Ispaghula
Psyllium/Drug Interactions:
GeneralGeneral: Experts state that soluble fibers may decrease the absorption of drugs (171) and a systematic review on drug interactions with psyllium was published (conclusions lacking) (172). AnalgesicsAnalgesics: According to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.AntibioticsAntibiotics: According to secondary sources, antibiotics such as tetracyclines and nitrofurantoin may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.AntibronchospasticsAntibronchospastics: Wheezing has been reported as an allergic manifestation in individuals with repeated psyllium exposure (40; 1; 2; 41). In other clinical research, coughing has been reported (36; 41). Anticoagulants and antiplateletsAnticoagulants and antiplatelets: According to secondary sources, psyllium may reduce the absorption of anticoagulant and antiplatelet agents. However, effects on warfarin levels by coadministered psyllium were lacking in human research (60). Antidepressant agents, tricyclic (TCAs)Antidepressant agents, tricyclic (TCAs): Dietary fiber has been shown to lower the blood levels and effectiveness of tricyclic antidepressant medications in human research (68). Reduced dietary fiber intake increased the blood levels and improved symptoms in these individuals. Antidiabetic agentsAntidiabetic agents: In human research, in the presence or absence of other hypoglycemic agents, psyllium decreased plasma glucose and HbA1C (43; 49; 41; 42; 47; 44; 45; 46; 48; 50; 51; 52; 53; 54; 55; 56); however, acute effects were lacking in some available studies (57). Long-term effects of psyllium on glycemic indices were mixed (35; 34; 58; 59; 56). Also, in human research, psyllium decreased insulin levels (55). According to a systematic review, in combination with antidiabetic agents, psyllium had beneficial effects on blood lipids (35). AntidiarrhealsAntidiarrheals: In human research, psyllium increased defecation frequency and stool weight and decreased transit time (102; 38; 115). However, in other human studies, psyllium was shown to have an antidiarrheal effect, which was attributed to its ability to increase the water-holding capacity and viscosity of stools, thereby delaying gastric emptying and improving stool consistency (104; 105; 106; 107). Antigout agentsAntigout agents: According to secondary sources, psyllium may increase the effects of antigout agents.Antihemorrhoidal agentsAntihemorrhoidal agents: In human research, psyllium-containing products reduced the symptoms of hemorrhoids in some (122; 123), but not all (124), studies. AntihistaminesAntihistamines: Rhinitis and wheezing have been reported as allergic manifestations in individuals with repeated psyllium exposures (40; 1; 2; 41). AntihypertensivesAntihypertensives: In human research, psyllium reduced SBP and/or DBP (32; 33; 34; 35). Anti-inflammatory agentsAnti-inflammatory agents: According to a systematic review of clinical trials, psyllium reduced levels of C-reactive protein (CRP) (173). In addition, according to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. Antilipemic agents, bile acid sequestrantsAntilipemic agents, bile acid sequestrants: In human research, psyllium decreased total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and the ratio of LDL to high-density lipoprotein (HDL) (30; 174; 132; 78; 42; 39; 131; 140; 125; 43; 143; 84; 92; 26; 139; 95; 90; 130; 35; 58; 34; 59; 109; 175). With respect to triglyceride (TG) levels (30; 39; 135; 89; 125; 92; 90; 43; 35; 34) and HDL (30; 174; 132; 39; 89; 125; 92; 90; 43; 130; 29), evidence is mixed, with most studies in support of a lack of effect on TG levels and increased, decreased, or no effects on HDL cholesterol. In human research, psyllium plus cholestyramine provided a modest but nonsignificant reduction in TC and LDL; this combination reduced constipation, abdominal discomfort, and heartburn significantly more than in the group that continued on cholestyramine alone (139). However, in other human research, statistically significant lipid reduction was lacking after the use of colestipol and psyllium (135). In human research, in combination with simvastatin, psyllium reduced TC, LDL, and apolipoprotein (apo) B to a greater extent than simvastatin alone (109). In animal research, LDL cholesterol was reduced to a greater extent with high-dose cholestyramine compared to a lower dose of that agent plus psyllium, and this combination reversed cholestyramine-induced LDL receptor suppression and reduced hepatic cholesterol content (176). Antineoplastic agentsAntineoplastic agents: In animal research, psyllium has been shown to improve the chemoprotective effect of wheat bran (177). In other animal research, psyllium has been shown to help maintain normal cell proliferation in the colon (178; 179). In human research, psyllium fiber has been shown to be converted to butyrate, which appears to be important in protecting against colon cancer (112). In vitro, fermentation products of the Plantago ovata husk (fermented with colonic bacteria) induced apoptosis of cancer cell lines (180). Contrary to these findings, in patients with colorectal adenoma, there was a significant increase in adenoma recurrence risk in subjects receiving ispaghula husk vs. placebo (98). Antiobesity agentsAntiobesity agents: In the popular press, psyllium has been suggested as a possible weight loss aid; however, conclusive results from clinical trials are lacking (43; 66; 35; 58; 34). In human research, psyllium increased satiety and decreased food intake (155) and increased the postmeal respiratory quotient (156); however, an effect on satiety was lacking in a separate study (156). In a clinical trial, psyllium use resulted in a reduction in the ratio of android fat to gynoid fat (58). In human research, psyllium coadministered with orlistat vs. orlistat alone resulted in fewer gastrointestinal events, such as diarrhea and oily discharge, in the combination therapy group (181). AntipsychoticsAntipsychotics: In epidemiological research, concomitant use of Chinese medicine and antipsychotics in schizophrenic patients suggested that Semen Plantaginis in concomitant use with quetiapine, clozapine, and olanzapine was associated with increased risk of adverse outcomes (182). In human research, psyllium decreased the plasma levels and effectiveness of lithium (62; 63). Psyllium should be separated from lithium by at least two hours to reduce the likelihood of this interaction. AntipyreticsAntipyretics: According to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.Antiseizure agentsAntiseizure agents: In human research, psyllium may decrease the absorption and concentration of carbamazepine (61). If patients are treated with carbamazepine and psyllium, their administration times should be separated as far as possible, and plasma levels of carbamazepine should be monitored.CarbamazepineCarbamazepine: In human research, psyllium decreased the absorption and concentration of carbamazepine (61). If patients are treated with carbamazepine and psyllium, their administration times should be separated as far as possible, and plasma levels of carbamazepine should be monitored.Cardiac glycosidesCardiac glycosides: In human research, psyllium reduced the area under the curve (AUC) of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin levels was lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). Cardiovascular agentsCardiovascular agents: In human research, psyllium reduced the AUC of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin levels was lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). According to secondary sources, potassium-sparing diuretics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. Colonoscopy preparationColonoscopy preparation: In human research, effects of psyllium on the tolerability of a standard polyethylene glycol-based lavage preparation for colonoscopy were lacking; however, the efficacy of the bowel preparation was reduced (168). Dermatologic agentsDermatologic agents: In clinical research, a rash was reported in the psyllium group (36). DigoxinDigoxin: In human research, psyllium reduced the AUC of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin levels was lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). According to secondary sources, potassium-sparing diuretics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. FludrocortisoneFludrocortisone: Psyllium has induced adrenal crisis in an individual with adrenal insufficiency; this effect was hypothesized to be caused by inhibited gastrointestinal absorption of prednisolone and/or fludrocortisone caused by psyllium (71). Gastrointestinal agentsGastrointestinal agents: In human research, psyllium ingestion increased defecation frequency and stool weight, and decreased transit time (102; 38; 115). Experts have suggested that psyllium may have additive effects when taken with laxatives (105; 99; 100; 101; 102; 103) or, based on mechanism of action, antidiarrheals (104; 105; 106; 107). Improvements in symptoms of anorectal fissures have been reported following psyllium administration (185), and results from early clinical research suggested that psyllium reduced the number of surgeries necessary to heal anal fissures (111). Gastrointestinal adverse effects have been commonly reported following use of psyllium (9; 10; 11; 77; 78; 79; 80; 81; 82; 83; 43; 84; 36; 47; 85; 38; 41; 86; 87; 88; 89; 90; 91; 92; 93; 94; 95; 39; 96; 97; 72; 73; 74; 75; 76). HematologicsHematologics: Systemic eosinophilia without other allergic manifestations has been attributed to psyllium-containing bulk laxative therapy in a 60 year-old woman being treated for irritable bowel syndrome (37). Hydrophilic agentsHydrophilic agents: According to secondary sources, psyllium may theoretically increase the effects of hydrophilic agents. Psyllium is hydrophilic because of its high content of hemicelluloses (186; 2). LaxativesLaxatives: In human research, increased defecation frequency and stool weight and decreased transit time occurred (102; 38; 115). According to secondary sources, experts recommend avoiding other laxatives when taking psyllium, because the laxative effects may be increased. LithiumLithium: In human research, psyllium decreased the plasma levels and effectiveness of lithium (62; 63). Psyllium should be separated from lithium by at least two hours to reduce the likelihood of this interaction. Musculoskeletal agentsMusculoskeletal agents: Back pain was reported in 9% of patients in the psyllium group vs. 0% of patients in the placebo group in a clinical trial (38). Exacerbation of gout occurred in one patient (39). Neurologic agentsNeurologic agents: Recurrence of Tourette's syndrome occurred in one patient (39). OrlistatOrlistat: In human research, psyllium coadministered with orlistat vs. orlistat alone resulted in fewer gastrointestinal events, such as diarrhea and oily discharge, in the combination therapy group (181). Potassium-sparing diureticsPotassium-sparing diuretics: According to secondary sources, potassium-sparing diuretics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.PrednisolonePrednisolone: According to clinical observations, psyllium may induce adrenal crisis in patients with adrenal insufficiency; this effect was hypothesized to be caused by inhibited gastrointestinal absorption of prednisolone and/or fludrocortisone caused by psyllium (71). Renally eliminated agentsRenally eliminated agents: According to secondary sources, chewed, crushed, or ground black or blond psyllium may release pigment that is deposited in renal tubules and may be nephrotoxic. A preliminary equivalence study without described randomization and blinding suggested that psyllium lacked a benefit on a biochemical endpoint in individuals with renal failure (96). SalicylatesSalicylates: According to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.SteroidsSteroids: According to clinical observations, psyllium may induce adrenal crisis in patients with adrenal insufficiency; this effect was hypothesized to be caused by inhibited gastrointestinal absorption of prednisolone and/or fludrocortisone caused by psyllium (71). TetracyclinesTetracyclines: According to secondary sources, tetracyclines may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.Psyllium/Herb/Supplement Interactions:
GeneralGeneral: Experts state that soluble fibers may decrease the absorption of drugs (171) and a systematic review on drug interactions with psyllium was published (conclusions lacking) (172). AnalgesicsAnalgesics: According to secondary sources, analgesic agents such as salicylates may have decreased absorption when taken with psyllium. Potentially psyllium may interact with other herbs and supplements with similar effects.AntibacterialsAntibacterials: According to secondary sources, tetracycline antibiotics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. Potentially psyllium may interact with herbs and supplements with similar effects.AntibronchospasticsAntibronchospastics: Wheezing has been reported as allergic manifestations in individuals with repeated psyllium exposures (40; 1; 2; 41). In other clinical research, coughing has been reported (36; 41). Anticoagulants and antiplateletsAnticoagulants and antiplatelets: According to secondary sources, psyllium may reduce the absorption of anticoagulant and antiplatelet agents. However, effects on warfarin levels by coadministered psyllium were lacking in human research (60). Antidepressant agents, tricyclic (TCAs)Antidepressant agents, tricyclic (TCAs): Dietary fiber has been shown to lower the blood levels and effectiveness of tricyclic antidepressant medications in human research (68). Reduced dietary fiber intake increased the blood levels and improved symptoms in these patients. AntidiarrhealsAntidiarrheals: In human research, psyllium increased defecation frequency and stool weight and decreased transit time (102; 38; 115). However, in other human studies, psyllium was shown to have an antidiarrheal effect, which was attributed to its ability to increase the water-holding capacity and viscosity of stools, thereby delaying gastric emptying and improving stool consistency (104; 105; 106; 107). Antigout agentsAntigout agents: According to secondary sources, psyllium may increase the effects of antigout agents.Antihemorrhoidal agentsAntihemorrhoidal agents: In human research, psyllium-containing products reduced the symptoms of hemorrhoids in some (122; 123), but not all (124), studies. AntihistaminesAntihistamines: Rhinitis and wheezing have been reported as allergic manifestations in individuals with repeated psyllium exposures (40; 1; 2; 41). Anti-inflammatory agentsAnti-inflammatory agents: According to a systematic review of clinical trials, psyllium reduced levels of CRP (173). In addition, according to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. AntilipemicsAntilipemics: In human research, psyllium decreased total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and the ratio of LDL to high-density lipoprotein (HDL) (30; 174; 132; 78; 42; 39; 131; 140; 125; 43; 143; 84; 92; 26; 139; 95; 90; 130; 35; 58; 34; 59; 109; 175). With respect to triglyceride (TG) levels (30; 39; 135; 89; 125; 92; 90; 43; 35; 34) and HDL (30; 174; 132; 39; 89; 125; 92; 90; 43; 130; 29), evidence is mixed, with most studies in support of a lack of effect on TG levels and increased, decreased, or no effects on HDL cholesterol. Antineoplastic agentsAntineoplastic agents: In animal research, psyllium has been shown to improve the chemoprotective effect of wheat bran (177). In other animal research, psyllium has been shown to help maintain normal cell proliferation in the colon (178; 179). In human research, psyllium fiber has been shown to be converted to butyrate, which appears to be important in protecting against colon cancer (112). In vitro, fermentation products of the Plantago ovata husk (fermented with colonic bacteria) induced apoptosis of cancer cell lines (180). Contrary to these findings, in patients with colorectal adenoma, there was a significant increase in adenoma recurrence risk in subjects receiving ispaghula husk vs. placebo (98). Antiobesity agentsAntiobesity agents: In the popular press, psyllium has been suggested as a possible weight loss aid; however, conclusive results from clinical trials are lacking (43; 66; 35; 58; 34). In human research, psyllium increased satiety and decreased food intake (155) and increased the postmeal respiratory quotient (156); however, an effect on satiety was lacking in a separate study (156). In a clinical trial, psyllium use resulted in a reduction in the ratio of android fat to gynoid fat (58). AntipsychoticsAntipsychotics: In epidemiological research, concomitant use of Chinese medicine and antipsychotics in schizophrenic patients suggested that Semen Plantaginis in concomitant use with quetiapine, clozapine, and olanzapine was associated with increased risk of adverse outcomes (182). AntipyreticsAntipyretics: According to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.Antiseizure agentsAntiseizure agents: In human research, psyllium decreased the absorption and concentration of carbamazepine (61). If patients are treated with carbamazepine and psyllium, their administration times should be separated as far as possible, and plasma levels of carbamazepine should be monitored. Theoretically, psyllium may interact with herbs and supplements with similar effects.CalciumCalcium: In human research, psyllium (Metamucil?) resulted in slightly reduced absorption of calcium, but statistical significance was lacking (65). In human research, psyllium resulted in decreased plasma levels of calcium (66). Cardiac glycosidesCardiac glycosides: In human research, psyllium reduced the AUC of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin level was lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). Cardiovascular agentsCardiovascular agents: In human research, psyllium reduced the AUC of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin levels was lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). According to secondary sources, potassium-sparing diuretics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions. ChitosanChitosan: In human research, use of psyllium and chitosan together has increased fat excretion in the stool (69). Colonoscopy preparationColonoscopy preparation: In human research, effects of psyllium on tolerability of a standard polyethylene glycol-based lavage preparation for colonoscopy were lacking; however, the efficacy of the bowel preparation was reduced (168). CopperCopper: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64). Dermatologic agentsDermatologic agents: In clinical research, a rash was reported in the psyllium group (36). DigitalisDigitalis: In human research, psyllium reduced the AUC of digoxin, although an effect on height and time of peak serum digoxin or 24-hour urinary digoxin level were lacking (183). In other human research, changes in trough levels of digoxin following psyllium (Vi-Siblin?) use were lacking (184). According to secondary sources, psyllium may interact with digitalis. DiureticsDiuretics: According to secondary sources, potassium-sparing diuretics may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.Gastrointestinal agentsGastrointestinal agents: In human research, psyllium ingestion increased defecation frequency and stool weight, and decreased transit time (102; 38; 115). Experts have suggested that psyllium may have additive effects when taken with laxatives (105; 99; 100; 101; 102; 103) or, based on mechanism of action, antidiarrheals (104; 105; 106; 107). Improvements in symptoms of anorectal fissures have been reported following psyllium administration (185), and results from early clinical research suggested that psyllium reduced the number of surgeries necessary to heal anal fissures (111). Gastrointestinal adverse effects have been commonly reported following use of psyllium (9; 10; 11; 77; 78; 79; 80; 81; 82; 83; 43; 84; 36; 47; 85; 38; 41; 86; 87; 88; 89; 90; 91; 92; 93; 94; 95; 39; 96; 97; 72; 73; 74; 75; 76). HematologicsHematologics: Systemic eosinophilia without other allergic manifestations has been attributed to psyllium-containing bulk laxative therapy in a 60 year-old woman being treated for irritable bowel syndrome (37). Hydrophilic agentsHydrophilic agents: According to secondary sources, psyllium may increase the effects of hydrophilic agents. Psyllium is hydrophilic because of its high content of hemicelluloses (186; 2). HypoglycemicsHypoglycemics: In human research, in the presence or absence of other hypoglycemic agents, psyllium decreased plasma glucose and HbA1C (43; 49; 41; 42; 47; 44; 45; 46; 48; 50; 51; 52; 53; 54; 55; 56); however, acute effects were lacking in some available studies (57). Long-term effects of psyllium on glycemic indices were mixed (35; 34; 58; 59; 56). Also, in human research, psyllium decreased insulin levels (55). According to a systematic review, in combination with antidiabetic agents, psyllium had beneficial effects on blood lipids (35). HypotensivesHypotensives: In human research, psyllium reduced SBP and/or DBP (32; 33; 34; 35). IronIron: In human research, psyllium resulted in slightly reduced plasma levels of iron (66). The effect of dietary fiber on iron absorption in humans has been discussed further (187); however, details are lacking. LaxativesLaxatives: In human research, increased defecation frequency and stool weight and decreased transit time occurred (102; 38; 115). According to secondary sources, experts recommend avoiding other laxatives when taking psyllium, because the laxative effects may be increased. Musculoskeletal agentsMusculoskeletal agents: Back pain was reported in 9% of patients in the psyllium group vs. 0% of patients in the placebo group in a clinical trial (38). Exacerbation of gout occurred in one patient (39). Neurologic agentsNeurologic agents: Recurrence of Tourette's syndrome occurred in one patient (39). MagnesiumMagnesium: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64). Renally eliminated agentsRenally eliminated agents: According to secondary sources, chewed, crushed, or ground black or blond psyllium may release pigment that is deposited in renal tubules and may be nephrotoxic. A preliminary equivalence study without described randomization and blinding suggested that psyllium lacked a benefit on a biochemical endpoint in individuals with renal failure (96). RiboflavinRiboflavin: In human research, psyllium reduced the 24-hour apparent absorption of riboflavin (from 31.8% to 25.4% and 26.1%, p<0.01) (188). SalicylatesSalicylates: According to secondary sources, salicylates may have decreased absorption when taken with psyllium. Administration times should be separated to minimize potential interactions.Vitamin B12Vitamin B12: In human research, ispaghula husk induced changes in levels of vitamin B12 (67). ZincZinc: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64). Psyllium/Food Interactions:
GeneralGeneral: The long-term use of psyllium with meals may reduce nutrient absorption requiring vitamin or mineral supplementation (64). However, the use of blond psyllium husk for up to six months did not clinically alter vitamin or mineral status in a review of eight human trials (77). Soluble fiberSoluble fiber: Psyllium has been used in combination with other types of soluble fiber (e.g., guar gum, pectin, locust bean gum, acacia) in clinical trials (189; 190; 191). Psyllium/Lab Interactions:
Apolipoproteins (apo)Apolipoproteins (apo): In human research, psyllium reduced levels of apo B and the apo B:apo A ratio (35; 109). Appetite hormonesAppetite hormones: In human research, meals enriched with psyllium (23g daily) decreased ghrelin and peptide YY (PYY) responses (55). In human research, psyllium decreased plasma gastric inhibitory peptide (54). Asymmetric dimethylarginine (ADMA)Asymmetric dimethylarginine (ADMA): In human research, changes in ADMA levels were lacking following psyllium use (192). Blood glucose and HbA1CBlood glucose and HbA1C: In human research, in the presence or absence of other hypoglycemic agents, psyllium decreased plasma glucose and HbA1C (43; 49; 41; 42; 47; 44; 45; 46; 48; 50; 51; 52; 53; 54; 55; 56); however, acute effects were lacking in some available studies (57). Long-term effects of psyllium on glycemic indices were mixed (35; 34; 58; 59; 56). Blood pressureBlood pressure: In human research, psyllium reduced SBP and/or DBP (32; 33; 34; 35). CalciumCalcium: In human research, psyllium (Metamucil?) resulted in slightly reduced absorption of calcium, but statistical significance was lacking (65). In human research, psyllium resulted in decreased plasma levels of calcium (66). CopperCopper: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64). C-reactive proteinC-reactive protein: According to a systematic review of clinical trials, psyllium reduced levels of CRP (173). However, in other human research, this effect was lacking (193). Fecal markersFecal markers: In human research, changes in fecal excretion of total bile acid, pH of fecal water, and transit times of carmine were lacking in the psyllium group, and isomers of deoxycholic acid were increased (25). FructosamineFructosamine: In human research, psyllium reduced levels of fructosamine (59). Heart rateHeart rate: In human research, compared with control, psyllium lacked an effect on heart rate (33). HematocritHematocrit: In human research, modifications in hematocrit values were lacking (66). HemoglobinHemoglobin: In human research, modifications in hemoglobin concentration were lacking (66). InsulinInsulin: In human research, psyllium decreased insulin levels (55). IronIron: In human research, psyllium resulted in slightly reduced plasma levels of iron (66). The effect of dietary fiber on iron absorption in humans has been discussed further (187); however, details are lacking. MagnesiumMagnesium: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64). Prothrombin time/international normalized ratio (INR)Prothrombin time/international normalized ratio (INR): According to secondary sources, psyllium may reduce the absorption of anticoagulant and antiplatelet agents. However, effects on warfarin levels by coadministered psyllium were lacking in human research (60). Red blood cell countsRed blood cell counts: In human research, modifications in red blood cell counts were lacking (66). RiboflavinRiboflavin: In human research, psyllium reduced the 24-hour apparent absorption of riboflavin (from 31.8% to 25.4% and 26.1%, p<0.01) (188). Serum lipid profileSerum lipid profile: In human research, psyllium decreased total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and the ratio of LDL to high-density lipoprotein (HDL) (30; 174; 132; 78; 42; 39; 131; 140; 125; 43; 143; 84; 92; 26; 139; 95; 90; 130; 35; 58; 34; 59; 109; 175). With respect to triglyceride (TG) levels (30; 39; 135; 89; 125; 92; 90; 43; 35; 34) and HDL (30; 174; 132; 39; 89; 125; 92; 90; 43; 130; 29), evidence is mixed, with most studies in support of a lack of effect on TG levels and increased, decreased, or no effects on HDL cholesterol. Uric acidUric acid: In human research, psyllium reduced levels of uric acid (59). Vitamin B12Vitamin B12: In human research, ispaghula husk induced changes in levels of vitamin B12 (67). ZincZinc: In human research, hemicellulose has been shown to increase the excretion and reduce the retention of zinc, copper, and magnesium (64).