|Grade||Level of Evidence|
|A||Multiple double-blind, controlled clinical trials.|
|B||1 double-blind, controlled clinical trial.|
|C||At least 1 controlled or comparative clinical trial.|
|D||Uncontrolled, observational, animal or in-vitro studies only.|
|Grade||Effect||Size of Effect||Comments|
Appears to improve symptoms of atopic dermatitis, neurodermatitis and toxic degenerative eczema.
Efficiently scavenges reactive oxygen and reactive nitrogen species, preventing them from damaging skin cells. Also capable of regenerating vitamin E, another important skin antioxidant.
Reduced water loss and erythema in skin irritated by sodium lauryl sulphate (SLS).
May protect against UVB radiation, possibly on account of its anti-inflammatory and antimutagenic effect.
Inhibits the activities of myeloperoxidase and collagenase, enzymes understood to impair wound healing.
Exhibited weak anti-collagenase activity in 2 in vitro assays.
A witch hazel distillate, but not 2 witch hazel extracts, showed anti-elastase activity in vitro.
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Table of contents:
- 1. Sources
- 2. Bioavailability
- 3. Effects on the skin
- 4. Safety
Witch hazel is distilled from the leaves and bark of the American witch-hazel Hamamelis virginiana, a shrub common in deciduous forests ranging from Nova Scotia to Wisconsin and south to Florida and Texas. The plant had long used in the southern and westerm portion of the United States as a remedy for all forms of wounds and bruises, but witch hazel was first produced commercially in Essex, Connecticut, in 1846.
The leaves, twigs and bark of the witch-hazel shrub contain a number of active compounds, such as tannins, catechins, gallic acid, hydroxycinnamic acids and flavonol glucosides plus their corresponding aglycones quercetin and kaempferol.
A recent review of 52 moisturizers for acne found that witch hazel was included in 10 products (19%), presumably as an anti-inflammatory agent.
We were not able to find any published data on the skin penetration or topical bioavailability of witch hazel, though a study referenced in the European Medicines Agency's witch hazel assessment claimed that witch hazel extracts applied locally in therapeutic amounts do not penetrate into the deeper layers of the skin because of the astringency of its constituents.
3. Effects on the skin
3.1 Antioxidant action
Witch hazel possesses strong antioxidant activity. Trolox equivalent antioxidant capacity (TEAC) assays show that witch hazel extract has higher antioxidant activity than extracts of rose, orange flowers, pomegranate and mahonia, but lower than that of white tea.
Witch hazel extracts have been found be a potent scavenger of reactive species such as peroxynitrite and superoxide anions, hydroxyl radicals and singlet oxygen. In fact, it scavenges superoxide anions more effectively than vitamin C and vitamin E, and hydroxyl radicals more effectively than vitamin E.
Further, witch hazel has high superoxide dismutase mimetic activity and appears to be able to regenerate vitamin E by efficiently reducing α-tocopherol radicals, contributing to its antioxidant effect.
The pyrogallol-containing polyphenols (proanthocyanidins, gallotannins, and gallates) present in witch hazel are thought to be responsible for its antioxidant effects.
Whether witch hazel protects against UV radiation is open to question. Lotions containing witch hazel distillate/extract can suppress UV-induced erythema in humans in vivo to a greater extent compared to their vehicies, but the difference is not always statistically significant. The protection provided, if any, has been linked to witch hazel's anti-inflammatory and anti-mutagenic effects, and it increases with the addition of UVB sunscreens such as octinoxate.
3.3 Age-related improvements
Apart from protecting the skin against photodamage, witch hazel may also have the potential to improve photoaged skin. A witch hazel extract had a weak (~15%) anti-collagenase activity in two in vitro assays, and no significant anti-elastase activity. However, a witch hazel distillate from the same supplier showed very strong (41%) anti-elastase activity and no detectable activity against a bacterial collagenase, indicating that the extraction process may be important in obtaining extracts with the most highest anti-aging potency, perhaps due to differences in composition.
3.4 Anti-inflammatory action
Witch hazel contains anti-inflammatory substances, as evidenced by its ability to inhibit the chronic phase of adjuvant-induced rat paw swelling, croton oil-induced ear edema in the mouse and IL-8 production by fibroblasts.
In particular, hamamelitannin and the galloylated proanthocyanidins isolated from witch hazel are powerful inhibitors of 5-lipoxygenase, the key enzyme involved in the biosynthesis of leukotrienes, which are considered potent mediators of inflammatory and allergic reactions.
Witch hazel's anti-inflammatory effect is inferior to hydrocortisone, but superior to that of chamomile.
3.5 Anti-microbial activity
Witch hazel is an antiseptic. Its methanol extracts were active against many species of periodontopathic bacteria, and the aqueous extracts of its leaves and bark inhibited the growth of E. coli, S. aureus, B. subtilis and E. faecalis. In addition, a topical dermatological formulation containing 90% witch hazel distillate and 5% urea weakly inhibited the bacterium S. aureus and the fungus C. albicans, among other organisms.
Extracts of the bark of the witch-hazel shrub have also been shown to exhibit significant anti-viral activity against Herpes simplex virus type 1 (HSV-1) and influenza A virus, and to inhibit human papillomavirus type 16 (HPV-16) infection. The main anti-viral principle is thought to be the tannins, with gallic acid and epigallocatechin gallate (EGCG) also playing a part, since removal of tannins from the extract abolished its anti-viral effect against the H1N1 virus only if gallic acid and EGCG were not present in large amounts. There is evidence that the high molecular weight tannins inhibit viral attachment, whereas EGCG has been proposed to work via inhibition of viral attachment , inhibition of endosomal acidification , membrane damage  or virus aggregation. The anti-viral mechanism of gallic acid has yet to be determined.
3.6 Improved healing
Cross-linked collagen sponges loaded with witch hazel polyphenols inhibited the activity of myeloperoxidase and chitosan/gelatin hydrogels inhibited the activity of both myeloperoxidase and collagenase, enzymes known to impair wound healing, in vitro in two separate studies, suggesting that they have the potential to be used in the treatment of chronic wounds.
The detergent cream Anonet Liquid, which contains witch hazel, also helped prevent infections in 84% of 40 patients following coloprotcological surgery for haemorrhoids or chronic anal fissures, by stimulating re-epithelization. However, in this case it is not clear whether witch hazel was responsible for the healing, since the cream also contained many other active ingredients including aloe vera, horse chestnut, marigold, elastin, zinc oxide, rice starch, cod liver oil and potassium glycyrrhizinate.
A wound healing ointment (Hametum Ointment) containing witch hazel distillate as the active ingredient was evaluated for its effects on dry aging skin in an open-label clinical study in 89 subjects aged 50 years or older. After twice daily applications for 4 weeks, there were significant and clinically relevant improvements in the sebum and moisture content of the skin, as measured by sebumetric and corneometric measurements. Scaling and fissures were also clearly reduced, and symptoms of dryness such as skin tautness, roughness and itching had also improved. However, Hametum Ointment uses petrolatum, an excellent occlusive, as its base, so these effects may be due to petrolatum rather than witch hazel.
3.7 Pain relief
Witch hazel water, ice packs and a cream containing 1% hydrocortisone + a local anaesthetic were examined for their effectiveness in achieving analgesia in a randomized clinical trial of 300 pregnant mothers undergoing episiotomy associated with forceps delivery. All 3 agents were equally effective in achieving analgesia on the first day, though approximately a third of the patients derived no benefit from any agent. Thereafter, the ice packs had a tendency to be better, but overall the 3 agents appeared to possess equal efficacy.
3.8 Dermatitis treatment
It has been stated that witch hazel formulations are used in the maintenance treatment of dermatitis because of their anti-microbial, anti-inflammatory, hydrating and barrier-stabilizing properties.
Witch hazel displayed efficacy in an observational study that included 97 infants and children suffering from diaper dermatitis. It was found to be as effective as panthenol, as well as better-tolerated. Treatment with topical witch hazel extract also led to the full recovery of a skin rash on the chin of a patient who experienced sodium hypochlorite-induced skin injury during endodontic treatment.
In a pilot study of 37 patients with atopic dermatitis, a cream containing a witch hazel leaf extract was applied twice daily for 2 weeks. Following treatment, 24 patients (65%) experienced considerable improvement in symptoms such as inflammation and itching.
The first double-blind, placebo-controlled study of a witch hazel preparation (Hametum Ointment) assessed its effectiveness in 80 patients with neurodermatitis or degenerative eczema compared to a control preparation. The results indicated that the ointment was superior in effectiveness in the treatment of atopic dermatitis compared to the control, but that there was no difference in therapeutic effectiveness in the treatment of primary irritant contact dermatitis.
In another randomized, double-blind comparison study, an ointment containing a standardized extract of the dried leaves of witch hazel was compared to the anti-inflammatory agent bufexamac in the treatment of 22 patients with atopic dermatitis. Patients were treated thrice daily for 5-22 days, and post-treatment comparisons of the patients' forearms showed that both treatments reduced desquamation, redness, itching, infiltration and lichenification equally well.
However, a third double-blind, randomized and paired trial that enrolled 72 patients with moderately severe atopic dermatitis revealed that its effect was no different from that of the vehicle, and inferior to treatment with a hydrocortisone cream.
3.9 Anti-cancer effect
Fractions of witch hazel bark extract rich in proanthocyanidins, gallotannins, and gallates inhibited the proliferation of human skin melanoma cells at concentrations lower than grape and pine procyanidins, possibly due to their powerful antioxidant action. In human colon cancer cell lines, too, they exhibited cytotoxic and anti-proliferative effects, reducing tumour viability, arresting the cell cycle at the S phase and inducing apoptosis and necrosis.
Further, a recent study demonstrated that witch hazel root has the ability to inhibit lactate dehydrogenase A, an enzyme that is highly expressed in human malignant tumours and which is thought to contribute to aggressive tumour growth, advanced tumour progression, metastasis, immune evasion as well as resistance to radiation and chemotherapy.
3.10 Other effects and uses
Witch hazel appears to have been held in high regard as a therapeutic agent in the late 19th century. A dermatologist from that period deemed it a powerful astringent and haemostatic, and therefore an excellent remedy for gastric haemorrhage, menorrhagia, nosebleeds and hemophilia. It was also considered effective in resolving purpura, treating varicose veins and ulcers, haemorrhoids, diarrhea, leukorrhea and gonorrhea. External applications included hyperidrosis, rosacea, seborrhea, intertrigo and some forms of pruritus.
Hamamelitannin in witch hazel protects endothelial cells from tumour necrosis factor-alpha (TNF)-induced DNA fragmentation and cell death in vitro, as well as the green tea polyphenol epigallocatechin gallate (EGCG) and more effectively than gallic acid. This activity is thought to explain the anantihamorrhaegic use of witch hazel in traditional medicine and its use as a photoprotective agent, since TNF is known to cause haemorrhagic disorders and has been shown to play a role in UVB-mediated cell damage.
An extract of witch-hazel bark has also been shown to inhibit α-glucosidase and human leukocyte elastase, enzymes that contribute to the degradation of connective tissue and hence compromise vascular integrity. This may account for the use and effectiveness of witch hazel in treating varicose veins and haemorrhoids, 2 common manifestations of venous insufficiency.
The proanthocyanidins in witch hazel may have barrier repair properties, as they decreased transepidermal water loss (TEWL) and erythema formation in vivo on skin that had been irritated by sodium lauryl sulphate. They also strongly increased the proliferation of cultured human keratinocytes.
Prrikweg gel, a homeopathic gel containing witch hazel extract and meant for use after insect bites, was judged to have inhibited erythema formation, but not itching, after bites by Aedes aegypti mosquitoes under laboratory conditions in a double-blind and placebo-controlled trial. The relevance of this study is not clear however, because the gel also includes tinctures of the narrow-leaved purple coneflower, northern Labrador tea and small nettle, all of which may be responsible for the observed effect.
Finally, witch hazel was the second most bioactive extract out of 49 herb, spice and medicinal plant extracts tested in an assay on the insulin-dependent utilization of glucose using rat epididymal adipocytes, suggesting that it may improve cells' glucose and insulin metabolism.
Witch hazel is permitted by the US FDA as an astringent in over-the-counter (OTC) skin protectant and anorectal drug products. Because the safety of witch hazel has been assessed by the FDA, the Cosmetic Ingredient Review (CIR) has deferred its evaluation, but the Committee on Herbal Medicinal Products (HMPC) of the European Medicines Agency regards the external application of witch hazel preparations as safe for cutaneous use at their recommended doses.
4.1 Adverse events
Ingestion of witch hazel is not expected to cause significant adverse effects, but topical application may cause contact allergy in rare cases in sensitive individuals, as has been reported in the literature.
In an observational study, 11 out of 231 (5%) children with minor skin injuries, diaper dermatitis, or localized skin inflammation who were treated with witch hazel experienced adverse events such as confusion, head lice, cough/allergic reaction, fungal infection/deterioration, otitis, increased erythema, rhinopharyngitis, burning sensation, super-infection, diaper candidiasis, and obstructive bronchitis, but only the burning sensation and erythema were considered to potentially be related to the treatment.
There are also records of 14 adverse drug reactions to witch hazel in herbal remedies.
4.2 No evidence of genotoxicity
Witch hazel water was negative in 5 Salmonella mutagenicity assays in the presence and absence of metabolic activation. Witch hazel was also not identified as a mutagen in a mouse lymphoma cell forward mutation assay, nor did it induce sex-linked recessive lethal mutations in Drosophila melanogaster.
In fact, a tincture and a methanolic extract of witch-hazel bark dose-dependently inhibited 2-nitrofluorene-induced mutagenicity in Salmonella typhimurium TA98 by 60% and 54% respectively at 100 μl/plate, with the antimutagenic effect increasing with the increasing degree of polymerisation of the proanthocyanidins. Catechin and proanthocyanidin fractions from witch-hazel bark were also found to significantly reduce benzo(a)pyrene-induced DNA damage in a human derived, metabolically competent hepatoma cell line. The protective effects seemed to be due to scavenging of the ultimate metabolite of benzo(a)pyrene, (+/-)-anti-benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), and not the activation of DNA repair mechanisms. Hamamelitannin has also been shown to inhibit DNA fragmentation in human endothelial cells.
4.3 No evidence of carcinogenicity
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