Chinese skullcap holds a special place among traditional Chinese medicine remedies. It is claimed to relieve allergies, infections, and inflammation. It’s also popular for reducing hair loss and thought to relieve anxiety, although the evidence to support these uses is limited. Discover the potential health benefits unique to this herb and what to look out for when taking it.
What Is Chinese Skullcap?
Chinese skullcap (Scutellaria baicalensis), also known as Baikal skullcap is a plant that belongs to the mint family (Lamiaceae). The plant gets its name due to the shape of its flower, resembling medieval helmets called skullcaps. Over 300 species of skullcap plants exist [1, 2].
The dried roots of the plant have been used in traditional Chinese medicine (TCM) for over 2,000 years. A tincture or decoction (boiled with water) of the root is known as Huang-Qin, which means “golden herb” [1].
TCM practitioners consider Chinese skullcap root a remedy for diarrhea, high blood pressure, insomnia, and gut and lung infections. In TCM and Japanse traditional medicine, it is almost always used as part of multi-herb formulations. In China, it’s even classified as a drug [1].
Animal and cellular studies uncovered its powerful antioxidant and antimicrobial effects. Research also hints at its anti-cancer properties. However, few clinical studies have been carried out.
Blue Skullcap vs Chinese Skullcap
Blue skullcap (Scutellaria lateriflora), also known as American skullcap, is a related plant in the same family as Chinese skullcap. The word “skullcap” can refer to either species.
While it contains many of the same active compounds, blue skullcap has a different chemical profile and distinct potential effects. Blue skullcap has been well-researched for improving mood and reducing anxiety – unlike Chinese skullcap [3, 4].
This post will focus solely on Chinese skullcap.
Snapshot
Proponents
- A long history of use
- May reduces gum inflammation and plaque
- May improve osteoarthritis
- Anti-cancer potential
- Potential to reduce allergic symptoms and fight infections
Skeptics
- Only a few studies in humans
- Often tested in combination with other herbal extracts
- May interact with multiple drugs
- May cause liver damage and lung inflammation
Active Components
The main active components of skullcap are the flavonoids baicalin and wogonoside and their derivatives baicalein and wogonin. They all are found in high levels in the roots, whereas only trace amounts are found in the leaves and stem [1, 4].
Baicalin and wogonoside may be converted to baicalein and wogonin by gut bacteria [5].
Other flavonoids found in skullcap (mostly in the roots) include [6]:
Most of these flavonoids are antioxidants (among these, oroxylin A is the strongest one) [7].
Skullcap also contains [8, 9, 10, 11]:
- Amino acids (glutamine, leucine)
- Fatty acids (linoleic acid, oleic acid)
- Minerals (including potassium, magnesium, phosphorus, calcium, and iron)
- Plant sterols
How It Works
Baicalin and baicalein may contribute to fighting cancer, reducing inflammation, relieving pain, and soothing anxiety. Both compounds increase the production of antioxidants (by activating Nrf2). Wogonoside (and wogonin) add to the potential cancer-fighting, anti-inflammatory benefits [12, 13, 14, 15, 16, 17, 18, 19, 20, 21].
Baicalin may help with anxiety by activating GABA-A and glycine receptors in the brain. Another flavonoid (called K36) also binds to and activates GABA-A receptors as strongly as the anti-anxiety drug Valium [22, 23].
Health Benefits
Note: All studies and health benefits refer to Chinese skullcap (Scutellaria baicalensis) unless stated otherwise.
SelfDecode has an AI-powered app that allows you to see how Chinese skullcap may benefit your personal genetic predispositions. These are all based on clinical trials. The orange neutral faces a typical likelihood of developing health conditions that Chinese skullcap may counteract.
Insufficient Evidence for:
1) Cancer Fight
Although promising, the research on Chinese skullcap’s anticancer potential has been mainly carried out in animals and cells. Further clinical trials are needed to confirm these preliminary results. Importantly, never use Chinese skullcap (or any other supplements) to replace proven anticancer therapies prescribed by your doctor.
The anticancer drug capecitabine was tolerated at doses of up to 1500 mg/m2 when combined with a Chinese botanical formulation containing Chinese skullcap, Chinese licorice, jujube, and Chinese peony (PHY906) in a small trial on 24 people with advanced pancreatic, colorectal, bile duct, and esophageal cancer. The authors of the study suggested that PHY906 may increase the effectiveness of the drug by reducing its side effects such as diarrhea [24].
Chinese skullcap extract increased the production of T cells, red blood cells, and white blood cells by the bone marrow in 2 studies on people with lung cancer receiving chemotherapy, suggesting an improvement of their immune status. Unfortunately, the studies haven’t been translated from Russian and we couldn’t access their specifics for a critical analysis [25, 26].
Similarly, Chinese skullcap enhanced the effectiveness of chemotherapy in mice. The herb enhanced the ability of chemotherapy to prevent the spread of lung cancer and prevented the decrease in blood cells caused by chemotherapy [27, 28].
Acute lymphoblastic leukemia (ALL) is a fast-growing cancer of the blood and bone marrow. In test tubes, Chinese skullcap killed cancerous immune cells of children with ALL without harming healthy cells [29].
In animals, skullcap blocked the growth of skin, colon, and bladder cancers (by causing programmed cell death). In mice, it reduced the size of the skin tumors by 66% and bladder tumors by 30%. Baicalein reduced prostate cancer growth by 55% in mice [30, 31, 32, 33, 34, 35].
In cell-based studies, active compounds from the herb (baicalin, baicalein, and wogonin) prevented the growth and spread of various cancers, including [36, 37, 38, 39, 32, 30]:
- Ovarian
- Breast
- Liver
- Pancreas
- Leukemia
- Bladder
- Colon
2) Gum Inflammation and Plaque
Chinese skullcap might kill dangerous oral bacteria. A toothpaste with skullcap extract greatly reduced gum inflammation and plaque after 21 days in a study of 40 people [40].
In one cell study, skullcap prevented the growth of 8 out of 11 bacteria that cause gum inflammation [41].
A small clinical trial and a cell-based study cannot be considered sufficient evidence that Chinese skullcap improves gum inflammation and reduces plaque buildup. Larger, more robust clinical trials are needed.
3) Osteoarthritis
In 2 clinical trials on 182 people with knee osteoarthritis, a medical food combining Chinese skullcap and Acacia catechu extracts (Flavocoxid) reduced joint pain, stiffness, and mobility as effectively as anti-inflammatory drug naproxen [42, 43].
Although a 250-mg dose 2x/day was safe and well-tolerated in a trial on 59 people followed up for 12 weeks, it has been reported to cause liver injury and lung inflammation in some cases. For this reason, the FDA recalled Flavocoxid in 2018 [44, 45, 46].
4) Allergies
Chinese skullcap’s active compound wogonin reduced the allergic response to mites in human skin cells. When injected into the skin of rats before exposure to an allergen, skullcap reduced the allergic response by decreasing levels of histamine and other inflammatory compounds [47, 48].
Skullcap reduced the inflammatory response to allergenic proteins in mice by decreasing IgE antibodies and cytokine levels (IL-5, IL-10, and IL-13). The herb also prevented allergy-triggering proteins from being absorbed in the gut [49, 50, 51, 52].
However, a Chinese herbal remedy with Chinese skullcap, astragalus, caterpillar fungus, stemona, and fritillaria extracts had no beneficial effects in a clinical trial on 85 children with asthma [53].
Although the research in animals and cells is promising, the only clinical trial carried out so far found Chinese skullcap ineffective. Further clinical research is needed to shed some light on the potential use of this herb by people with allergies.
Animal and Cell Research (Lack of Evidence)
No clinical evidence supports the use of Chinese skullcap for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based research, which should guide further investigational efforts. However, the studies should not be interpreted as supportive of any health benefit.
Fighting Bacteria, Viruses, and Fungi
Traditionally, Chinese skullcap is used to fight off infections, especially respiratory ones. In one cell study, skullcap was more effective in reducing the replication of the swine flu virus than a drug used to treat and prevent the flu (oseltamivir phosphate) [54].
In test tubes, skullcap shows strong antibacterial activity against many different types of bacteria, including [55, 56, 57]:
- E. coli, which can cause UTIs and gut infections
- Staph, which can cause skin and wound infections
- Salmonella and Listeria, possible food contaminants
- The ulcer-causing H. Pylori
It also enhanced the antibacterial activity of antibiotics against resistant superbugs (MRSA) [58, 59].
Some practitioners recommend Chinese skullcap for Lyme disease. Scientific studies have not looked into its effect on the bacteria that causes Lyme disease, though.
Chinese skullcap is also traditionally used to clear toxins and support the liver. Early research reveals it may be active against various viruses, including those that cause hepatitis.
It reduced hepatitis C levels and blocked the virus from replicating in infected mice. Wogonin, its active component, reduced replication of the hepatitis B virus in ducks and improved their liver function [60, 61].
When exposed to HIV, skullcap and its active component baicalin were active against HIV and blocked the activity of enzymes the virus needs to spread [62, 63, 64, 65, 66].
This herb might also kill harmful yeast. In one cell study of 56 widely-used Chinese medicinal plants, skullcap was the most effective in reducing the growth of Candida albicans. Its effectiveness was comparable to the antifungal drug nystatin (Mycostatin) [67].
Note, however, that none of the results have been replicated in humans and, most of them, even in animals. More studies are needed to verify if Chinese skullcap is effective against the infections caused by these microorganisms.
Hair Loss
The same drug that treats prostate enlargement mentioned above – finasteride – might also help reverse baldness [68]. How come?
Male-pattern baldness is caused by a combination of factors, but high levels of DHT and 5-alpha-reductase are among the culprits. By targeting both, skullcap may naturally prevent or reduce hair loss. In test tubes, skullcap blocked the effects of DHT on cells involved in hair growth [69, 70, 71].
The herb’s active compound, baicalin, applied to the skin in mice increased the growth of new hair follicles [72].
Although often used for this purpose, it has only been investigated in animals. Future studies in humans will need to confirm this benefit, though.
Diabetes
In diabetic mice, skullcap reduces oxidative stress, high blood sugar, and insulin levels, thus restoring normal insulin function. This suggests it may be especially useful for type 2 diabetes [73, 74, 75, 76].
Skullcap also reduced high cholesterol and triglyceride levels in diabetic mice. What’s more, its active compounds (baicalin, baicalein, and wogonin) prevented inflammation of the blood vessels caused by high blood sugar levels [73, 74, 77].
Antioxidant
Skullcap prevented the decrease in powerful antioxidant enzymes – superoxide dismutase and glutathione peroxidase – in rabbits fed a high-cholesterol diet. It also increased levels of these same antioxidants in diabetic rats [78, 74].
Liver Health
Herbal formulas containing skullcap are often used to address liver problems [1].
In rats exposed to mold toxins, skullcap prevented DNA damage in the liver and increased the activity of detoxification enzymes. In mice, the herb protected against liver damage from alcohol. In a cell study, skullcap caused unhealthy liver cells to commit suicide, possibly preventing liver scarring (fibrosis) [79, 80, 81].
Baicalin reduced fat buildup in the liver of rats eating a high-fat diet and reduced the activity of genes involved in making and storing fat [82].
Brain Protection
Brain inflammation plays a key role in neurodegenerative diseases, including Parkinson’s disease, Alzheimer’s disease, and multiple sclerosis. Skullcap prevented memory problems in mice with Alzheimer’s. It also reduced immune overactivation and inflammation in the brain cells caused by bacterial toxins (LPS) [83, 84, 85, 86, 87, 88].
In rats, skullcap reduced depression and prevented damage to the hippocampus due to chronic stress. The hippocampus is extremely important for both memory and emotional control [89].
Additionally, baicalin in skullcap protected from brain damage due to stroke and promoted the birth of new brain cells in rats and gerbils [90, 91, 92, 93].
Skullcap also reduced seizures due to electroshock in mice [94].
Enlarged Prostate
DHT is made from testosterone by the action of an enzyme called 5-alpha-reductase. High levels of DHT and this enzyme can lead to prostate enlargement, also known as benign prostate hyperplasia (BPH) [95].
In rats with enlarged prostates, skullcap reduced prostate growth and DHT levels. It was even more effective than finasteride (Propecia), a drug commonly used to treat BPH that blocks 5-alpha-reductase [70].
Weight Loss
Skullcap reduced weight gain in diabetic rats. In another study, long-term supplementation reduced belly fat gain in rats eating a high-fat diet. Importantly, it also reduces blood fat and inflammation while protecting the liver, all of which are crucial for healthy weight loss [73, 82, 96].
Skullcap might work by activating AMPK, an energy-sensing enzyme that increases metabolism and fat-burning. Skullcap also turns off genes that promote fat storage, overall revving energy use in the body [82].
Limitations and Caveats
Nearly all research on skullcap was conducted in animals and cells. In addition, most of the studies in humans have been performed by Chinese or Russian researchers and is inaccessible. Chinese skullcap was sometimes tested as part of multi-herbal formulations, making its specific contribution to the effects observed difficult to estimate.
Dosage & Forms
Because Chinese skullcap is not approved by the FDA for any conditions, there is no official dose. Users and supplement manufacturers have established unofficial doses based on trial and error. Discuss with your doctor if Chinese skullcap may be useful as a complementary approach in your case and which dose you should take.
The roots of skullcap have historically been consumed as a decoction (by boiling the root) or as an alcoholic tincture. The recommended dosage is between 5 and 15 g of dried root daily, as a decoction or tincture. You can also make a tea from the roots by steeping them in hot water [1, 97].
Soaking the dried roots in an herb to water ratio of 1:5 using 122°F (50°C) water for > 1 hour greatly reduces baicalin levels (possibly weakening brain-protective effects) and more than triples wogonin levels (increasing anti-allergy, anti-cancer, and anti-hepatitis B effects) [98].
One of the reasons why dosing skullcap can be complex is because it’s never used alone in traditional Chinese medicine. Instead, it is found in many multi-herb formulations, including [99, 100, 101, 1]:
- Yin Zhi Huang (reduces high bilirubin levels in newborns)
- Soshiho-tang
- Shuang Huang Lian (reduces symptoms of upper respiratory tract infections)
- Xiao Chai Hu Tang (improves liver function in hepatitis patients)
Skullcap is also found in 38 of 210 formulations used in a Japanese system of traditional medicine called Kampo. Two of these include oregedokuto and shosaikoto [4, 1].
Flavocoxid (Limbrel) is a medical food product made from the combination of baicalin from skullcap and catechin from the bark of the Acacia catechu tree. However, its use is not recommended due to the risk of liver damage and lung inflammation (see the section below).
Side Effects & Safety
Keep in mind that the safety profile of Chinese skullcap is relatively unknown, given the lack of well-designed clinical studies. The list of side effects below is not a definite one and you should consult your doctor about other potential side effects based on your health condition and possible drug or supplement interactions.
The side effects of skullcap depend on the exact formulation used, its active compounds, and other added herbs.
Some supplements might contain toxins or impurities. It’s important to buy Chinese skullcap from a trusted manufacturer and carefully review the label to reduce the risk of unwanted effects.
Baicalein chewable tablets (100-2800 mg) were well tolerated and caused no side effects in 2 clinical trials on 105 healthy adults [102, 103].
One case study found that skullcap caused lung inflammation in a 53-year-old man [104].
There have also been multiple reports of liver damage from supplements that contain skullcap and other ingredients, but what exactly caused the damage was unclear [105, 106, 107].
Three case reports have found that a proprietary supplement used to improve joint health containing skullcap, Acacia catechu, and other nutrients, caused liver damage and lung inflammation. Skullcap was the most likely cause of the damage [108, 109, 110].
The medical food product flavocoxid (Limbrel) has also caused liver damage and lung inflammation in multiple people. Due to these reports, flavocoxid was recalled in 2018 by the FDA [44, 45, 46].
A formulation (Sho-saiko-to) containing skullcap reduced platelet count, so people with bleeding disorders may want to avoid it [111].
Due to its effects on GABA, skullcap may cause drowsiness and may affect your ability to drive and operate machinery safely [22].
Drug Interactions
Supplement/Herb/Nutrient-drug interactions can be dangerous and, in rare cases, even life-threatening. Always consult your doctor before supplementing and let them know about all drugs and supplements you are using or considering.
Drugs That Act On GABA-A Receptors
Due to its effects on GABA-A receptors, skullcap may interact with [22, 112]:
- Alcohol
- Benzodiazepines
- Nonbenzodiazepines
- Barbiturates
- Neuroactive steroids (pregnenolone and DHEA)
- Anti-seizure drugs
- Anesthetics
Statins
Baicalin can reduce the absorption of statins, so let your doctor know if you’re planning on taking skullcap in combination with these drugs [113].
Cyclosporine
Cyclosporine is a drug used to suppress the immune system of organ transplant patients to help prevent rejection. Skullcap reduced the absorption of cyclosporine in rats [114].
Blood Sugar-lowering Drugs
Skullcap and baicalin reduce blood sugar levels in rats. If it is combined with blood sugar-lowering drugs, it may further lower blood sugar [75, 76].
Drugs Processed by CYP1A2
CYP1A2 is an enzyme in the liver that processes different drugs and compounds including [115]:
- Theophylline
- Clozapine
- Tacrine
- Cancer-causing chemicals from cooked food
Baicalin blocks the activity of CYP1A2 in human liver cells and rats, possibly delaying the clearance of drugs broken down by this enzyme [115].
Reviews
The opinions expressed in this section are solely those of Chinese skullcap users, who may or may not have medical or scientific training. Their reviews do not represent the opinions of SelfHacked. SelfHacked does not endorse any specific product, service, or treatment.
Do not consider user experiences as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare providers because of something you have read on SelfHacked. We understand that reading individual, real-life experiences can be a helpful resource, but it is never a substitute for professional medical advice, diagnosis, or treatment from a qualified healthcare provider.
Skullcap was often used by people who wanted to reduce anxiety. Many people used skullcap to fight Lyme disease and other infections, as well as to relieve allergies. Others took it to reduce inflammation and generally reported improvement in joint pain.
Some users mentioned that the supplement had a sedative effect and improved their sleep. Stomach discomfort and dry skin are the side effects that have been most commonly reported.
Takeaway
Chinese skullcap is a key component of many time-tested herbal formulations used in traditional Chinese and Japanese medicine. It has strong antimicrobial effects, especially against foodborne bacteria, and can reduce gum inflammation and plaque. It may relieve allergies, protects the brain, has anti-cancer potential, and acts as a powerful antioxidant. However, very few clinical studies exist. If you decide to supplement, use caution and consider consulting a knowledgeable practitioner. There have been cases of liver toxicity and lung inflammation caused by supplements containing skullcap and baicalin, its main active component. Talk to your doctor before taking skullcap with any medication, as it may interact with drugs.