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The antimicrobial activity of essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium.

The essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium were studied for the first time for their antimicrobial activity against nine organisms. All the essential oils exhibited some broad spectrum antibacterial activity, at a concentration of 80 microg/mL. The essential oils of Hypericum species showed antibacterial activity against the tested organisms and a yeast.

Anti-Infective Agents↗

In vitro cytotoxicity and antitumour properties of Hypericum mysorense and Hypericum patulum.

The methanol extracts of the aerial parts of Hypericum mysorense and Hypericum patulum were tested for in vitro cytotoxicity on HEp-2, RD and Vero cell lines and antitumour activity using DLA and HEp-2 cell lines. The cell viability and morphological changes were assessed. Of these extracts, Hypericum patulum (stem) extract showed strong cytotoxicity against all the cell lines used. The CTC50 of the Hypericum patulum (stem) extract was 1.71 microg/mL for HEp-2, 1.53 microg/mL for RD and 2.23 microg/mL for Vero cell lines. The Hypericum patulum (leaves) and Hypericum mysorense (aerial parts) extracts showed moderate cytotoxicity and Hypericum patulum (aerial parts) extract did not show any cytotoxicity up to 1,000 microg/mL concentration. In the clonogenic assay, no colony formation was observed at a concentration of 300 micro g/mL and above for Hypericum mysorense (aerial parts), 400 microg/mL and above for Hypericum patulum (leaves) and 500 microg/mL and above for Hypericum patulum (stem) extracts. In the short term antitumour studies using DLA cells, 50% viability was observed in the concentration range 100-200 microg/mL for Hypericum patulum (leaves and stem) and 200-400 microg/mL for Hypericum mysorense (aerial) extract. In the long term antitumour activity using the HEp-2 cell line, no colony formation was observed over a concentration of 1.6 microg/mL for the Hypericum patulum (stem) extract.

Animals↗

Antidepressant properties of some Hypericum canariense L. and Hypericum glandulosum Ait. extracts in the forced swimming test in mice.

It has been shown in a previous work that the methanol extract obtained from the aerial part in blossom of Hypericum canariense L. and Hypericum glandulosum Ait. was active in the tetrabenazine and forced swimming test. In the present study, the central nervous effect of the aqueous, butanol and chloroform fractions obtained from the methanol extracts of these Hypericum species was investigated in mice, particularly in animal models of depression. It was found that the immobility time in the forced swimming test was significantly reduced by the butanol and chloroform fraction of both species assayed, producing no effects or only a slight depression on spontaneous motor activity when assessed in a photocell activity meter. In this regard, the efficacy of the chloroform extract from Hypericum glandulosum Ait. (500 mg/kg p.o.) in the forced swimming test was comparable to that of the tricyclic antidepressant imipramine (50 mg/kg p.o.). In addition, the Hypericum glandulosum chloroform fraction was also effective in antagonizing the ptosis induced by tetrabenazine. Moreover, Hypericum canariense butanol fraction and Hypericum glandulosum chloroform fraction produced a slight but significant hypothermia. Taken together, these data demonstrate that the butanol and chloroform fractions from Hypericum canariense and Hypericum glandulosum possess antidepressant-like effects in mice, providing further support for the traditional use of these plants in the Canary Islands folk medicine against central nervous disorders.

Animals↗

Final report on the safety assessment of Hypericum perforatum extract and Hypericum perforatum oil.

Hypericum Perforatum Extract is an extract of the capsules, flowers, leaves, and stem heads of Hypericum perforatum, commonly called St. John's Wort. Hypericum Perforatum Oil is the fixed oil from H. perforatum. Techniques for preparing Hypericum Perforatum Extract include crushing in stabilized olive oil, gentle maceration over a period of weeks, followed by dehydration and filtration. Propylene Glycol and Butylene Glycol extractions were also reported. The following components have variously been reported to be found in H. perforatum: hypericin, naphtodianthrones, flavonoids, terpene and sesquiterpene oils, phenylpropanes, biflavones, tannins, xanthones, phloroglucinols, and essential oils. Hypericum Perforatum Extract is used in over 50 cosmetic formulations and Hypericum Perforatum Oil in just over 10, both across a wide range of product types. Acute toxicity studies using rats, guinea pigs, and mice indicate that the extract is relatively nontoxic. Animals fed H. perforatum flowers for 2 weeks showed significant signs of toxicity, including erythema, edema of the portion of the body exposed to light, alopecia, and changes in blood chemistry. In a chronic study, rats fed H. perforatum gained less weight than control animals. Mixtures containing the extract and the oil were not irritants or sensitizers in animals. Because of the presence of hypericin, H. perforatum is a primary photosensitizer. In clinical tests, a single oral administration of Hypericum extract resulted in hypericin appearing in the blood. With long-term dosing, a steady-state level in blood was reached after 14 days. The polyphenol fraction of H. perforatum had immunostimulating activity, whereas the lipophilic portion had immunosuppressing properties. Mixtures of the extract and the oil produced minimal or no ocular irritation in rabbit eyes. Mutagenic activity in an Ames test was attributed to flavonols in one study and to quercitin in another, but other genotoxicity assays were negative. No carcinogenicity or reproductive and developmental toxicity data were available. A mixture of the extract and the oil was not irritating in clinical studies. Adverse reactions to Hypericum extract in the clinical treatment of depression include skin reddening and itching, dizziness, constipation, fatigue, anxiety, and tiredness. Absent any basis for concluding that data on one member of a botanical ingredient group can be extrapolated to another in a group, or to the same ingredient extracted differently, these data were not considered sufficient to assess the safety of these ingredients. Additional data needs include current concentration of use data; function in cosmetics; photosensitization and phototoxicity data using visible light; gross pathology and histopathology in skin and other major organ systems associated with repeated dermal exposures; dermal reproductive/developmental toxicity data; human skin irritation and sensitization data using the oil; and ocular irritation data, if available. Until these data are available, it is concluded that the available data are insufficient to support the safety of these ingredients in cosmetic formulations.

Administration, Oral↗

Analgesic and topical anti-inflammatory activity of Hypericum canariense L. and Hypericum glandulosum Ait.

The present study investigates the analgesic and topical anti-inflammatory activities of the infusion, methanol extract and fractions of the aerial part in blossom of Hypericum canariense L. and Hypericum glandulosum Ait. in mice. The acetic acid-induced writhing test, tail flick test and the tetradecanoylphorbol acetate (TPA)-induced ear inflammation model in mice were used to determine these effects. Our findings show that oral administration of methanol extracts, and the aqueous, butanol and chloroform fractions of both species and the infusions of Hypericum glandulosum significantly inhibit acetic acid-induced writhing in mice. Only the infusion, methanol extract and butanol and chloroform fractions of Hypericum glandulosum were significantly active in the tail flick assay, suggesting that they may have central analgesic properties. On the other hand, the topical treatment of all extracts tested from both species, with the exception of the infusions and the Hypericum canariense aqueous fraction, significantly reduced the TPA-induced ear oedema. In conclusion, the results indicate analgesic and topical anti-inflammatory activities in mice for the Hypericum species studied.

Acetic Acid↗

Activity of Hypericum brasiliense and Hypericum cordatum on the central nervous system in rodents.

Hydroalcoholic extracts from species Hypericum brasiliense Choisy (HB) and Hypericum cordatum (Vell. Conc.) N. Robson (HC), were evaluated on the central nervous system (CNS) in some pharmacological tests. Signs of toxicity were observed for both species during the initial screening when high doses of up to 100 mg/kg (i.p.) and 1000 mg/kg (oral) were utilized. HC presented greater toxicity, with LD(50) of 269 mg/kg, as compared to HB (537 mg/kg). Alterations in sleeping time and in motor coordination were not observed both for HB and for HC. On the other hand, both species showed signs of general depressant action on the CNS, verified by decreased motor activity. Furthermore, animals treated with HB presented an increase in response time to thermal stimulus with doses of 50 mg/kg (i.p.) and 500 mg/kg (oral) suggesting possible analgesic action. Both HB and HC were tested in animal models to verify antidepressant action (forced swimming and hypothermy induced by apomorphine). In these tests, neither of the plants inhibited hypothermy, nor did they reduce immobility time in forced swimming.

Administration, Oral↗

In vitro pollen germination in Hypericum perforatum L. and Hypericum rumeliacum Boiss.

In vitro pollen germination and pollen tube growth investigations are valuable tools used in identification of the effects of environmental factors and genotypic differences on pollen viability, pollen germination and tube elongation. In this study pollen viability, in vitro pollen germination capacity, abnormality ratios and tube length in germinated pollens of Hypericum perforatum L. and H. rumeliacum Boiss. were investigated. Both of these species has spheroid-shaped and tricolporate pollen grains. The diameters of Hypericum perforatum and H. rumeliacum pollens were found as 24 +/- 3 microm and 19 +/- 2 microm, respectively. Pollen viability of H. perforatum and H. rumeliacum was found as 83% and 72%, respectively. The germination percentages were found as 12.85% for H. perforatum and 64.42% for H. rumeliacurm. Tube lengths in germinated pollens of both taxa were measured approximately as 95.25 +/- 38 microm in H. perforatum and 165.92 +/- 53 microm in H. rumeliacium 4 h after inoculation. In germinated pollen grains of H. perlbratum and H. rumeliacumn abnormality percentages were determined as 13.23% and 43.97%, respectively. In germinated pollens of these two species, highly significant (P < 0.00001) differences in in vitro germination percents and abnormality percents were observed. Abnormalities such as swollen tube tip, branched tube, spiralled tube and excessive tube formation were observed in pollen tubes. The results of this study showed that there were obvious differences in pollen germinability between these two species growing under the same environmental conditions.

Environment↗

Hypericum extract in patients with MDD and reversed vegetative signs: re-analysis from data of a double-blind, randomized trial of hypericum extract, fluoxetine, and placebo.

Hypericum extract (HE) might be favourably active in depressed patients with reversed vegetative signs (RVS). Therefore, we performed an exploratory subgroup analysis of a three-armed study to compare HE, fluoxetine, and placebo in patients with major depressive disorder (MDD) in a 12 wk trial. A total of 135 patients were randomized to 12 wk treatment with HE LI 160 (900 mg/d), fluoxetine (20 mg/d), or placebo. Patients with RVS were defined in two steps, according to DSM-IV. First, patients with melancholy-related vegetative signs were excluded. Secondly, patients had to have at least one score of 2 for the items 22-26 of the HAMD-28 scale, which are related to hypersomnia and hyperphagia. Twenty-seven patients remained in the group. Analysis of covariance (ANCOVA) was applied using the HAMD-17 score. Secondly a chi2 test for response was performed, using the same and further an adapted criterium as in recently published studies. ANCOVA revealed a trend to a global difference. Post-hoc analysis showed a trend to superiority of HE compared to placebo and to fluoxetine, but a very large effect size for both differences. Fluoxetine was not different from placebo. The adapted response criterium showed a significant global difference as well as a significant superiority of HE over placebo and over fluoxetine. These data are based on a small sample size and must be considered tentative. A characterization of vegetative features of patients with depression could lead to an overall increased effect size in the treatment with HE.

Analysis of Variance↗

Hypericum perforatum subspecies angustifolium shows a protective activity on the consequences of unavoidable stress exposure at lower doses than Hypericum perforatum perforatum.

Clinical studies have demonstrated that the antidepressant efficacy of Hypericum perforatum extract is comparable to that of classic antidepressants, such as imipramine. The role played by its components, particularly hypericin and hyperforin, has been examined in different experimental models of depression. The present study was carried out in order to verify the hypothesis that hyperforin is the main active antidepressant component. For this purpose we evaluated the activity of a dry extract from a subspecies of H. perforatum, H. perforatum spp. angustifolium, which has a higher hyperforin content than H. perforatum perforatum, in a series of experimental models of depression. The models used are based on the development of hyporeactivity to aversive stimuli induced by unavoidable stress exposure in rats. The extract of H. perforatum angustifolium presented an efficacy that was similar to that obtained with a treatment with imipramine or H. perforatum perforatum. Furthermore, in the models used the H. perforatum angustifolium extract was active at doses eight times lower than those necessary to produce a comparable activity with H. perforatum extract.

Animals↗

Antinociceptive activity of Hypericum caprifoliatum and Hypericum polyanthemum (Guttiferae).

The aim of the present study was to assess the analgesic activity of the aerial parts of two Hypericum species native to Southern Brazil, H. caprifoliatum and H. polyanthemum. The antinociceptive effect of the H. polyanthemum cyclohexane extract (POL; 180 mg/kg) and of the H. caprifoliatum methanol (MET) and cyclohexane (CH) extracts (90 mg/kg) was evaluated in the hot-plate (ip and po) and writhing (po) tests using male Swiss CF1 mice weighing 22-27 g (N = 10 per group). All extracts displayed antinociceptive effects in the hot-plate test (MET ip = 48%, MET po = 39%, CH ip = 27%, CH po = 50%, POL ip = 74%, and POL po = 49% compared to control). Pretreatment with naloxone (2.5 mg/kg, sc) abolished the effects of CH and POL, and partially prevented the analgesia induced by MET administered by the ip (but not by the po) route. POL and CH (po) significantly reduced the number of writhes induced by acetic acid, while MET was ineffective in this regard. We conclude that the antinociceptive effects of the H. caprifoliatum (CH) and H. polyanthemum (POL) hexane extracts seem to be mediated by the opioid system. Moreover, the antinociceptive activity of the H. caprifoliatum MET extract seems to depend on at least two chemical substances (or groups of substances) with distinct pharmacokinetic profiles and mechanisms of action. Only the naloxone-insensitive component of MET activity showed good bioavailability following oral administration.

Analgesics↗

Comparative efficacy and safety of a once-daily dosage of hypericum extract STW3-VI and citalopram in patients with moderate depression: a double-blind, randomised, multicentre, placebo-controlled study.

OBJECTIVE: The objective of this double-blind, randomised, placebo-controlled, multicentre clinical study was to demonstrate the non-inferiority and safety of the hypericum extract STW3-VI in a once-daily dosage regime in the treatment of moderate depression. During the 6-week treatment phase, the course of depression was documented by use of HAMD (items 1-17), the von Zerssen's Adjective Mood Scale (BfS) and the CGI scales. The primary objective of this 3-arm design study was to demonstrate the non-inferiority of hypericum extract STW3-VI (900 mg) to the SSRI citalopram (20 mg) and superiority of hypericum over placebo. METHODS: Outpatients (N = 388) suffering from moderate depression were enrolled. The safety and tolerability of hypericum extract in comparison to citalopram and placebo was investigated on the basis of CGI, the occurrence of adverse events and the investigation of laboratory parameters and vital signs. RESULTS: From almost identical baseline values of 21.9 +/- 1.2 points (hypericum extract), 21.8 +/- 1.2 points (citalopram) and 22.0 +/- 1.2 points (placebo), the HAMD score was reduced to 10.3 +/- 6.4 (hypericum extract), 10.3 +/- 6.4 (citalopram) and 13.0 +/- 6.9 (placebo), respectively. Based on this data, the statistical significant therapeutic equivalence of hypericum extract STW3-VI to citalopram (p < 0.0001) and the superiority of this hypericum extract over placebo (p < 0.0001) was demonstrated. At the end of treatment 54.2 % (hypericum extract), 55.9 % (citalopram) and 39.2 % (placebo) of the patients were assessed as therapy responders. The secondary efficacy parameters, change in BfS, CGI and amount of therapy responders showed that the hypericum group was not statistically different from the citalopram group, and significantly superior to the placebo group. Significantly more adverse events with "certain", "probable" or "possible" relation to study medication were documented in the citalopram group (hypericum: 17.2 %, citalopram: 53.2 %, placebo: 30 %). In most cases, the investigators assessed the tolerability of hypericum extract, citalopram and placebo as "good" or "very good". CONCLUSION: The non-inferiority of hypericum extract as compared to citalopram and the superiority of both active compounds to placebo were demonstrated, as well as a better safety and tolerability of hypericum extract in comparison to citalopram. These results revealed that hypericum extract STW3-VI is a good alternative to chemically defined antidepressants in the treatment of outpatients with moderate depression.

Adult↗

Efficacy and tolerability of hypericum extract STW3 in long-term treatment with a once-daily dosage in comparison with sertraline.

OBJECTIVE: The objective of this double-blind, multi-center clinical study was to demonstrate the non-inferiority of hypericum extract versus sertraline in the treatment of moderate depression. METHODS: A total of 241 patients with a diagnosis of moderate depressive disorder (according to ICD-10 criteria) were randomized with either 50 mg sertraline or 612 mg hypericum extract (hypericum group n = 123; sertraline group n = 118). According to the study protocol, 200 patients were treated for at least 12 weeks ( n = 102 hypericum extract; n = 98 sertraline); 81 patients in the hypericum group and 80 in the sertraline group were treated after week 12 for an additional 12 weeks. Thus, most patients were treated for a period of 6 months. The primary efficacy variable was the 17-item HAMD total score at the end of the first 12-week double-blind treatment period. RESULTS: After the first 12-week treatment period, the HAMD score decreased from almost identical initial values (22.0 +/- 1.1 for hypericum and 22.1 +/- 1.1 points for sertraline) to 8.3 +/- 5.5 points (hypericum) and 8.1 +/- 5.6 points (sertraline) (mean +/- SD) in the patients treated per-protocol (PP) population. The statistical test for non-inferiority (boundary delta = 3) revealed that hypericum extract is not inferior to sertraline ( P < 0.0001). The mean difference between the treatments was 0.1995 points, with a corresponding one-sided 97.5 % confidence interval (-infinity, 1.3772). In patients who continued treatment in the follow-up phase, the HAMD score at the end of the study was 5.7 +/- 4.8 points (hypericum group) and 7.1 +/- 6.3 points (sertraline group). Comparable improvement was also found for the von Zerssen's Adjective Mood Scale (BfS) and CGI during the first and second 12-week treatment period in both treatment groups. With 68.6 % of patients in the hypericum group and 70.4 % in the sertraline group, the percentage of patients rated as responders did not differ significantly between treatment groups (12 weeks). The adverse events of 12 patients in the hypericum group (9.8 %) and of 16 patients in the sertraline group (13.6 %) were possibly related to study medication. No basic differences in the treatment groups were observed and no interaction with concomitant medication was documented. In most cases , the investigators assessed the tolerability of hypericum extract and sertraline as "good" or "very good." CONCLUSIONS: The results indicate that hypericum extract STW 3 is not inferior to sertraline and that it is a well-tolerated drug for the treatment of moderate depression. These favorable effects were achieved with a once-daily dose of 612 mg of hypericum extract given for up to 24 weeks.

Adolescent↗

The effect of shade, shearing and wool type in the protection of Merino sheep from Hypericum perforatum (St John's wort) poisoning.

OBJECTIVE: To investigate the roles of shade, fleece length and wool type in the protection of sheep from Hypericum perforatum poisoning. ANIMALS: Adult Merino ewes of superfine, fine and medium wool type. DESIGN: Seventy sheep were divided into seven equal groups. During late spring and summer a series of successive, replicate experiments was conducted, each using one group and lasting 5 days. The sheep carried 14 to 24 weeks wool growth. In each experiment the treatments tested were Hypericum +, sunlight + (n = 7); Hypericum +, sun - (n = 1); Hypericum -, sun + (n = 1); Hypericum -, sun - (n = 1). Next, 24 sheep in two equal groups were used in experiments of similar design to the above. Each group consisted of nine recently (1 to 3 weeks previously) shorn and three wool covered (25 to 26 weeks growth) sheep. The treatments tested were Hypericum +, sunlight +, fleece - (n = 9); Hypericum +, sun -, fleece + (n = 1); Hypericum -, sun +, fleece + (n = 1); Hypericum -, sun -, fleece + (n = 1). PROCEDURES: Finely milled Hypericum was administered by gavage to provide 3 mg hypericin / kg body weight. Sheep were sheltered from direct sunlight or were exposed for 5 h per day for 4 successive post-treatment days. Rectal temperatures were measured immediately before and at the end of each sunlight exposure session. Rectal temperature above 40 degrees C was considered indicative of hypericin poisoning. RESULTS: After Hypericum treatment hypericin poisoning was displayed by 26.5% of woolled sheep that were exposed to sunlight, but by none of those that were fully shaded. In similarly treated but recently shorn sheep 94% displayed hypericin poisoning when exposed to sunlight. In the wool covered group the percentages of poisoned animals based on wool type were: superfine 14%, fine 28.5%, medium 33.3%. In the recently shorn group the percentage for all three approached 100%. CONCLUSIONS: A majority of Merinos with at least 14 weeks wool growth will not be poisoned by a single oral dose of 3 mg hypericin /kg, but because hypericin persists in the blood circulation for several days this safe dose will be lowered by continuous daily ingestion. Sheep with access to substantial areas of shade could safely ingest much greater amounts of hypericin. Wool removal greatly increases the risk of poisoning. Superfine Merinos with a wool cover should be able to ingest more hypericin than comparable, medium wool types, without any increased risk of poisoning. The ability of ruminant livestock to safely ingest Hypericum is probably determined more by the amount of skin protection they have against incident sunlight than by differences in hypericin metabolism and excretion capacity.

Administration, Oral↗

Effects of Hypericum perforatum (St. John's wort) on passive avoidance in the rat: evaluation of potential neurochemical mechanisms underlying its antidepressant activity.

Along with traditional pharmacotherapies, extracts of Hypericum perforatum L. (St. John's wort) are used in the treatment of mild to moderately severe depression. Hypericum is a nonspecific inhibitor of the neuronal uptake of monoamines (serotonin, 5-HT; noradrenaline, NA; dopamine, DA) as well as GABA and glutamate. Hypericum extracts have been shown to be active in several different "animal models for antidepressant drugs". As one of a large number of chemical constituents, the phoroglucinol derivative hyperforin might be an important "antidepressant component" of hypericum. However, the exact role of neurochemical mechanisms underlying in vivo actions of hypericum and hyperforin are not well defined. In the present study, we compared the effects of hypericum, hyperforin and hyperforin-free hypericum and the three conventional antidepressants paroxetine, imipramine and desipramine using the passive avoidance (PA) task in the rat. The 5-HT-releasing compound p-chloroamphetamine (PCA), which operates through the 5-HT neuronal transporter, was used to reveal the potential in vivo effects on 5-HT uptake mechanisms. To examine the ability of the test-compounds to enhance noradrenaline (NA) transmission in vivo, subeffective doses of scopolamine were used. Taken together, our results suggest that (1) hypericum given at high doses can probably affect the neuronal 5-HT uptake mechanisms in a manner more reminiscent of TCAs than SSRIs; (2) similar to TCAs and SSRIs, hypericum and hyperforin are active in the scopolamine test. Hyperforin appears to play a major role in the action of hypericum in this model. Both 5-HT and NA might concomitantly contribute to the effects of different antidepressants in the "low-dose scopolamine" model; (3) hypericum might enhance both 5-HT and NA transmission in forebrain limbic brain circuits important for mood control, which could underly its antidepressant effects. However, the relative contribution of different constituents and exact mechanisms of action require further evaluation.

Animals↗

Effect of topical application of Hypericum perforatum extract (St. John's wort) on skin sensitivity to solar simulated radiation.

St. John's wort (Hypericum perforatum) is a tradional folk remedy that is used for the topical treatment of superficial wounds, scars and burns. A characteristic metabolite of St. John's wort is the photodynamic active plant pigment hypericin. It is known that hypericin may cause a severe photodermatitis called hypericism when higher amounts of St. John's wort are ingested orally. To date, no reports on the photosensitizing capacity of topical application of St. John's wort are available. Here, we investigated the effects of Hypericum oil (hypericin 110 microg/mL) and Hypericum ointment (hypericin 30 microg/mL) on skin sensitivity to solar simulated radiation. Sixteen volunteers of the skin types II and III were tested on their volar forearms with solar simulated radiation for photosensitizing effects of Hypericum oil (n=8) and Hypericum ointment (n=8). The minimal erythema dose (MED) was determined by visual assessment, and skin erythema was evaluated photometrically. With the visual erythema score, no change of the MED could be detected after application of either Hypericum oil or Hypericum ointment (P>0.05). With the more sensitive photometric measurement, an increase of the erythema-index after treatment with the Hypericum oil could be detected (P< or =0.01). The results do not provide evidence for a severe phototoxic potential of Hypericum oil and Hypericum ointment, detectable by the clinically relevant visual erythema score. However, the trend towards increased photosensitivity detected with the more sensitive photometric measurement could become relevant in fair-skinned individuals, in diseased skin or after extended solar irradiation.

Administration, Cutaneous↗

The effect of hypericum extract on cardiac conduction as seen in the electrocardiogram compared to that of imipramine.

The electrocardiographic effects of high-dose hypericum extract were compared to the effects of imipramine hydrochloride on ECG recordings in a randomized, double-blind, multicenter treatment study of 209 patients suffering from depression. ECGs were recorded before and after a six-week treatment period with either hypericum extract or imipramine. At the end of the study ECGs of 84 patients treated with hypericum extract and 76 patients treated with imipramine were suitable for an analysis of conduction intervals and pathological findings. In the first ECG analysis comparing high dose hypericum extract with imipramine, a prolongation of the conduction intervals PR, QRS and QTc was found for imipramine. In contrast, a small acceleration of conduction was seen for the high-dose hypericum extract. The comparison of ECGs at the beginning and after six weeks of treatment showed a significant increase in first degree AV-blocks and abnormalities of repolarization under imipramine but a significant reduction of such pathological findings under treatment with hypericum extract. It should be emphasized that this favorable feature of safe cardiac activity was achieved with 1800 mg of hypericum extract. The reduction in pathological ECG features after treatment with hypericum extract may have resulted mainly from the change of medication, probably tricyclics, to hypericum extract. Our results indicate that for the treatment of patients with a pre-existing conductive dysfunction or elderly patients, high-dose hypericum extract is safer with regard to cardiac function than tricyclic antidepressants.

Adult↗

Decreased plasma levels of amitriptyline and its metabolites on comedication with an extract from St. John's wort ( Hypericum perforatum ).

Extracts of St. John's wort ( Hypericum perforatum ) became increasingly popular as easily available remedies for mild to moderate depression. Comedication with hypericum extract was recently shown to drastically reduce plasma concentration of ciclosporin, digoxin, and indinavir. We investigated the possible interaction of hypericum extract LI160 with amitriptyline. Both antidepressants have a high probability of concomitant use. Twelve patients requiring amitriptyline treatment received a single dose of hypericum extract (900 mg) at day 1, continued by a 12-to 14-day treatment with retarded amitriptyline (75 mg twice daily). Then hypericum (900 mg/day) was added for another 14 to 16 days. Steady-state pharmacokinetics of amitriptyline were compared before and after multiple-dose treatment with hypericum extract. Furthermore, comparisons were made for single-dose kinetics of hypericum-extract ingredients hypericin, pseudohypericin, and hyperforin between the first day of concomitant treatment and LI160 alone. Multiple-dose comedication with LI160 led to a statistically significant decrease in the area under the plasma concentration-time curve within one dosing interval of amitriptyline by 22% ( p = 0.03) and nortriptyline by 41% ( p = 0.002), as well as of all hydroxylated metabolites, except for 10-E-hydroxynortriptyline. Plasma levels of amitriptyline and hydroxylated metabolites gradually decreased, whereas nortriptyline concentrations were already markedly decreased after 3 days of cotreatment with hypericum. Cumulative urinary amounts of amitriptyline and metabolites decreased to the same extent as plasma concentrations upon hypericum comedication. Induction of cytochrome P-450 enzymes or drug transporters (P-glycoprotein) by St. John's wort extract may explain this pharmacokinetic interaction. Physicians should be aware of this interaction when treating patients with amitriptyline.

Adult↗