Clinical and Pharmacological Studies

Studies on this site refer to scientific studies. These will be continually added to over the years as herbal medicine gains increased interest in the scientific world. While many of the studies are carried out using the whole herb others use only specific constituents considered to be the most active. All are useful to herbalists as they validate the use of specific herbs and enable us to consider new options or combinations.

Clinical Studies


  • Improvement of acne with Vitex
  • Treatment of acne with Vitex
  • Vitex for acne vulgaris, indurata, conglobata and follicularis
  • Vitex treatment improves acne

Anantibiotic properties

  • Sarsaparilla has antibiotic properties

Antioxidant activity

  • Dioscorea and DHEA possess antioxidant properties



  • Zizyphus combination for anxiety
  • Zizyphus combination is anxiolytic


Breast milk production


  • Vitex effective as a galactogogue
  • Vitex increases breast milk production

Bronchial Effects


  • Bronchoconstriction countered by forskolin
  • Forskolin counters bronchoconstriction
  • Inhalation of oils beneficial for chronic bronchitis


  • Filipendula for treatment and prevention of uterine cervical cancer


Cardiovascular disorders


  • Angelica sinensis for Buerger’s disease and constrictive aortitis
  • Coleus may be of benefit in cardiomyopathy
  • Dioscorea nipponica beneficial for coronary disease
  • Effects of Angelica sinensis on pulmonary hypertension
  • Green tea protective against coronary atherosclerosis
  • Prevention of cardiovascular disease with meadowsweet and hawthorn
  • Stevioside for treatment of hypertension
  • Treatment of cerebral arteriosclerosis with saponins from Dioscorea caucasia
  • Treatment of essential arterial hypertension with Olea europaea


Colds & flus


  • Andrographis effective in treatment of the common cold
  • Echinacea reduces cold & flu symptoms and duration
  • Echinacea, Baptisia and Thuja effective against the common cold
  • Treatment of upper-respiratory tract infections with Andrographis


  • Chronic colitis treated with Taraxacum, Hypericum, Melissa, Calendula and Foeniculum



  • Comparison of St John’s wort and imipramine
  • Depression in alcoholics
  • Hypericum: depression, anxiety and agitation


  • Treatment of children’s diarrhoea with chamomile and pectin


  • Adhatoda application for gingivitis



  • Topical forskolin for glaucoma
  • Topical forskolin lowers intra-ocular pressure
  • Treatment of glaucoma with coleus


Glucose tolerance

  • Stevia increases glucose tolerance


  • Reduce pain and inflammation



  • Hepatitis B and C: Minor Bupleurum formulation
  • Treatment of liver disorders with Angelica sinensis
  • Treatment of viral hepatitis with picrorrhiza
  • Zizyphus reduces high serum transaminase levels

Herpes infections

  • Reduced frequency and severity

HIV positive

  • Effects of andrographolide on HIV-induced cell cycle dysregulation


  • Low progesterone levels increased with Vitex
  • Multiple follicular development associated with Vitex
  • Treatment of infertility with Angelica sinensis
  • Vitex restores progesterone levels and prolongs elevation of BBT in luteal phase


  • Interaction of Hypericum perforatum with cyclosporin A metabolism

Latent hyperprolactinaemia / Prolactin secretion

  • Effects of Vitex on prolactin level dependent on dose and on initial prolactin level
  • Elevated prolactin levels lowered with Vitex
  • Paeonia and Glycyrrhiza for hyperprolactinaemia
  • Prolactin levels normalised with Vitex


  • Treatment of leprosy with sarsaparilla


  • Treatment of mastalgia with Vitex


  • Black cohosh for menopausal symptoms
  • Effects of isoflavone extract on hot flushes
  • Hypericum perforatum & Cimicifuga racemosa combination
  • Isoflavones from red clover leaf improve systemic arterial compliance but not plasma lipids
  • Isoflavones may help relieve menopausal symptoms
  • Reduction in menopausal symptoms, comparisons with oestrogen
  • Reduction in sweating, insomnia and hot flushes
  • Reduction of menopausal symptoms, depression & anxiety

Menstrual irregularities

  • Paeonia and Glycyrrhiza (TJ-68) helps infertility, oligomenorrhoea and excess androgen
  • Paeonia and Glycyrrhiza for polycystic ovarian disease
  • Treatment of corpus luteum insufficiency with Vitex
  • Treatment of dysmenorrhoea with herbal formula
  • Treatment of menorrhagia and polymenorrhoea with Vitex
  • Treatment of menstrual disorders with Vitex.
  • Treatment of polycystic ovarian syndrome with Paeonia and Glycyrrhiza
  • Vitex for amenorrhoea, oligomenorrhoea and cystic hyperplasia
  • Vitex for menstrual time anomalies, PMS, infertility and multiple diagnosis
  • Vitex for polymenorrhoea, oligomenorrhoea and menorrhagia


  • Prevention of miscarriage with Chamaelirium luteum

Obsessive-compulsive disorder

  • Treatment of OCD with hypericin


  • Diacerein treatment for osteoarthritis
  • Osteoarthritis treatment assisted with inclusion of diacerein

Premenstrual syndrome

  • Premenstrual epilepsy treated with Vitex
  • Premenstrual herpes simplex treated with Vitex
  • Premenstrual mouth ulcers treated with Vitex
  • Treatment of PMS, corpus luteum insufficiency and fibroids with Vitex
  • Trial on Vitex for PMS
  • Vitex agnus castus effective in the treatment of PMS
  • Vitex for PMS and related menstrual disorders
  • Vitex for PMS including breast tenderness, oedema, tension, headache, constipation, depression

Progesterogenic effects

  • Diosgenin not converted to progesterone in human body
  • Herbal effects on blood levels of progesterone
  • No effect of wild yam creams on salivary progesterone levels


  • External treatment with aloe vera gel
  • IL-10 deficiency in psoriasis
  • Mast cell-bacteria complex modulate immune reaction in psoriasis
  • Minor Bupleurum Formulation induces IL-10
  • Psoriasis, chronic, improves with topical Berberis aquifolium
  • Treatment of psoriasis with sarsaparilla

Sedative effects

  • Chamomile tea has sedative effect
  • Citronellol from Melissa has sedative effects
  • Improvement of sleep quality with Valeriana and Melissa
  • Inhalation of chamomile oil has sedative effect
  • Remedy containing oil from Melissa has sedative effect
  • Zizyphus combination for insomnia
  • Zizyphus combination for sleep disorders

Skin response

  • Celery, fennel & parsley not photosensitising
  • Psoralen may lead to photosensitivity
  • Treatment of dermatitis with topical chamomile
  • Treatment of eczema with topical chamomile


  • Chamomile mouthwash efficacy assessed


  • Treatment of syphilis with sarsaparilla

Varicose vein

  • Reduce pain, inflammation and improve blood flow


  • Topical chamomile applications increase rate of wound healing

Pharmacological Studies


  • Treatment of uterine adenomyosis with Paeonia and Glycyrrhiza

Adverse effects

  • Stevioside and rebaudioside A are not cariogenic
  • Stevioside does not affects growth or reproduction


  • Treatment of alcoholism with herbs

Alterative effects

  • Alterative effect of smilax

Anti-allergic effects


  • Anti-allergic activity of Glycyrrhiza glabra, Magnolia officinalis and Scutellaria baicalensis

Anti-cancer activity

  • Apigenin inhibits carcinogenesis
  • Cytotoxic and antibacterial activity of boneset
  • Green tea acts as anti-promoter against PCP-induced hepatocarcinogenesis
  • Green tea and caffeine show inhibitory effects on UV-induced carcinogenesis
  • Green tea consumption may prevent or delay growth of human cancer
  • Inhibition of carcinogen-induced immune suppression
  • Isoflavones may reduce cancer risk
  • Picrorrhiza shows anti-tumour and ant-carcinogenic activity
  • Protection against chemical carcinogenesis by Emblica, Phyllanthus, Picrorrhiza

Anti-complementary activity

  • Flavonoids from Olea europaea leaves show anti-complementary activity

Anti-inflammatory activity

  • Alpha-bisabolol has antiphlogistic and analgesic effects
  • Andrographolide shown to have anti-inflammatory activity
  • Angelica polysaccharides have anti-inflammatory activity
  • Angelica sinensis shows healing effect on gastric mucosa
  • Anti-inflammatory activity of chamomile applied topically
  • Anti-inflammatory effect of ginkgo – inhibition of polymorphonuclear leukocytes
  • Anti-inflammatory effects of chamomile
  • Antiphlogistic effect of saponins
  • Chamazulene has antiphlogistic properties
  • Filipendula inhibits complement activation
  • Flavonoids inhibit oedema
  • Inflammation inhibited by topical apigenin
  • Matricine has anti-inflammatory action
  • Matricine has anti-inflammatory effects
  • Paeonia and Coptis inhibit AA biotransformation
  • Plants show anti-inflammatory activity
  • Platelet activating factor- inhibition
  • Polygonum bistorta has anti-inflammatory action
  • Polygonum bistorta, Guaiacum officinale and Hamamelis virginiana contain anti-inflammatory substances
  • Rosmarinic acid inhibits C5a generation.
  • Rosmarinic acid inhibits inflammatory processes
  • Smilax has anti-inflammatory effect in rats
  • Topical Angelica leaf extract is anti-inflammatory
  • Topical application of chamomile has anti-inflammatory effects

Anti-thyrotrophic effects

  • Melissa decreases TSH-binding inhibitory activity
  • Melissa inhibits T4 to T3 conversion
  • Melissa inibits binding of TSH on thyroid gland


  • Andrographis shows antihyperglycaemic and antioxidant properties
  • Plants with antihyperglycaemic effects

Antimicrobial activity

  • Alpha-bisabolol has antimicrobial properties
  • Antibacterial effects of chamomile against Staphylococcus and Streptococcus
  • Antifungal activity of compounds from Juniperus communis
  • Antimicrobial activity against E. coli
  • Antimicrobial activity of Olea europaea
  • Bactericidal activity of fermented hot-water extract of stevia
  • Berberine is antimicrobial
  • Chamomile has bacterial and fungicidal activities
  • Chamomile oil inactivates bacterial toxins
  • Essential oil of Melissa has anti-fungal activity
  • Essential oil of Melissa has antibacterial and fungostatic effects
  • Filipendula has antibiotic action
  • Growth of Staphylococcus and Streptococcus inhibited by chamomile
  • Lavandula officinalis, Melissa officinalis and Rosmarinus officinalis show antimicrobial effects
  • Miticidal activities of Lavandula angustifolia
  • Umbelliferone is fungostatic

Antimutagenic action

  • Angelica has antimutagenic effects
  • Rosmarinus and Melissa have antimutagenic action

Antinitotinic effects

  • Xanthotoxol has anti-nitotinic effects

Antioxidant effects

  • Angelica sinensis demonstrates antioxidant activity
  • Antioxidant activity of Echinacea root extract.
  • Chamazulene inhibits leukotriene B4 formation
  • Chamomile shows antioxidant activities
  • Flavonoids from baical scullcap show protective effects on oxidative injury
  • Flavonoids from baical skullcap show free radical scavenging ability
  • Green tea has antioxidant properties
  • Green tea polyphenols have antioxidant activity
  • Melissa extract has antioxidant activities
  • Melissa has antioxidant activities
  • Salvia officinalis, Melissa officinalis and Lavandula angustifolia show antioxidant effects
  • Zizyphus has antioxidant effects and inhibits lipid peroxidation
  • Zizyphus has free radical scavenging effects
  • Zizyphus shows antioxidant effects

Antiproliferative activity

  • Berberis aquifolium inhibits keratiocytes
  • Effects of emodin on Ehrlich ascites carcinoma cells
  • Emodin has an inhibitory effect on leukaemia cells
  • Genistein inhibits cell proliferation and in vitro angiogenesis

Antispasmodic activity

  • Viburnum prunifolium inhibits spontaneous contractions
  • Viburnum prunifolium shows spasmolytic activity

Antiulcerogenic activity

  • Alpha-bisabolol is antiulcerogenic
  • Bisabolol has antiulcerogenic effects
  • Chamomile shows antiulcerogenic activity
  • Filipendula decoction reduces ulcerogenic action
  • Filipendula extract has preventative action agains ulcers
  • Gastric mucosal lesions, prevention by Centella asiactica

Antiviral activity

  • Apigenin inhibits herpes viruses
  • Apigenin inibits HIV activation
  • Chamomile inhibits herpes virus
  • Chamomile inhibits polio virus
  • Melissa applied topically has virostatic action
  • Melissa constituents have anti-viral properties
  • Melissa treatment for herpes simplex
  • Melissa used topically for herpes simplex
  • Polygonum bistorta has interferon inducing abilities


  • Anti-tumour effects on human prostate cancer cells

Calcium blocking activity

  • Andrographis shown to selectively block calcium channels
  • Angelica has calcium-antagonist-like effects

Cardiovascular activity

  • Angelica sinensis has antiplatelet effect
  • Angelica sinensis has cardiotonic activity
  • Angelica sinensis reduces atherogenesis
  • Antihypertensive effects of Allium sativum and Olea europaea
  • Antiplatelet activity of Angelica sinensis
  • Apigenin relaxes rat thoracic aorta
  • Atherogenesis development reduced by Angelica sinensis
  • Beneficial effects of Dioscorea nipponica and D. caucasia on the cardiovascular system
  • Berberine has cardiotonic activity
  • Berberine is antiarrhythmic
  • Coleus activates adenylate cyclase
  • Filipendula has anti-coagulant and fibrinolytic activity
  • Filipendula shows anticoagulant and fibrinolytic activity
  • Forskolin has positive inotropic action
  • Forskolin inhibits human platelet aggregation
  • Forskolin lowers blood pressure
  • Herbal formula protects against reperfusion injury
  • Paeonia prolongs prothrombin time and partial thromboplastin time
  • Protection against reperfusion injury with Angelica sinensis
  • Stevia acts as a vasodilator agent
  • Stevioside effective in blood pressure reduction
  • Vasodilator effect of Olea europaea
  • Zizyphus has cardioprotective activity
  • Zizyphus protects against ischaemic injuries
  • Zizyphus shows cardioprotective activity

Central nervous system response

  • Alpha-bisabolol is antispasmodic
  • Antispasmodic effect of chamomile and its constituents
  • Apigenin has antispasmodic activity
  • Apigenin shows anxiolytic and sedative activity
  • Aporphine alkaloids may act on benzothiazepine receptors
  • Chamomile has sedative effect
  • Chamomile has sedative effect on CNS
  • Filipendula extract has CNS depressent effect
  • Hypericum is anxiolytic and affects exploratory behavior in rats
  • Melissa has sedative effect
  • Zizyphus has sedative action
  • Zizyphus has sedative and hypnotic effects

Choleretic activity

  • Berberine stimulates the secretion of bile and bilirubin
  • Chamomile increases bile production

Connective tissue regenerator

  • Alpha-bisabolol promotes granulation and tissue regeneration
  • Alpha-bisabolol shortens healing time of burns


  • Constituents of Olea europaea leaves


  • Inhibition of the enzymes MAO and aldehydedehydrogenase

Diuretic effects

  • Smilax has diuretic action

Dopamine metabolism

  • Doperminergic activity: inhibition of prolactin

Effects on blood

  • Angelica sinensis enhances haematopoiesis
  • Treatment of blood stagnation

Gastrointestinal effects

  • Imbalances of intestinal bacteria treated with chamomile
  • Smilax improves appetite and digestion


  • Anti-inflammatory activity

Hepatic effects

  • Apium and Hygrophila shown hepatoprotective activity
  • Experimental cholangitis
  • Paeonia and Salvia miltiorrhiza protect hepatocytes
  • Smilax has hepatoprotective effect in rats
  • Stevioside affects hepatic glycogen synthesis


  • Wogonin from baical scullcap suppresses HBV surface antigen production

Hormonal effects

  • Effects of Paeonia and Glycyrrhiza on oestrogen and progesterone secretion
  • Oestrogenic activity of Chamaelirium luteum and other herbs
  • Oestrogenic effect of diosgenin
  • Paeonia and Glycyrrhiza combination increases DHEA-S
  • Paeonia and Glycyrrhiza decrease prostaglandin production
  • Paeonia and Glycyrrhiza lower prolactin levels
  • Paeonia stimulates oestradiol secretion
  • Vitex affects hormone levels
  • Vitex inhibits prolactin
  • Vitex inhibits prolactin release
  • Vitex inhibits prolactin secretion
  • Vitex seeds have progesterone-like effects

Hypocholesterolaemic effects

  • Olea europea for hypercholesterolaemia and diabetes
  • Reduction of plasma cholesterol levels with Dioscorea
  • Stimulation of biliary cholesterol output with diosgenin
  • Treatment of atherosclerosis with saponins of Dioscorea
  • Treatment of hypercholesterolaemia with diosgenin

Hypoglycaemic activity

  • Development of streptozotocin diabetes retarded by plant treatments
  • Growth, hypotension, hypoglycaemia and hypouricaemia due to Olea europaea
  • Hypoglycaemic activity of juniper berries
  • Hypoglycaemic activity of olive leaf
  • Picrorrhiza shows anti-diabetic activity
  • Stevioside and steviol stimulate insulin secretion via direct action on beta cells

Immunomodulatory effects

  • Chamomile increases T-lymphocyte rosette formation
  • Echinacea and golden seal increase antigen-specific Ig production
  • Echinacea purpurea rejuvenates natural killer cells
  • Echinacea stimulates production of cells responsible for immunity
  • Extracts enhance proliferation of lymphocytes after stimulation with allogenic cells in vitro
  • Herbs improve phagocytosis of erythrocytes
  • IL-2 production promoted by dong quai and astragalus
  • Immunopharmacological activity of Echinacea


  • Turnera diffusa and Pfaffia paniculata as sexual stimulants

Inhibition of lipoxygenase, lipid peroxidation

  • B. aquifolium inhibits lipid peroxidation
  • Berberine and other alkaloids inhibit lipoxygenase
  • Bisbenzyllisoquinoline alkaloids isolated from Berberis aquifoliuim inhibit lipid peroxidation
  • Chamazulene inhibits lipid peroxidation

Inhibition of protein biosynthesis

  • Caffeic acid inhibits protein biosynthesis
  • Melissa extract inibits protein biosynthesis
  • Melissa inibits protein biosynthesis

Lipogenesis inhibition

  • Berberine suppresses lipogenesis


  • Alkamide levels in Echinacea purpurea: effects of processing, drying and storage.
  • Retention of alkamides in dried echinacea purpurea.

Metabolic and endocrine activity

  • Coleus has thyroid stimulating-hormone-like effect
  • Coleus improves sugar metabolism
  • Coleus maintains lipolysis in catecholamine deficiency
  • Coleus stimulates amylase and pepsinogen synthesis
  • Coleus stimulates lipolysis in adipocytes
  • Forskolin stimulates hormone production

Mucous membrane irritation

  • Evidence for bioadhesive effects of polysaccharides on buccal membranes

Ocular response

  • Bergapten and 8-methoxypsoralen cause photosensitivity
  • Forskolin lowers intra-ocular pressure

Oestrogen (estrogen) receptors

  • New oestrogen receptor ER alpha
  • Oestrogenic activity of 8-prenylnaringenin from hops

Renal function

  • Influence of renal function on diacerein

Respiratory response

  • Adhatoda vasica has antitussive properties
  • Compounds from onion, galphimia, adhatoda, picrorrhiza for treatment of bronchial asthma

Skin disorders

  • Betrgapten and 8-methoxypsoralen for vitiligo and psoriasis

Smooth muscle respons

  • Angelica root oil has relaxant effects in smooth muscle
  • Angelicin has relaxant activity on smooth muscles
  • Coleus relaxes smooth muscle
  • Dose dependent effects of Dioscorea nipponica on smooth muscle
  • Filipendula extract normalises RNA content in gastric tissue
  • Filipendula increases tone in isolated smooth muscle

Synergistic effects

  • Saponins facilitate phytochemical absorption

Tonic effects

  • Zizyphus has tonic effect
  • Zizyphus increases recovery time

Toxicity reduction

  • Olive leaf reduces streptozotocin-induced tissue injury

Uterine tonic

  • Angelica sinensis has stimulating action on uterus
  • Chamomile has uterine tonic effect