Hydroxycitric acid

HCA/Drug Interactions:

  • Antiarrhythmic agentsAntiarrhythmic agents: Based on anecdotal evidence, the potential drug interactions of Garcinia cambogia, containing high levels of HCA, include interference with antiarrhythmics, nitrates, and calcium-channel blockers, antagonism of beta-adrenoreceptor-blocking drugs, potentiation of cardiac glycosides, and risk of arrhythmia when combined with depolarizing muscle relaxants or terfenadine.
  • AntibioticsAntibiotics: Based on in vitro study, crude extracts of the leaves, fruits, roots, stem, and trunk bark of Garcinia atroviridis, containing high levels of HCA, exhibited broad-spectrum antibacterial effects to both Gram-positive (B. subtilis B28 & B29, MRSA, S. aureus) and Gram-negative bacteria (E. coli and P. aeruginosa) (17). Theoretically, concurrent use of HCA with antibiotics may have additive effects.
  • Anticoagulants and antiplateletsAnticoagulants and antiplatelets: Based on human study, HCA may decrease acetyl-CoA content in platelet cytoplasm and suppress malonyl dialdehyde (MDA) synthesis and platelet aggregation (11). Theoretically, concurrent use of HCA and anticoagulants or antiplatelets may increase the risk of bleeding.
  • Antidiabetic agentsAntidiabetic agents: Based on clinical studies, metformin, an oral drug used for the treatment of type 2 diabetes that inhibits gluconeogenesis, may be used as an adjunct to HCA and carnitine for the treatment of obesity (18). This combination has also been found to potentiate the appetite-suppressant and thermogenic benefits of HCA/carnitine therapy. In diabetic mice, HCA reduced insulin resistance and lowered fasting plasma insulin and glucose (12). In in vivo rat studies, HCA decreased absorption of glucose in small intestinal tissue and improved glucose tolerance (19; 20). Theoretically, concurrent use of HCA and antidiabetic agents may increase the risk of hypoglycemia.
  • AntifungalsAntifungals: Based on in vitro study, crude extracts of Garcinia atroviridis, containing high levels of HCA, showed significant antifungal activity against Cladosporium herbarum (MID: 100mcg) and its leaf (MID: 400mcg) extracts (17). Theoretically, concurrent use of HCA and antifungal agents may have additive effects.
  • Anti-inflammatory agentsAnti-inflammatory agents: Based on animal study, HCA reduced inflammatory markers, including C-reactive protein (CRP) and IL-6 cytokine levels (12). Theoretically, concurrent use of HCA and anti-inflammatory agents may have additive effects.
  • Antilipemic agentsAntilipemic agents: Based on case reports, an incident of rhabdomyolysis has been reported in a patient taking a weight loss herbal medicine which contained 50% HCA (10). Theoretically, concurrent use of HCA and antilipemic agents may increase the risk of adverse effects, including rhabdomyolysis.
  • AntineoplasticsAntineoplastics: Based on in vitro study, crude extracts of the leaves, fruits, roots, stem, and trunk bark of Garcinia atroviridis, containing high levels of HCA, showed antitumor activities (17). Theoretically, concurrent use of HCA and antineoplastic agents may have additive effects.
  • BronchodilatorsBronchodilators: Based on human study, peak expiratory flow rate (PEFR) may be increased following administration of Garcinia kola, which contains high level of HCA (21). Theoretically, concurrent use of HCA and bronchodilators may have additive effects.
  • Exercise performance enhancersExercise performance enhancers: Based on human studies, HCA decreased the respiratory exchange ratio and blood free fatty acid concentrations in untrained men doing intense exercise (3) and increased fat metabolism and oxidation in untrained women and athletes (5; 4). An animal study also showed that chronic administration of HCA promoted lipid oxidation and spared carbohydrate utilization in mice at rest and during running (22). Theoretically, concurrent use of HCA and exercise performance enhancers may have additive effects.
  • Weight loss agentsWeight loss agents: Based on animal studies, HCA may promote weight loss through a suppression of appetite (19; 23; 20); decreases in energy conversion ratio, respiratory quotient (RQ) and energy expenditure (EE) in rats (23; 20); increases in serotonin availability; increases in fat oxidation; and reductions in cholesterol, LDL, triglycerides, and leptin in both humans and rats (24; 2; 7; 13; 25; 26; 27; 28). Theoretically, concurrent use of HCA and weight loss agents may have additive effects.

    • HCA/Herb/Supplement Interactions:

  • AntiarrhythmicsAntiarrhythmics: Based on anecdotal evidence, the potential drug interactions of Garcinia cambogia, containing high levels of HCA, include interference with antiarrhythmics, nitrates, and calcium-channel blockers, antagonism of beta-adrenoreceptor-blocking drugs, potentiation of cardiac glycosides, and risk of arrhythmia when combined with depolarizing muscle relaxants or terfenadine.
  • AntibacterialsAntibacterials: Based on in vitro study, crude extracts of the leaves, fruits, roots, stem, and trunk bark of Garcinia atroviridis, containing high levels of HCA, exhibited broad-spectrum antibacterial effects to both Gram-positive (B. subtilis B28 & B29, MRSA, S. aureus) and Gram-negative bacteria (E. coli and P. aeruginosa) (17). Theoretically, concurrent use of HCA with antibacterial agents may have additive effects.
  • Anticoagulants and antiplateletsAnticoagulants and antiplatelets: Based on human study, HCA may decrease acetyl-CoA content in platelet cytoplasm and suppress malonyl dialdehyde (MDA) synthesis and platelet aggregation in diabetic patients (11). Theoretically, concurrent use of HCA and anticoagulants or antiplatelets may increase the risk of bleeding.
  • AntifungalsAntifungals: Based on in vitro study, crude extracts of Garcinia atroviridis, containing high levels of HCA, showed significant antifungal activity against Cladosporium herbarum (MID: 100mcg) and its leaf (MID: 400mcg) extracts (17). Theoretically, concurrent use of HCA and antifungal agents may have additive effects.
  • Anti-inflammatory herbsAnti-inflammatory herbs: Based on animal study, HCA reduced inflammatory markers, including C-reactive protein (CRP) and IL-6 cytokine levels (12). Theoretically, concurrent use of HCA and anti-inflammatory agents may have additive effects.
  • AntilipemicsAntilipemics: Based on case reports, an incident of rhabdomyolysis has been reported in a patient taking a weight loss herbal medicine which contained 50% HCA (10). Theoretically, concurrent use of HCA and antilipemic agents may increase the risk of adverse effects, including rhabdomyolysis.
  • AntineoplasticsAntineoplastics: Based on in vitro study, crude extracts of the leaves, fruits, roots, stem, and trunk bark of Garcinia atroviridis, containing high levels of HCA, showed antitumor activities (17). Theoretically, concurrent use of HCA and antineoplastic agents may have additive effects.
  • AntioxidantsAntioxidants: Based on animal study, HCA may reduce oxidative stress (12; 17). Theoretically, concurrent use of HCA and antioxidants may have additive effects.
  • BronchodilatorsBronchodilators: Based on human study, peak expiratory flow rate (PEFR) may be increased following administration of Garcinia kola, which contains high level of HCA (21). Theoretically, concurrent use of HCA and bronchodilators may have additive effects.
  • Exercise performance enhancersExercise performance enhancers: Based on human studies, HCA decreased the respiratory exchange ratio and blood free fatty acid concentrations in untrained men doing intense exercise (3) and increased fat metabolism and oxidation in untrained women and athletes (5; 4). An animal study also showed that chronic administration of HCA promoted lipid oxidation and spared carbohydrate utilization in mice at rest and during running (22). Theoretically, concurrent use of HCA and exercise performance enhancers may have additive effects.
  • Gymnema sylvestreGymnema sylvestre: The combination of HCA-SX with Gymnema sylvestre has been shown in one clinical trial to have weight loss effects (2).
  • HypoglycemicsHypoglycemics: Based on clinical studies, metformin, an oral drug (originated from goat's rue or French lilac) used for the treatment of type 2 diabetes that inhibits gluconeogenesis, may be used as an adjunct to HCA and carnitine for the treatment of obesity (18). This combination has also been found to potentiate the appetite-suppressant and thermogenic benefits of HCA/carnitine therapy. In diabetic mice, HCA reduced insulin resistance and lowered fasting plasma insulin and glucose (12). In in vivo rat studies, HCA decreased absorption of glucose in small intestinal tissue and improved glucose tolerance (19; 20). Theoretically, concurrent use of HCA and blood sugar-lowering agents may increase the risk of hypoglycemia.
  • Niacin-bound chromiumNiacin-bound chromium: The combination of HCA-SX with niacin-bound chromium has been reported in one clinical trial to have weight loss effects (2).
  • Weight loss herbs and supplementsWeight loss herbs and supplements: Based on animal studies, HCA may promote weight loss through a suppression of appetite (19; 23; 20); decreases in energy conversion ratio, respiratory quotient (RQ) and energy expenditure (EE) in rats (23; 20); increases in serotonin availability; increases in fat oxidation; and reductions in cholesterol, LDL, triglycerides, and leptin in both humans and rats (24; 2; 29; 13; 25; 26; 27; 28). Theoretically, concurrent use of HCA and weight loss agents may have additive effects.

    • HCA/Food Interactions:

  • Lipogenic dietLipogenic diet: HCA was shown to be a potent inhibitor of ATP citrate-lyase, which catalyzes the extramitochondrial cleavage of citrate to oxaloacetate and acetyl-CoA. The inhibition of this reaction limits the availability of acetyl-CoA units required for fatty acid synthesis and lipogenesis during a lipogenic diet. Review of extensive animal studies indicated that HCA suppresses fatty acid synthesis, lipogenesis, and food intake (1). HCA has been suggested to increase fat metabolism, which may be associated with a decrease in glycogen utilization during exercise (4).

    • HCA/Lab Interactions:

  • Creatine kinaseCreatine kinase: A 54 year-old woman ingested a weight loss herbal medicine containing high levels of HCA and showed an increase of serum creatine kinase (10). The active ingredients of the herbal medicine were ma huang, guarana, chitosan, Gymnema sylvestre, Garcinia cambogia (containing high levels of HCA), and chromium. The elevation of creatine kinase suggests that muscle breakdown may be one of the mechanisms of weight loss with this preparation.
  • Platelet aggregationPlatelet aggregation: HCA decreased acetyl-CoA content in platelet cytoplasm along with suppression of malonyl dialdehyde (MDA) synthesis and platelet aggregation in diabetic patients (11).