Fish Oil for Psoriasis
One of the most common supplements used by patients with psoriasis is fish oil due to its purported anti-inflammatory qualities.20,39 The consensus on fish oil supplementation for psoriasis is mixed.43-45 Multiple RCTs have reported reductions in psoriasis area and severity index (PASI) scores or symptomatic improvement with variable doses of fish oil.44,46 One RCT found that using EPA 1.8 g once daily and DHA 1.2 g once daily for 12 weeks resulted in significant improvement in pruritus, scaling, and erythema (P<.05).44 Another study reported a significant decrease in erythema (P=.02) and total body surface area affected (P=.0001) with EPA 3.6 g once daily and DHA 2.4 g once daily supplementation compared to olive oil supplementation for 15 weeks.46 Alternatively, multiple studies have failed to show statistically significant improvement in psoriatic symptoms with fish oil supplementation at variable doses and time frames (14–216 mg daily EPA, 9–80 mg daily DHA, from 2 weeks to 9 months).40,47,48 Fish oil may impart anticoagulant properties and should not be started without the guidance of a physician. Currently, there are no data to make specific recommendations on the use of fish oil as an adjunct psoriatic treatment.
Curcumin for Psoriasis
Another supplement routinely utilized in patients with psoriasis is curcumin,40,49,50 a yellow phytochemical that is a major component of the spice turmeric. Curcumin has been shown to inhibit certain proinflammatory cytokines including IL-17, IL-6, IFN-γ, and tumor necrosis factor α and has been regarded as having immune-modulating, anti-inflammatory, and antibacterial properties.40,50 Curcumin also has been reported to suppress phosphorylase kinase, an enzyme that has increased activity in psoriatic plaques that correlates with markers of psoriatic hyperproliferation.50,51 When applied topically, turmeric microgel 0.5% has been reported to decrease scaling, erythema, and psoriatic plaque thickness over the course of 9 weeks.50 In a nonrandomized trial with 10 participants, researchers found that phosphorylase kinase activity levels in psoriatic skin biopsies of patients applying topical curcumin 1% were lower than placebo and topical calcipotriol applied in combination. The lower phosphorylase kinase levels correlated with level of disease severity, and topical curcumin 1% showed a superior outcome when compared to topical calcipotriol.40,49 Although these preliminary results are interesting, there still are not enough data at this time to recommend topical curcumin as a treatment of psoriasis. No known adverse events have been reported with the use of topical curcumin to date.
Oral curcumin has poor oral bioavailability, and 40% to 90% of oral doses are excreted, making supplementation a challenge.40 In one RCT, oral curcumin 2 g daily (using a lecithin-based delivery system to increase bioavailability) was administered in combination with topical methylprednisolone aceponate 0.1%, resulting in significant improvement in psoriatic symptoms and lower IL-22 compared to placebo and topical methylprednisolone aceponate (P<.05).52 Other studies also have reported decreased PASI scores with oral curcumin supplementation.53,54 Adverse effects reported with oral curcumin included gastrointestinal tract upset and hot flashes.53 Although there is early evidence that may support the use of oral curcumin supplementation for psoriasis, more data are needed before recommending this therapy.
Indigo Naturalis for Psoriasis
Topical indigo naturalis (IN) also has been reported to improve psoriasis symptoms.39,53,55 The antipsoriatic effects are thought to occur through the active ingredient in IN (indirubin), which is responsible for inhibition of keratinocyte proliferation.40 One study reported that topical IN 1.4% containing indirubin 0.16% with a petroleum ointment vehicle applied to psoriatic plaques over 12 weeks resulted in a significant decrease in PASI scores from 18.9 at baseline to 6.3 after IN treatment (P<.001).56 Another study found that over 8 weeks, topical application of IN 2.83% containing indirubin 0.24% to psoriatic plaques vs petroleum jelly resulted in 56.3% (n=9) of the treatment group achieving PASI 75 compared to 0% in the placebo group (n=24).55 One deterrent in topical IN treatment is the dark blue pigment it contains; however, no other adverse outcomes were found with topical IN treatment.56 Larger clinical trials are necessary to further explore IN as a potential adjunct treatment in patients with mild psoriatic disease. When taken orally, IN has caused gastrointestinal tract disturbance and elevated liver enzyme levels.57
It is important to consider that oral supplements including curcumin and IN are widely available over-the-counter and online without oversight by the US Food and Drug Administration.40 Herbal supplements typically are compounded with other ingredients and have been associated with hepatotoxicity as well as drug-supplement interactions, including abnormal bleeding and clotting.58 There exists a lack of general surveillance data, making the true burden of herbal toxicities more difficult to accurately discern. Although some supplements have been associated with anti-inflammatory qualities and disease improvement, other herbal supplements have been shown to possess immunostimulatory characteristics. Herbal supplements such as spirulina, chlorella, Aphanizomenon flos-aquae, and echinacea have been shown to upregulate inflammatory pathways in a variety of autoimmune skin conditions.59
Probiotics for Psoriasis
Data on probiotic use in patients with psoriasis are limited.23 A distinct pattern of dysbiosis has been identified in psoriatic patients, as there is thought to be depletion of beneficial bacteria such as Bifidobacterium, lactobacilli, and F prausnitzii and increased colonization with pathogenic organisms such as Salmonella, E coli, Heliobacter, Campylobacter, and Alcaligenes in psoriasis patients.23,59,60 Early mouse studies have supported this hypothesis, as mice fed with Lactobacillus pentosus have developed milder forms of imiquimod-induced psoriasis compared to placebo,55 and mice receiving probiotic supplementation have lower levels of psoriasis-related proinflammatory markers such as TH17-associated cytokines.61 Another study in humans found that daily oral Bifidobacterium infantis supplementation for 8 weeks in psoriatic patients resulted in lower C-reactive protein and tumor necrosis factor α levels compared to placebo.62 Studies on the use of topical probiotics in psoriasis have been limited, and more research is needed to explore this relationship.38 At this time, no specific recommendations can be made on the use of probiotics in psoriatic patients.
Alopecia areata is nonscarring hair loss that can affect the scalp, face, or body.63,64 The pathophysiology of AA involves the attack of the hair follicle matrix epithelium by inflammatory cells without hair follicle stem cell destruction. The precise events that precipitate these episodes are unknown, but triggers such as emotional or physical stress, vaccines, or viral infections have been reported.65 There is no cure for AA, and current treatments such as topical minoxidil and corticosteroids (topical, intralesional, or oral) vary widely in efficacy.64 Although Janus kinase inhibitors recently have shown promising results in the treatment of AA, the need for prolonged therapy may be frustrating to patients.66 Severity of AA also can vary, with 30% of patients experiencing extensive hair loss.67 The use of CAM has been widely reported in AA due to high levels of dissatisfaction with existing therapies.68 Herein, we discuss the most studied alternative treatments used in AA
Garlic and Onion for Alopecia
One alternative treatment that has shown promising initial results is application of topical garlic and onion extracts to affected areas.64,69,70 Both garlic and onion belong to the Allium genus and are high in sulfur and phenolic compounds.70 They have been reported to possess bactericidal and vasodilatory activity,71 and it has been hypothesized that onion and garlic extracts may induce therapeutic effects through induction of a mild contact dermatitis.70 One single-blinded, controlled trial using topical crude onion juice reported that 86.9% (n=20) of patients had full regrowth of hair compared to 13.3% (n=2) of patients treated with a tap water placebo at 8 weeks (P<.0001). This study also noted that patients using onion juice had a higher rate of erythema at application site; unfortunately, the study was small with only 38 patients.70 Another double-blind RCT using garlic gel 5% with betamethasone valerate cream 0.1% compared to betamethasone valerate cream alone found that after 3 months, patients in the garlic gel group had increased terminal hairs and smaller patch sizes compared to the betamethasone valerate cream group.69 More studies are needed to confirm these results.
Aromatherapy With Essential Oils for Alopecia
Another alternative treatment in AA that has demonstrated positive results is aromatherapy skin massage with essential oils to patches of alopecia.72 Although certain essential oils, such as tea tree oil, have been reported to have specific antibacterial or anti-inflammatory properties, essential oils have been reported to cause allergic contact dermatitis and should be used with caution.73,74 For example, tea tree oil is a well-known cause of allergic contact dermatitis, and positive patch testing has ranged from 0.1% to 3.5% in studies assessing topical tea tree oil 5% application.75 Overall, there have been nearly 80 essential oils implicated in contact dermatitis, with high-concentration products being one of the highest risk factors for an allergic contact reaction.76 One RCT compared daily scalp massage with essential oils (rosemary, lavender, thyme, and cedarwood in a carrier oil) to daily scalp massage with a placebo carrier oil in AA patients. The results showed that at 7 months of treatment, 44% (n=19) of the aromatherapy group showed improvement compared to 15% (n=6) in the control group.77 Another study used a similar group of essential oils (thyme, rosemary, atlas cedar, lavender, and EPO in a carrier oil) with daily scalp massage and reported similar improvement of AA symptoms compared to control; the investigators also reported irritation at application site in 1 patient.78 There currently are not enough data to recommend aromatherapy skin massage for the treatment of AA, and this practice may cause harm to the patient by induction of allergic contact dermatitis.
There have been a few studies to suggest that the use of total glucosides of peony with compound glycyrrhizin and oral Korean red ginseng may have beneficial effects on AA treatment, but efficacy and safety data are lacking, and these therapies should not be recommended without more information.64,79,80
Dermatologic patients frequently are opting for CAM,2 and although some therapies may show promising initial results, alternative medicines also can drive adverse events.19,30 The lack of oversight from the US Food and Drug Administration on the products leads to many unknowns for true health risks with over-the-counter CAM supplements.40 As the use of CAM becomes increasingly common among dermatologic patients, it is important for dermatologists to understand the benefits and risks, especially for commonly treated conditions. More data is needed before CAM can be routinely recommended.