Glossary of Herbal Supplements - Herbs - 2

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Glossary of Herbal Supplements
Herbs F-M
Herbs N-Z
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F

Fennel (Foeniculum vulgare)

Fennel is used in cooking and is generally safe.  As a supplement, fennel is commonly used for upset stomachs, but research isn’t strongly conclusive.  Research supports the use of fennel for colicky babies.  Fennel seed and oil are the part of the plant used for medicinal purposes.

Safety Information: Fennel is generally safe.  Allergic reactions are common.  Pregnant women should not supplement with fennel.  Seizures have been associated with fennel oil use.  Avoid if history of seizures.  Diabetics should use cautiously fennel that is prepared in syrup or honey.  Probably safe for children if taken in small doses.  Safety for pregnant women is unknown.

Interactions: Do not take within 2 hours of taking Ciprofloxacin.

Lab Notes: May alter liver function tests and blood-clotting times.  May lower blood pressure, cholesterol and blood glucose levels.

Feverfew (Tanacetum parthenium)

The leaf of this plant is purported to have a number of uses.  Research is mixed supporting the use of feverfew for prevention of migraine headaches.  May have pain-relieving properties, but evidence for this is not strong.

Safety Information: Most side effects were mild.  Inflammation of the lips, mouth, gum, and throat were the most common.  Gastrointestinal distress and sun sensitivity were reported.  There were withdrawal symptoms for those who stopped feverfew after long-term use.  These were headache, anxiety, insomnia, and muscle and joint discomfort.  Those with platelet or clotting problems should use cautiously.  Safety of feverfew for children, pregnant and nursing mothers is not established.

Interactions: May interact with aspirin, NSAIDs, coumadin, and other anticoagulant drugs.

Lab Notes: May interfere with coagulation labs, such as PT and INR.

Fish Oil

The primary groups of essential fatty acids are omega-3s and omega-6s.  Fish oils are high in omega-3s.  Fish oils have attracted a great deal of interest and research.  As part of one’s diet, the evidence is strongly in favor of fish oil’s ability to lower triglycerides and protect against the occurrence of sudden heart attack.  However, fish oil supplementation had failed to point to the same conclusions.  Fish oils may help with many other conditions, such as rheumatoid arthritis, depression, cognition, inflammation, and protection from cyclosporine toxicity in organ transplant patients.  Much more research will need to be conducted in order to support these and the many other claims about the value of fish oils.  Research has found that fish oils may raise both LDL and HDL cholesterol, making it an impractical choice for high cholesterol patients.  Research also suggests that fish oil does not prevent organ transplant rejection.

Safety Information: Most common reports were a fishy aftertaste, rash, and gastrointestinal complaints: indigestion, acid reflux, burping, bloating, loose stools and diarrhea.  Use cautiously if diagnosed with bi-polar disease, diabetes, low blood pressure, or have reduced blood-clotting ability.  Use of over 3 grams daily of fish oil may interfere with blood clotting.  Fish can be high in mercury and other contaminants.  Safety of omega-3 fatty acids has not been established for infants, children, pregnant and breastfeeding women.  However, these groups should avoid fish as a source of omega-3s because of the high risk of mercury ingestion.

Interactions: May raise vitamins A and D, both of which can be toxic in high amounts.

Lab Notes: May raise blood glucose levels, LDL/HDL cholesterol and increase blood-clotting times.

Note: Fish oil has many kinds of omega-3 fatty acids.  DHA and EPA are most abundant in cold-water fish, especially salmon.  DHA and EPA are also found in nuts, seeds, soy, and in trace amounts in dark green leafy vegetables.  It is suggested to start with low amounts of fish oil, gradually increasing the dose.  Fish oils should be taken with meals and a full glass of water.

Flaxseed and Flaxseed Oil (Linum usitatissimum)

Flaxseed is high in fiber and used as a laxative.  It is high in an essential fatty acid, top-linolenic acid.  The oil has no fiber.  Other

Other purported uses include cancer prevention, high cholesterol, menopausal symptoms, heart disease, diabetes and high blood pressure, but data is weak.

Safety Information: Most common side effects are increased bowel movements and flatulence. Constipation may occur if flaxseed is taken with insufficient water. Long-term effects are not known. Use cautiously if taking blood-thinning medications. Men with a history of prostate cancer should avoid flaxseed.

Raw flaxseed and unripe pods may be poisonous. Overdose of flaxseed may cause breathing difficulties, weakness, seizures, paralysis and difficulty walking. Avoid flaxseed use if bipolar. Because of its laxative effects, avoid when there are pre-existing bowel problems. Large amounts of flaxseed may cause bowel obstruction. Take the seed with large amounts of water, at least a 1:10 ratio. Diabetics should use cautiously. People with hormone sensitive conditions or cancers should avoid flaxseed. Pregnant and nursing women should probably avoid flaxseed. Not enough evidence to recommend safe use for children.

Interactions: Flaxseed may interfere with drug absorption. Do not take any drugs, herbs, or other supplements one hour before or two hours after taking flaxseed. May interfere with mood stabilizing medications. Women taking tamoxifen, birth control pills and other hormones may want to avoid. Use cautiously if taking blood-thinning medications.

Lab Notes: May alter blood-clotting tests. May lower blood pressure. May increase blood sugar levels. Flaxseed increased the red blood cell count in animal studies.

Note: Flaxseed breaks down when cooked or exposed to high heat. Flaxseed needs careful storage. Dry flaxseed may be stored in a cool dry location for up to one year. Flaxseed oil should be kept refrigerated in a dark opaque bottle.

G

Garlic (Allium sativum)

Garlic has a long history and may have many health benefits. There is quite a bit of garlic research, but to date the studies don’t substantiate most of the claims. Garlic may lower triglycerides and low-density lipoproteins (“bad” cholesterol).

Attention for Liver Disease: May decrease clotting ability.

Safety Information: Garlic is probably safe at recommended doses. Garlic may cause bad breath, body odor, gastric complaints and allergies. Garlic may increase bleeding risk. Avoid topical application and ingesting large amounts. A myocardial infarction was reported in a 23 year-old man who took excessive amounts of garlic. May be safe for children, pregnant or nursing mothers, but may alter the flavor of breast milk.

Interactions: Patients taking cyclosporine should use cautiously. One report of garlic’s interference with the effectiveness of saquinavir, a drug used to treat HIV infection. Two reports of gastrointestinal distress by people taking garlic and HIV drug, ritonavir. May interact with any cytochrome p-450 metabolized substances (see About Cytochrome P-450 below). May interact with fish oils, EPA, pycnogenol, NSAIDs, protease inhibitors, hypoglycemic, anti-hypertensive, thyroid, lipid-lowering, and anticoagulant drugs.

Lab Notes: May cause abnormal insulin and thyroid levels, increase clotting times, and lower cholesterol, blood sugar and blood pressure.

Note: Fresh or odorless enteric-coated garlic are probably the best forms to use.

Ginger (Zingiber officinale)

Ginger is a good example of how a plant can be used as a food, spice or medicine. Ginger has a long history. Research supports the efficacy of ginger for pregnancy-related nausea and vomiting. The evidence is weak regarding the use of ginger for nausea related to chemotherapy, surgery or motion sickness.

Safety Information: Most common side effects are gastrointestinal complaints. Central nervous system depression and arrhythmias have occurred following overdose. Likely to be safe for pregnant and nursing women if used in moderate doses for no more than five consecutive days. Safety not established for children.

Interactions: Use cautiously if taking anticoagulants, H2-blockers, antihypertensives or blood sugar lowering medications. Use cautiously with high doses of calcium.

Lab Notes: May alter coagulation and blood glucose levels.

Note: Should not be used at excessive doses or for more than five consecutive days if used for morning sickness.

Ginkgo Biloba (Ginkgo biloba)

This herb has been used for centuries and has been studied extensively. Ginkgo is purported to have anticoagulant properties. Ginkgo is used for many conditions, such as leg pain from clogged arteries, dementia and cognitive decline, and circulatory problems. Evidence is promising but insufficient and conflicting to draw firm conclusions.

Safety Information: Generally, ginkgo has a good safety record when used as recommended. Ginkgo fruit pulp and seeds are toxic: 70 reports of toxicity, including seizures, loss of consciousness, and death. May increase bleeding risk. Use cautiously in patients with bleeding or blood clotting disorders, and/or decreased clotting ability, such as those taking NSAIDs or anticoagulants. Use cautiously if diabetic. May lower seizure threshold. Reports of dermatological, neurological, cardiovascular and gastrointestinal side effects. Theoretically may reduce male and female fertility. Unsafe for infants. No safety data for children. Not recommended for pregnant or nursing women.

Interactions: May interact with any cytochrome p-450 metabolized substances (see About Cytochrome P-450 below). Ginkgo is known to interact with a very long list of drugs, herbs and supplements, such as many types of antidepressants, antipsychotics, anticoagulants, insulin, erectile dysfunction drugs and Yohimbe. May increase colchicine levels.

Lab Notes: May alter coagulation labs, such as PT and INR. May increase concentrations of insulin and C-peptides in the blood.

Note: Never take high doses or extracts with gingkolic acid. Only use standardized ginkgo.

Ginseng (many varieties)

This herb has been widely studied and has earned a prominent reputation in Chinese medicine. May provide benefits for certain cardiac, immune, and high blood sugar conditions. Purported to improve mental ability and fatigue along with many other uses but no scientific evidence for this. Small studies show possible benefit for those with liver disease.

Safety Information: Contraindicated for those with hypertension. Multiple side effects and warnings, including cardiac, bleeding, and manic symptoms. May cause menstrual irregularities and breast tenderness. Not enough evidence to recommend safe use for children. Pregnant and nursing women and those with history of breast or uterine cancer should avoid ginseng.

Interactions: May interact with any cytochrome p-450 metabolized substances (see About Cytochrome P-450 below). May interact with many drugs including warfarin, aspirin, ibuprofen, naproxen, MAO inhibitors, calcium channel blockers, digoxin, and opioids. Should not be used with other stimulants, including excessive caffeine.

Lab Notes: May alter blood pressure, blood glucose levels and liver function tests. May alter coagulation labs, such as PT and INR.

Note: Should not be taken continuously. If taken continuously for 2 weeks, discontinue for 2 weeks before restarting. Andrew Weil, MD suggests using American ginseng since the Asian variety is associated with insomnia, irritability, and increase blood pressure. He also states that “real ginseng” contains ginsenosides.

Glucosamine

This supplement has been well-researched and consistently shows improvement for osteoarthritis, particular for knee pain. Unfortunately the research is inconsistent. Glucosamine is often combined with chondroitin but can be taken alone. Made from corn or shellfish.

Safety Information: Avoid or take corn version if allergic to shellfish. Side effects include gastric discomfort, headache, itching, leg pain, edema, drowsiness, insomnia, sun sensitivity, and toughening of the nails. Increased blood pressure, heart rate and palpitations also reported. May lower blood sugar levels. Use cautiously if there is history of asthma or diabetes. Cataracts were reported in animal studies, but not in humans. The safety for children is not established. Pregnant and breastfeeding women should avoid.

Interactions: May interact with diuretics, insulin and recombinant erythropoietin.

Lab Notes: May lower blood glucose levels and increase blood pressure.

Note: Chondroitin may take over 3 months before there are noticeable benefits.

Green Tea (Camellia sinensis)

Green tea has been used for centuries. It is a source of antioxidants. It also contains caffeine and tannins. It is purported to prevent cancer and to help many medical conditions, but there is no clear evidence to support or dispute this. Caffeine may help to relieve headaches and fatigue.

Safety Information: The majority of warnings are associated with green tea’s caffeine content. Caffeine acts as a stimulant and diuretic. The primary complaints were frequent urination, nervousness, insomnia, and gastric discomfort. Anyone needing to avoid or reduce caffeine should use decaffeinated green tea. This includes those with anxiety, high blood pressure, cardiac, kidney and hyperthyroid disease. May delay blood-clotting ability, especially if high amounts are used. May stimulate stomach acid production. Classified by the FDA as “generally regarded as safe.” Pregnant and breastfeeding women should avoid caffeine. High caffeine use during pregnancy is associated with risk of birth defects and SIDS. Caffeine can cause sleeplessness in infants. Safety in children is not established.

Interactions: May interact with MAO-inhibitors, codeine, stimulants and other herbs. Can reduce iron’s bioavailability, so do not drink green tea two hours before or 4 hours after taking iron supplementation.

Lab Notes: May increase blood-clotting times and blood glucose levels. May lower electrolyte levels.

Note: One cup of average strength green tea has approximately 50 mg of caffeine.

H

Hoodia (Hoodia gordonii)

This succulent plant has attracted a great deal of interest because of its supposed weight-loss properties. However, none of this is evidence-based. One never-published “study” of 18 obese people supposedly showed weight loss, but this research was not well-constructed or scientifically reviewed. The biggest problem with Hoodia is that it is scarce and much of what is being sold to consumers actually has little or no hoodia.

Safety Information: Not known.

Interactions: None known.

Lab Notes: None known.

L

Licorice Root (Glycyrrhiza glabra and G. uralensis)

Glycyrrhizin is the primary active substance in licorice root. This root has been used for centuries in many parts of the world. An NCCAM review of randomized, controlled studies reports possible benefits for improvement of liver tissue for hepatitis patients and may reduce HCV complications for non-responders to interferon treatment. Thought to prevent liver cancer in those with HCV, although this has not been proven. Glycyrrhizin may lower liver enzymes but does not seem to lower HCV viral loads. Licorice root may prevent ulcers related to aspirin or NSAID use. Purported to stimulate the adrenal glands, but the evidence is insufficient.

Safety Information: Likely safe when used in moderate amounts. Prolonged or excessive use can lead to potentially serious side effects including, potassium depletion, high blood pressure, lethargy, hypertensive encephalopathy, sodium and water retention and swelling. Should be avoided by anyone with kidney disease, diabetes, and hormone-sensitive cancer. Other potential side effects include nausea, vomiting, headache, and decreased libido in men. Should be avoided by pregnant and nursing women. Safety in children is not established.

Interactions: May interact with diuretics, digitalis, antiarrhythmics, corticosteroids, heart and blood pressure medications, MAO inhibitors, antidiabetes drugs, anti-rejection agents, hormones, birth-control pills and anti-cancer drugs such as tamoxifen.

Lab Notes: May decrease liver enzymes, potassium and testosterone levels. May increase sodium levels and blood pressure. May alter blood glucose levels.

Note: Licorice root should not be used for more than 4 to 6 weeks. Prolonged use increases risk of serious side effects. Some sources recommend use of deglycyrrhizanated (DGL), since glycyrrhizic acid may be responsible for most of the side effects. However, some argue that this reduces overall effectiveness.

M

Maitake (Grifola frondosa)

Maitake is a mushroom, making it both a food and a supplement. Has been found to be safe as a food source. Very little is known about its safety and efficacy as a higher dose supplement. Some purported but unproven uses include immune stimulation, antihypertensive, antidiabetes, cancer, HIV, hepatitis and fatigue management.

Attention for Liver Disease: None known. If maitake stimulates the immune system, then theoretically, should be avoided by those with autoimmune hepatitis, primary biliary cirrhosis or other autoimmune diseases; those taking immune suppressants, such as steroids and anti-rejection drugs for liver transplantation; and those using interferon.

Safety Information: Maitake may lower blood pressure and blood glucose levels. Safety for children, pregnant or breastfeeding women has not been established.

Interactions: Use cautiously if taking medications to treat blood pressure or blood glucose levels. Use cautiously if taking other herbs or supplements that are known to also lower blood pressure or blood glucose levels.

Lab Notes: May lower blood pressure and blood glucose tests.

Melatonin (N-acetyl-methoxytryptamine)

Melatonin is a hormone produced by the body’s pineal gland. Melatonin responds to the presence and absence of light, which affect sleep-wake cycles. As a supplement, melatonin is not well absorbed by the body and is rapidly metabolized by the liver. Research supports the efficacy of melatonin for jet lag. May help with other sleep-related problems. Less is known about many other purported uses, such as Alzheimer’s, ADHD, cancer, etc.

Attention for Liver Disease: Melatonin has been linked to autoimmune hepatitis.

Safety Information: Melatonin has few side effects when used short-term. Common side effects include fatigue, dizziness, irritability, headache, mood changes, disorientation, eye problems and gastrointestinal complaints. There may be an increased risk of blood clotting, particularly those taking blood-thinning drugs. Use cautiously if there is a history of seizures, major psychiatric problems, heart disease, blood pressure problems, and diabetes. Hormonal side effects have been reported, so use cautiously with any condition or medication that may be influenced by hormones. Long-term effects are unknown. Pregnant and nursing women should avoid melatonin. Not enough evidence to recommend safe use for children.

Interactions: May interact with any cytochrome p-450 metabolized substances (see About Cytochrome P-450 below). Use cautiously with alcohol, caffeine, blood-thinning, anti-depressant, anti-seizure, blood pressure, diabetic and any sedating medications and supplements. Use cautiously if taking Nifedipine or Fluvoxamine.

Lab Notes: May affect blood pressure, blood sugar levels and blood-clotting tests.

Note: Taking melatonin too early in the daytime may cause daytime drowsiness.

Milk Thistle (Silybum marianum)

A great deal of research has been conducted using this herb for a variety of liver diseases, although little specifically targeting HCV. The evidence is promising regarding the use of milk thistle for liver inflammation and possibly cirrhosis. Three ingredients in milk thistle are of scientific interest because of their potential therapeutic value and capacity to protect the liver. These ingredients are silibinin, silychristin, and silydianin, collectively known as silymarin.

Safety Information: If used as recommended, milk thistle is generally safe. Reported side effects are mild laxative, gastric complaints, itching and lowered blood sugar levels. Safety has not been established for children, pregnant or nursing mothers.

Interactions: May interact with any cytochrome p-450 metabolized substances (see About Cytochrome P-450 below). Silymarin has the potential to interact with many drugs, herbs and dietary supplements. A few are hormones, methadone, antibiotics, anti-seizure, antidepressants, antipsychotics, antihistamines, organ transplant-rejection, cardiac, lipid-lowering drugs and sleeping pills.

Lab Notes: May alter liver function tests and blood sugar levels.