C
Unclear or conflicting scientific evidence
- Alizarin
: Limited available evidence suggests that alizarin may be of benefit in the treatment of viral infections. Additional research is needed in this area.
- Avoid if allergic or hypersensitive to alizarin or any plants in the Rubiaceae family. Alizarin may be toxic and should not be handled for long periods of time, rubbed in the eyes, or eaten. Avoid if pregnant or breastfeeding.
- Ayurveda
: Ayurveda is a form of natural medicine that originated in ancient India more than 5,000 years ago. It includes an integrated system of techniques that uses diet, herbs, exercise, meditation, yoga, and massage or bodywork to achieve optimal health on all levels. Early evidence suggests that the aqueous extract of O. sanctum leaves may benefit patients with viral encephalitis. However, human studies are needed to evaluate this approach.
- Ayurvedic herbs can interact with other herbs, foods, and drugs. A qualified healthcare professional should be consulted before taking. Ayurvedic herbs should be used cautiously because they are potent and some constituents can be potentially toxic if taken in large amounts or for a long time. Some herbs imported from India have been reported to contain high levels of toxic metals. Avoid Ayurveda with traumatic injuries, acute pain, advanced disease stages, and medical conditions that require surgery.
- Bitter orange
: Limited available human study found promising results using the oil of bitter orange for treatment of fungal infections. However, due to methodological weakness of this research, further evidence is needed to confirm these results.
- Avoid if allergic or hypersensitive to bitter orange or any members of the Rutaceae family. Avoid with heart disease, narrow-angel glaucoma, intestinal colic, or long QT interval syndrome. Avoid if taking anti-adrenergic agents, beta-blockers, QT-interval prolonging drugs, monoamine oxidase inhibitors (MAOIs), stimulants, or honey. Use cautiously with headache, hyperthyroidism (overactive thyroid), or if fair-skinned. Avoid if pregnant or breastfeeding.
- Blessed thistle
: Human research of blessed thistle as a treatment for viral infections or bacterial infections is currently lacking. Laboratory studies report that blessed thistle (and chemicals contained in blessed thistle, such as cnicin and polyacetylene) may have activity against several types of bacterial infections and no effects on some types. Early studies report no activity of blessed thistle against herpes viruses, influenza, or poliovirus. Further evidence is necessary in this area before a firm conclusion can be drawn.
- Blessed thistle is generally considered to be safe when taken by mouth in recommended doses for short periods of time, with few reported side effects such as birth defects, bleeding, breathing problems, bruising, cancer of the nose or throat, increased production of stomach acid, itching, kidney disease, liver toxicity, skin rash, stomach discomfort, stomach ulcers, and vomiting. Allergic reactions to blessed thistle including rash may occur, as well as cross-sensitivity to mugwort and Echinacea. Cross-reactivity may also occur with bitter weed, blanket flower, Chrysanthemum, coltsfoot, daisy, dandelion, dwarf sunflower, goldenrod, marigold, prairie sage, ragweed or other plants in the Asteraceae/Compositae family. Avoid if pregnant or breastfeeding.
- Cranberry
: Limited laboratory research has examined the antiviral, antifungal and antibacterial activity of cranberry. Further research is warranted in this area.
- Avoid if allergic to cranberries, blueberries, or other plants of the Vaccinium species. Sweetened cranberry juice may affect blood sugar levels. Use cautiously with a history of kidney stones. Pregnant and breastfeeding women should avoid cranberry in higher amounts than what is typically found in foods.
- DMSO
: Dimethyl sulfoxide (DMSO) is a sulfur-containing organic compound that occurs naturally in vegetables, fruits, grains, and animal products. Early research suggests that DMSO may help treat increased intracranial pressure. However, most research is vague with conflicting results and the risks may be greater than potential benefits.
- Avoid if allergic or hypersensitive to DMSO. Use caution with urinary tract cancer or liver and kidney dysfunction. Avoid if pregnant or breastfeeding.
- Garlic
: Garlic is used both medicinally and as a food spice. Preliminary research suggests that oral plus intravenous garlic may help manage symptoms of cryptococcal meningitis, a fungal infection that commonly occurs in HIV patients. Further research is needed before recommending for or against the use of garlic in the treatment of this potentially serious condition, for which other treatments are available.
- Use cautiously as garlic can cause severe burns and rash when applied to the skin of sensitive individuals.
Avoid if allergic or hypersensitive to garlic or other members of the Lilaceae
(lily) family (e.g. hyacinth, tulip, onion, leek, or chive). Avoid with a history of bleeding problems, asthma, diabetes, low blood pressure, or thyroid disorders. Stop using supplemental garlic two weeks before and immediately after dental/surgical/diagnostic procedures with bleeding risks. Avoid in supplemental doses if pregnant or breastfeeding.
- Ginseng
: Preliminary study of Xuesaitong injection (XSTI, a preparation of Panax notoginseng) reports that it may help to decrease intracranial pressure and benefit coma patients. Further study is needed to confirm these results.
- Avoid with known allergy to plants in the Araliaceae family. There has been a report of a serious life-threatening skin reaction, possibly caused by contaminants in ginseng formulations.
- Pomegranate
: In clinical study, an extract of pomegranate was shown to be as effective as a commonly used oral gel when used topically to treat candidiasis associated with denture stomatitis (mouth sores). Additional study is needed to confirm pomegranate's antifungal effects.
- Avoid if allergic or hypersensitive to pomegranate. Avoid with diarrhea or high or low blood pressure. Avoid taking pomegranate fruit husk with oil or fats to treat parasites. Pomegranate root/stem bark should only be used under the supervision of a qualified healthcare professional. Use cautiously with liver damage or liver disease. Pomegranate supplementation may be unsafe during pregnancy when taken by mouth. The bark, root, and fruit rind may cause menstruation or uterine contractions. Avoid if breastfeeding due to a lack of scientific data.
- Probiotics
: There is limited evidence that probiotic supplementation may reduce the presence of bacterial infections. More studies are needed to determine the effectiveness of probiotics for this indication.
- Probiotics are generally considered to be safe and well-tolerated. Avoid if allergic or hypersensitive to probiotics. Use cautiously if lactose intolerant. Caution is advised when using probiotics in neonates born prematurely or with immune deficiency.
- Propolis
: Propolis is a natural resin created by bees to make their hives. Propolis is made from the buds of conifer and poplar trees and combined with beeswax and other bee secretions. Animal and laboratory studies suggest that propolis may be a beneficial treatment for various types of bacterial and fungal infections. Additional research is needed to confirm these findings.
- Avoid if allergic or hypersensitive to propolis, black poplar (Populas nigra), poplar bud, bee stings, bee products, honey, or Balsam of Peru. Severe allergic reactions have been reported. There has been one report of kidney failure with the ingestion of propolis that improved upon discontinuing therapy and deteriorated with re-exposure. Avoid if pregnant or breastfeeding because of the high alcohol content in some products.
- Riboflavin
: Riboflavin (vitamin B2) is a water-soluble vitamin, which is involved in vital metabolic processes in the body, and is necessary for normal cell function, growth, and energy production. Small amounts of riboflavin are present in most animal and plant tissues. Although the exact pathogenesis of ethylmalonic encephalopathy is unknown, some research suggests that riboflavin may lead to slight improvements in motor function, cognitive behavior, and diarrhea in this disorder.
- Avoid if allergic or hypersensitive to riboflavin. Since the amount of riboflavin a human can absorb is limited, riboflavin is generally considered safe. Riboflavin is generally regarded as safe during pregnancy and breastfeeding. The U.S. Recommended Daily Allowance (RDA) for riboflavin in pregnant women is higher than for non-pregnant women, and is 1.4 milligrams daily (1.6 milligrams for breastfeeding women).
- Seaweed, kelp, bladderwrack
: Bladderwrack (Fucus vesiculosus) is a brown seaweed found along the northern coasts of the Atlantic and Pacific oceans and North and Baltic seas. Another seaweed that grows alongside bladderwrack is Ascophyllum nodosum, and
it is often combined with bladderwrack in kelp preparations. Laboratory research suggests that bladderwrack may have antifungal and antibacterial activity. However, reliable human studies to support this use are currently lacking in the available literature.
- Avoid if allergic or hypersensitive to Fucus vesiculosus or iodine. Avoid with a history of thyroid disease, bleeding, acne, kidney disease, blood clots, nerve disorders, high blood pressure, stroke, or diabetes. Avoid if pregnant or breastfeeding.
- Selenium
: Selenium is a trace mineral found in soil, water, and some foods and is essential in several metabolic pathways. Preliminary research shows that selenium may decrease elevated intracranial pressure symptoms such as headaches, nausea, vomiting, vertigo, unsteady gait, speech disorders, and seizures. More research is needed.
- Avoid if allergic or sensitive to products containing selenium. Avoid with a history of nonmelanoma skin cancer. Selenium is generally regarded as safe for pregnant or breastfeeding women. However, animal research reports that large doses of selenium may lead to birth defects.
- Sorrel
: There is currently not enough evidence on the proposed antiviral and antibacterial effects of sorrel. More research is needed.
- Avoid large doses of sorrel because there have been reports of toxicity and death. This may be because of the oxalate found in sorrel. Many sorrel tinctures contain high levels of alcohol and should be avoided when driving or operating heavy machinery. These sorrel formulations may cause nausea or vomiting when taken with the prescription drugs metronidazole (Flagyl®) or disulfiram (Antabuse®). Avoid if pregnant or breastfeeding.
- Thymus extract
: Thymus extracts for nutritional supplements are usually derived from young calves (bovine). Bovine thymus extracts are found in capsules and tablets as a dietary supplement. Preliminary evidence suggests that thymus extract has no clinical effect in patients with subacute sclerosing panencephalitis. Additional study is needed to confirm the effects of thymus extract on encephalitis.
- Avoid if allergic or hypersensitive to thymus extracts. Use bovine thymus extract supplements cautiously due to potential for exposure to the virus that causes "mad cow disease." Avoid use with an organ transplant or other forms of allografts or xenografts. Avoid if receiving immunosuppressive therapy, with thymic tumors, myasthenia gravis (neuromuscular disorder), untreated hypothyroidism, or if taking hormonal therapy. Avoid if pregnant or breastfeeding; thymic extract increases human sperm motility and progression.
- Turmeric
: Turmeric is a perennial plant native to India and Indonesia, and it is often used as a spice in cooking. Based on early research, turmeric may help treat various viral infections. However, reliable human studies are lacking in this area.
Well-designed trials are needed.
- Avoid if allergic or hypersensitive to turmeric (curcumin), yellow food colorings, or plants belonging to the Curcuma or Zingiberaceae (ginger) families. Use cautiously with a history of bleeding disorders, immune system deficiencies, liver disease, or gallstones. Use cautiously with blood thinners (e.g. warfarin). Use cautiously if pregnant or breastfeeding.
D
Fair negative scientific evidence
- Macrobiotic diet
: A macrobiotic diet has been advocated to preserve intestinal health. However, it apparently does not reduce the incidence of antibiotic resistant bacteria, nor infections caused by resistant strains in the gastrointestinal tract, compared to a diet with animal products.
- Use cautiously with cancer or other medical conditions without expert planning or supplementation. Avoid in children or adolescents without professional guidance or appropriate supplementation. Avoid in pregnant or lactating women due to potential deficiencies, unless properly supplemented.
- Probiotics
: Bacterial infection translocation, the passage of bacteria from the gut to other areas of the body where they can cause disease, is of special concern in surgery. Limited evidence suggests that supplementation with probiotics may not reduce this problem.
- Probiotics are generally considered to be safe and well-tolerated. Avoid if allergic or hypersensitive to probiotics. Use cautiously if lactose intolerant. Caution is advised when using probiotics in neonates born prematurely or with immune deficiency.