no difference in blood glucose when compared with placebo when this combination is taken daily for 8 weeks (95656). The effect of bitter orange itself is unclear.
Gastrointestinal ...Bitter orange has been linked to a report of ischemic colitis. In one case, a 52-year-old female developed ischemic colitis after taking a bitter orange-containing supplement (NaturalMax Skinny Fast, Nutraceutical Corporation) for a week. Symptoms resolved within 48 hours after discontinuing the supplement (15186). As this product contains various ingredients, the effect of bitter orange itself is unclear.
Musculoskeletal ...Unsteady gait has been noted in one case report of a patient taking bitter orange (13091). In another case, an otherwise healthy, Black male with sickle cell trait, developed severe rhabdomyolysis following ingestion of a specific weight loss product (Lipo 6, Nutrex Research Inc.), which contained synephrine and caffeine (16054). However, other preliminary clinical research shows that taking a specific pre-workout supplement (Cellucor C4 Pre-Workout, Nutrabolt) along with a bitter orange extract standardized for synephrine 20 mg (Nutratech Inc.), taken 30 minutes once before exercise (95657) or daily for 8 weeks, does not affect creatine kinase or serum creatinine levels when compared with placebo (95656). As these products contain various ingredients, the effect of bitter orange itself is unclear.
Neurologic/CNS ...Dizziness, difficulty in concentrating, memory loss, syncope, seizure, and stroke have been noted in case reports following bitter orange administration (13091,13039). Theoretically, bitter orange may trigger a migraine or cluster headache due to its synephrine and octopamine content (35768). When used as aromatherapy, bitter orange essential oil has also been reported to cause headache in some patients (104187). Sprint athletes taking the bitter orange constituent p-synephrine 3 mg/kg (Synephrine HCL 99%, Nutrition Power) 60 minutes before exercises and sprinting reported more nervousness (mean difference 0.9) when compared with placebo on a Likert scale. Although statistically significant, this difference is not considered clinically significant (95655).
General
...Orally, magnolia seems to be well tolerated.
Most Common Adverse Effects:
Topically: Contact dermatitis.
Dermatologic ...Topically, magnolia bark has been associated with reports of allergic contact dermatitis (92463,92468,95030,110709). In several cases, the use of anti-aging facial creams containing magnolia bark extract was associated with allergic contact dermatitis of the face (92463,92468,95030). In one case, the use of a vaginal gel containing magnolia bark extract was associated with allergic contact dermatitis of the vulva (110709). Symptoms typically resolve with the use of topical corticosteroids and discontinuation of magnolia bark extract (95030,110709). Patch testing suggests that the magnolia bark extract constituents magnolol and honokiol are responsible for this adverse effect (110709).
Endocrine ...In a clinical trial of an oral combination product containing extracts of magnolia and phellodendron, one patient reported thyroid dysfunction (14349). However, it's not known if this side effect is related to magnolia or some other factor.
Gastrointestinal ...In a clinical trial of an oral combination product containing extracts of magnolia and phellodendron, one patient reported heartburn (14349). However, it's not known if this side effect is related to magnolia or some other factor.
Neurologic/CNS ...In a clinical trial of an oral combination product containing extracts of magnolia and phellodendron, one patient reported shaking hands and perilabial numbness. Another patient reported fatigue and headache (14349). However, it's not known if these side effects are related to magnolia or some other factor.
Psychiatric ...In a clinical trial of an oral combination product containing extracts of magnolia and phellodendron, one patient reported sexual dysfunction (14349). However, it's not known if this side effect is related to magnolia or some other factor.
General
...Orally, peony seems to be well tolerated when used alone and as part of Chinese herbal formulas.
Most Common Adverse Effects:
Orally: Abdominal distension, anorexia, diarrhea, gastrointestinal discomfort, nausea.
Topically: Dermatitis.
Dermatologic ...Topically, peony has been reported to cause contact dermatitis (13555).
Endocrine ...Orally, a specific traditional Chinese medicine preparation called DDT has been reported to lower follicle-stimulating hormone (FSH) levels and increase estradiol levels. It is not known if this effect is due to peony or the other ingredients (48404). Another specific traditional Chinese medicine preparation, Toki-shakuyaku-san, has been reported to increase plasma progesterone levels in some patients. It is not known if this effect is due to peony or the other ingredients (15294).
Gastrointestinal ...Orally, peony and total glucosides of peony (TGP) have been reported to cause gastrointestinal discomfort, including abdominal distension, anorexia, diarrhea, and nausea, in some patients (13538,92785,97949,98466,100992). In one clinical study, diarrhea was reported in 5% of patients taking TGP 600 mg three times daily for 24 weeks versus 1% of patients taking placebo (100992).
Hematologic ...Orally, there is one case report of easy gum bleeding, epistaxis, and skin bruising with an international normalized ratio (INR) above 6 in a 61-year-old male who was previously stable on warfarin therapy. This patient had switched from one brand of quilinggao, a popular Chinese herbal product, to another brand 5 days prior. This product contained Fritillaria spp. (beimu), Paeonia rubra, Chinese peony (chishao), Lonicera japonica (jinyinhua), and Poncirus trifoliata (jishi). The patient's INR decreased to 1.9 after temporary withdrawal of warfarin therapy. Upon re-initiation of quilinggao, his INR increased to 5.2. It is not known if the increased INR is due to peony or the other ingredients (68343).
General
...Orally, rhubarb root and stalk are well tolerated when used in food amounts and seem to be well tolerated when used in medicinal amounts.
Rhubarb leaf contains oxalic acid and can be toxic. Topically, rhubarb seems to be well tolerated.
Most Common Adverse Effects:
Orally: Cramps, diarrhea, gastrointestinal discomfort, nausea, vomiting.
Topically: Rash.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis.
Cardiovascular ...Orally, chronic use or abuse of rhubarb can cause arrhythmias (12).
Dermatologic ...Orally, rhubarb taken alone or in combination with other ingredients has been reported to cause rash (71315,71342). Topically, short term application of a specific product (Pyralvex) containing rhubarb, salicylic acid, and ethanol to the gums has been reported to cause slight burning and dark discoloration of the gums in approximately 1% of patients (71369). It is unclear if this effect is due to rhubarb, other ingredients, or the combination.
Endocrine ...Orally, chronic use or abuse of rhubarb can cause electrolyte loss (especially potassium), hyperaldosteronism, albuminuria, and edema (12).
Gastrointestinal
...Orally, rhubarb can cause cramp-like or spasmodic gastrointestinal discomfort, watery diarrhea, and uterine contractions (18).
Rhubarb, alone or in combination with other ingredients, has also been reported to cause bloating, nausea, diarrhea, vomiting, and stomach upset or pain in clinical studies. Diarrhea is more common with a starting dose of at least 3 grams of extract (71315,71329,71339,71340,71341,71342,71373,92300). Chronic use or abuse of rhubarb can cause inhibition of gastric motility and pseudomelanosis coli (pigment spots in the intestinal mucosa) (12,6138).
Although some research suggests that rhubarb and other anthranoid laxatives might increase the risk of colorectal cancer due to pseudomelanosis coli (30743), more recent research suggests that this condition is harmless, typically reversed with rhubarb discontinuation, and not associated with an increased risk for colorectal adenoma or carcinoma (6138).
Hematologic ...Orally, chronic use or abuse of rhubarb can cause hematuria (12).
Hepatic ...Orally, chronic use of anthraquinone-containing products, such as rhubarb, has been associated with hepatotoxicity (15257). Use of rhubarb specifically has been linked to at least 24 reports of liver injury, although details on the dose of rhubarb and duration of use in these cases are not clear (100963). In one clinical study, rhubarb, taken in combination with other ingredients, has been reported to cause mild to moderate elevations of serum alanine aminotransferase (71315).
Immunologic ...Orally, rhubarb has rarely been reported to cause anaphylaxis (18).
Musculoskeletal ...Orally, chronic use or abuse of rhubarb can cause accelerated bone deterioration and muscular weakness (12).
Renal ...Orally, chronic use or abuse of rhubarb can cause electrolyte loss (especially potassium), albuminuria, hematuria, dehydration, and nephropathies (12). There is one case report of renal failure in a patient who took a product containing rhubarb for six weeks. The patient presented with renal failure two days after starting diclofenac, which is known to have nephrotoxic effects. It is hypothesized that the combination of diclofenac with the anthraquinone constituents of rhubarb precipitated renal dysfunction (15257).
