Herbal Medicines and Their Uses

Common Name	Uses	Adverse Reactions and Contraindications	Interactions	Route/Commonly Used Doses
aloe	External: Heals burns/sunburns, wounds, skin irritation; used as anti-infective agent, moisturizer. Internal: Used as laxative and for general healing.	Contact dermatitis, intestinal contractions. Avoid oral use in various GI conditions (i.e., obstruction, inflammation), ulcers, abdominal pain, menstruation, kidney conditions.	May increase risk associated with cardiac glycosides. Use with other K+-wasting drugs may add to hypokalemic effect of aloe.	PO: Capsules— 50–200 mg daily; gel— 30 ml t.i.d.; tincture (1:10, 50% alcohol) — 15–60 drops. Top: Aloe gel can be applied liberally to affected area 3–5 times daily.
anise	Common cold, cough/bronchitis, fevers, liver and gallbladder complaints, loss of appetite.	Occasional allergic reactions (skin, respiratory, and GI). Avoid if allergy to anise exists.	Excessive doses may interfere with anticoagulants, MAO inhibitors, and hormone therapy.	PO: Dried fruit— 0.5–1 g; essential oil— 50–200 ml; tea— 3 times daily.
arnica	External: Used after injuries (bruises, dislocations, contusions, muscular and joint problems). Inflammation caused by insect bites.	Prolonged use on broken skin may cause edematous dermatitis with pustular formations. Eczema (long-term use). Use of higher concentrations may cause toxic skin reactions with vesicle formation and necrosis. Avoid use on broken skin; avoid if allergy to arnica and plants in Asteraceae family exists.	None known.	Top: Typical strength is 2 g of flower heads in 100 ml of water. For poultice, dilute tincture 3–10 times with water. For mouthwash, dilute tincture 10 times with water.
black cohosh	Premenstrual symptoms, perimenopausal and postmenopausal symptoms such as hot flashes, depression, mood swings, profuse sweating, and sleep disorders.	GI discomfort (occasionally). Avoid during pregnancy and lactation.	None known.	PO: Dried root— 0.3–2 g 3 times daily; liquid extract (1:1, 90% alcohol)— 0.3–2 ml. Do not use for more than 6 mo.
brewer’s yeast	Common cold, cough/bronchitis, dyspepsia, eczema, acne, fevers, inflammation (oral, pharyngeal), loss of appetite, prevention of infections.	Allergic skin reactions may occur. Migraine headaches may be triggered in susceptible patients. GI gas may result from large doses. Avoid during pregnancy and lactation.	Concurrent use with MAO inhibitors can cause an increase in BP.	PO: 6 g of brewer’s yeast daily.
camphor	External: Pain relief for warts, cold sores, hemorrhoids, muscular aches. Antipruritic. Inflammatory conditions of the respiratory tract. Internal: Circulatory regulation disorders, catarrhal diseases of the respiratory tract (internal use is unsafe and should be avoided).	Skin irritation (local effect), contact dermatitis may occasionally occur following application of oily salves with camphor. Avoid during pregnancy and lactation. Avoid if GI conditions (infectious, inflammatory) exist.	None known.	Top: 0.1–3% 3–4 times daily for cold sores, antipruritic agent, hemorrhoids. Inhaln: 1 tbsp of camphor solution per quart of water in a hot steam vaporizer or bowl up to 3 times daily.
chamomile	External: Inflammation of skin and mucous membranes, bacterial skin diseases including oral cavity and gums. Respiratory tract inflammation and irritation. Anogenital inflammation. Internal: GI spasms and inflammatory conditions.	Contact dermatitis, severe hypersensitivity reactions, anaphylaxis, vomiting. Avoid during pregnancy and lactation.	None known.	PO: Dried flower heads— 2–8 g 3 times daily; tea— 1 cup of tea 3–4 times daily. Tea is made by steeping 3 g of flower heads in 150 ml of boiling water for 10 min. Liquid extract— 1–4 ml 3 times daily.
comfrey	External: Bruises and sprains.	No adverse reactions known. Avoid during pregnancy and lactation. Do not use on broken or abraded skin.	None known.	Top: 5–20% comfrey ointment. Use should be limited to 10 days.
dill	Dyspepsia, fever, colds, cough, bronchitis, digestive aid.	Contact dermatitis. No contraindications known.	None known.	PO: Dill seeds— 3 g; dill oil— 100–300 mg/day.
echinacea	Cold remedy, cough and bronchitis, fevers, wounds and burns, inflammation of the mouth and pharynx.	Tingling sensation on tongue, nausea, vomiting, allergic reaction, fever. Avoid if multiple sclerosis, leukoses, collagenoses, AIDS, or tuberculosis is present; avoid if hypersensitivity and cross-sensitivity exist in patients allergic to sunflower seeds and the daisy family, including ragweed; avoid during pregnancy and lactation.	May possibly interfere with immunosuppressant agents because of its immunostimulant activity.	PO: Fluid extract— 1–2 ml t.i.d.; solid form (6.5:1)— 300 mg t.i.d.. Should not be used for more than 8 weeks at a time.
eucalyptus	Cough/bronchitis, rheumatism, catarrhs of the respiratory tract.	Nausea, vomiting, and diarrhea may occur after ingestion of eucalyptus (rare). Avoid if severe liver disease, GI tract and bile duct inflammation, hypotension, kidney inflammation are present.	Induction of liver enzymes, which may increase the metabolism of other drugs.	PO: Eucalyptus oil— 300–600 mg/day. Top: Eucalyptus oil (5–20%) in vegetable oil or semisolid preparations, used for local application by diluting 30 ml of oil in 500 ml of lukewarm water.
fennel	Dyspepsias, catarrhs of the respiratory tract.	Allergic reactions (skin and respiratory tract) have been reported. Avoid during pregnancy and lactation.	None known.	PO: Dried fruit/seed— 5–7 g/day; tea— 1 cup daily. Tea is made by steeping 1–2 g of ground seed/fruit in 150 ml boiling water for 10 min and then straining.
feverfew	Prophylaxis of migraine headaches, fever, arthritis.	Dizziness, heartburn, indigestion, inflammation (lips, mouth, tongue), light-headedness, mouth ulceration, and weight gain. Allergic contact dermatitis (reported with many species of feverfew). Avoid during pregnancy and lactation.	May inhibit platelet activity (avoid use with warfarin or other anticoagulants).	PO: 50–125 mg of freeze-dried leaf per day with food.
garlic	Reduction of BP and serum cholesterol level.	GI irritation (rare), allergic reactions, alters intestinal flora. No contraindications known when used in normal amounts.	Decreases platelet aggregation (may affect warfarin and other anticoagulant therapy).	PO: One clove of fresh garlic 1–2 times daily.
ginger	Prevention and treatment of nausea and vomiting associated with motion sickness. Prevention of postoperative nausea and vomiting. May be used for dyspepsia, flatulence, and relief of joint pain in rheumatoid arthritis.	Minor heartburn, dermatitis. Avoid during pregnancy and lactation (if using amounts larger than those typically found in food); avoid if gallstones exist. Use cautiously in patients with increased risk of bleeding or diabetes.	Natural Product–Drug: may theoretically increase risk of bleeding when used with anticoagulants and antiplatelet agents. Natural Product–Natural Product: may theoretically increase risk of bleeding when used with other herbs that have anticoagulant or antiplatelet activities.	PO: 1000 mg ginger taken 3–60 min before travel for motion sickness or before surgery.
ginkgo	Symptomatic relief of organic brain dysfunction (dementia syndromes, short-term memory deficits, inability to concentrate, depression), intermittent claudication, vertigo and tinnitus of vascular origin.	Dizziness, headache, upset stomach, allergic skin reaction, palpitations. Avoid if hypersensitivity exists; avoid during pregnancy and lactation.	Natural Product–Drug: theoretically may potentiate effects of antiplatelet agents and MAO inhibitors. Natural Product–Natural Product: may increase risk of bleeding when used with other herbs with antiplatelet effects (some include angelica, arnica, chamomile, feverfew, garlic, ginger, and licorice).	PO: native dry extract— 120–240 mg in 2 or 3 doses for organic brain syndromes; 120–160 mg in 2 or 3 doses for intermittent claudication, vertigo, and tinnitus.
ginseng	Improving physical stamina, general tonic to energize during times of fatigue and inability to concentrate, sedative, sleep aid, antidepressant, diabetes.	Depression, dizziness, headaches, insomnia, hypertension, tachycardia, amenorrhea, vaginal bleeding, skin eruptions, estrogen-like effects, mastalgia, Stevens-Johnson syndrome. Avoid during pregnancy and lactation; avoid if manic-depressive disorders or psychosis exists.	Natural Product–Food: may potentiate effects of caffeine in coffee or tea. Natural Product–Drug: may decrease anticoagulant activity of warfarin. Avoid concomitant use with warfarin, heparin, aspirin, and NSAIDs. May interfere with phenelzine treatment and cause headache, tremulousness, and manic episodes. May potentiate the toxic effects of corticosteroids. Natural Product–Natural Product: may increase risk of bleeding when used with herbs that have antiplatelet or anticoagulant activities.	PO: capsule— 200–600 mg/day; root powder— 0.6–3 g 1–3 times daily.
goldenseal	Infections of the mucous membranes (bacterial and fungal), conjunctivitis, and GI infections associated with diarrhea, cirrhosis, gallbladder inflammation, and cancer. Topically used to treat eczema, acne, itching.	CNS stimulant, hallucinations, occasionally delirium, nausea, vomiting, constipation, ulceration (vaginal use), may affect production of B vitamins in colon. Avoid during pregnancy and lactation; avoid if hypertension exists.	Natural Product–Drug: May theoretically interfere with antacids, sucralfate, and H2 antagonists. May interfere with antihypertensive agents and anticoagulants. May have additive effects when used concurrently with other drugs with sedative properties. Natural Product–Natural Product: concurrent use with herbs that have sedative properties may potentiate sedative effects.	PO: dried root and rhizone— 0.5–1 g t.i.d.; liquid extract— (1:1 in 60% ethanol)— 0.3–1 ml t.i.d.; tincture— (1:10 in 60% ethanol)— 2–4 ml t.i.d. Top: used as mouthwash 3–4 times daily.
hawthorn	Hypertension, mild to moderate CHF, angina, spasmolytic, sedative.	Agitation, dizziness, headache, sedation (high dose), sleeplessness, hypotension (high dose), palpitations, nausea. Avoid during pregnancy.	Natural Product–Drug: increases vitamin C utilization in body, may inhibit metabolism of ACE inhibitor, potentiates effect of cardiac glycosides, concurrent use with other coronary vasodilators (theophylline, caffeine, epinephrine) may potentiate vasodilatory effects, may have additive CNS depressant effect when used with other CNS depressants. Natural Product–Natural Product: additive effect with other cardiac glycoside–containing herbs (digitalis leaf, black hellebore, oleander leaf).	PO: Hawthorn fluid extract (1:1 in 25% alcohol)— 0.5–1 ml t.i.d.; hawthorn fruit tincture (1:5 in 45% alcohol)— 1–2 ml t.i.d.; dried hawthorn berries— 300–1000 mg t.i.d.
kava-kava	Anxiety, stress, restlessness, insomnia, mild muscle aches and pains.	Dizziness, headache, sedation, sensory disturbances, pupil dilation, visual accommodation disorders, gastrointestinal complaints, allergic skin reactions, yellow discoloration of skin, pellagroid dermopathy, weight loss, ataxia, muscle weakness. Avoid during pregnancy and lactation; avoid if endogenous depression exists. Do not give to children under 12 yr of age.	Natural Product–Drug: additive effect when used with alprazolam. Potentiates effect of CNS depressants (ethanol, barbiturates, benzodiazepines), has decreased the effectiveness of levodopa in a few cases. May have additive effects with antiplatelet agents and MAO inhibitors. Natural Product–Natural Product: May have additive sedative effects when used with other herbs with sedative properties.	PO: dried kava root extract— 100–250 mg for antianxiety; kavalactones— 180–210 mg for insomnia.
ma-huang	Asthma, hay fever, colds, weight-loss aid.	Increased BP and heart rate and cardiac arrhythmias, insomnia, motor restlessness, headaches, nausea, vomiting, anxiety. Avoid during pregnancy and lactation. Avoid if heart disease, hypertension, diabetes, hyperthyroidism, or BPH is present.	Potentiates sympathomimetic effects of antihypertensives, antidepressants, MAO inhibitors, and caffeine.	PO: Ephedra— 15–30 mg 2–3 times daily; crude herb— 500–1000 mg 2–3 times daily.
milk thistle	Cirrhosis, chronic hepatitis, gallstones, psoriasis.	Mild laxative, mild allergic reaction. Avoid during pregnancy and lactation.	None known.	PO: Extract (70%)— 200–400; dried fruit/seed— 12–15 g/day; tea— 3–4 times daily 30 min before meals. Tea is prepared by steeping and 3–5 g of crushed fruit/seed in 150 ml of boiling water for 10 min and then straining.
mugwort	GI ailments (colic, diarrhea, constipation), worm infestations, persistent vomiting, hysteria, epilepsy, menstrual problems and irregular periods; as a sedative.	Allergic reactions. Avoid during pregnancy and lactation.	None known.	PO: Tincture— 5 ml 30 min before bedtime or 1–4 ml up to 3 times daily.
nettle	Urinary tract infections, kidney and bladder stones. Supportive therapy for rheumatic ailments.	Allergic reactions (rare). Avoid during pregnancy and lactation.	None known.	PO: Tea— 1 cup up to 3 times daily with adequate fluid intake. Tea is made by steeping 1.5–5 g of nettle in 150 ml of boiling water for 10 min and then straining. Dried extract (7:1)— 770 mg twice daily; liquid extract (1:1, 25% alcohol)— 3–4 ml 3 times daily. Top: Tincture (1:10) for external use.
oak bark	External: Inflammatory skin disease. Internal: diarrhea (nonspecific, acute), mild inflammation of oral and pharyngeal regions and genital and anal areas.	GI disturbances, kidney damage, liver necrosis. Avoid during pregnancy and lactation. Avoid oak bark baths if weeping eczema, large areas of skin damage, febrile or infectious disease, cardiac insufficiency is present.	May reduce or inhibit the absorption of alkaloids and other alkaline drugs.	PO: For diarrhea, 1 cup of tea up to 3 times daily for 3–4 days. Tea is made by steeping 1 g coarsely ground bark in 150 ml of boiling water and then straining. Top: For rinses, compresses, gargles, use 20 g bark in 1 liter of water. For baths, use 5 g bark in 1 liter of water and add to bath water. Topical use should be limited to 2–3 weeks.
pennyroyal	External: Skin diseases. Internal: Digestive disorders, liver and gallbladder disorders, gout, colds, and increased urinary frequency.	Abortifacent in high doses. Hepatotoxicity (use not recommended because of hepatoxicity). Avoid during pregnancy and lactation.	None known.	Use not recommended because of toxicity.
peppermint	Colds, coughs, inflammation of mouth and pharynx, GI cramps and as an antiflatulent and antipyretic agent. The oil is used topically for myalgias, toothaches, pruritus, urticaria, and as an anti-infective agent.	Heartburn when taken orally. Allergic reactions (headache and flushing). External use may cause skin irritation and contact dermatitis. In small children and babies, the oil may cause bronchial spasms and collapse when applied to their facial, nasal, or chest areas. Avoid during pregnancy and lactation. Avoid use of oil on infants/small children. Avoid if hypersensitivity to peppermint exists. Avoid if bile duct obstruction, severe liver disease, or gallbladder inflammation is present.	Gastric acid–blocking drugs.	PO: Peppermint oil— 0.2–0.4 ml 3 times daily in diluted preparation; capsules— 1–2 capsules 3 times daily (0.2 ml/capsule). Top: 5–20% peppermint oil in oily preparations, 5–10% in aqueous/ethanol preparations, 1–5% in nasal preparations. To apply, rub small amount on affected skin areas. Inhaln: 3–4 drops of oil placed in hot water and inhaled. Inhalation contraindicated in children.
psyllium	Constipation, diarrhea, lowering serum cholesterol	Flatulence, abdominal distention, esophageal/bowel obstruction if not taken with water/fluid. Allergic reactions. Avoid if fecal impaction, GI tract obstruction or narrowing is present.	Interferes with absorption of other drugs taken simultaneously.	PO: 3.5 g 1–3 times daily of the seed husk taken with adequate fluids.
Saint John's wort	Management of mild to moderate depression. Externally used for inflammation of the skin, blunt injuries, wounds, and burns.	Dizziness, restlessness, sleep disturbances, fatigue, hypertension, GI side effects, abdominal pain, bloating, constipation, dry mouth, feeling of fullness, flatulence, nausea, vomiting, allergic skin reactions, phototoxicity, photodermatitis. Avoid during pregnancy and lactation. Do not give to children.	Concurrent use with alcohol or other antidepressants may increase the risk of adverse reactions. Concurrent use with indinavir may significantly reduce blood concentrations of indinavir.	PO: hypericum extract— 300 mg t.i.d. for depression. Top: hypericin— 0.2–1 mg daily.
saw palmetto	Urination problems in BPH, irritable bladder.	Headaches, stomach problems (rare). Avoid during pregnancy and lactation; avoid if breast cancer exists.	Oral contraceptives and hormone therapy (possible).	PO: Dried berry— 0.5–1 g of dried berry three times daily; tea— 1 cup of tea 3 times daily. Tea is made by steeping 0.5–1 g of dried berry in 150 ml of boiling water for 10 min and then straining. Saw palmetto extracts with 80–90% fatty acids— 160 mg twice daily.
spruce	Colds, cough, bronchitis, fevers, inflammation of the mouth and pharynx.	May worsen bronchial spasms. Avoid during pregnancy and lactation. Avoid if asthma or whooping cough exists. Avoid baths with spruce if extensive skin damage, acute skin diseases, fevers, infectious diseases, or cardiac insufficiency is present.	None known.	PO: Fresh shoots— 5–6 g/per day. Essential oil— given as 4 drops in water or with sugar 3 times daily. Top: 200–300 g of shoots boiled in 1 liter of water; steep for 5 min, strain, and add to full bath. Inhaln: Inhale 2 g of oil in hot water several times daily.
uva-ursi	Urinary tract infections.	Nausea, vomiting, GI upset, hepatotoxicity, high toxic doses (30–100 g of uva-ursi) can cause death. Avoid during pregnancy and lactation. Avoid if kidney disorders or GI irritable disorders exist. Do not give to children.	Use with urine-acidifying drugs may reduce the efficacy of uva-ursi.	PO: 1 cup of tea up to 4 times daily. Tea is made by steeping 3 g of dried leaf in 150 ml cold water for 12–24 hr and then straining. This herb should not be used for more than 1 week at a time, no more than 5 times a year.
valerian	Restlessness, sleeping disorders due to nervous conditions.	Morning drowsiness, headaches, excitability, insomnia. Avoid during pregnancy and lactation.	Use with alcohol and other sedatives may potentiate sedative effects.	PO: Extract (0.8% valeric acid) — 150–300 mg 30 min before bedtime. Tea— 1 cup 1–3 times daily. Tea is made by steeping 2–3 g of root in 150 ml of boiling water for 10 min and then straining.
woodruff	Nervousness, sleeplessness, hysteria, cardiac irregularity.	Headache, stupor (high doses). Liver damage (reversible) may occur with long-term use in susceptible patients. Avoid during pregnancy and lactation.	None known.	PO: 1 cup of tea once a day, shortly before bedtime. Tea is made with 2 teaspoonfuls (1.8 g) in one glass of water.

BPH: benign prostatic hyperplasia; Inhaln: Inhalation; PO: by mouth; PSA: prostate-specific antigen; Top: topical.
* NOTE : Instruct patient to consult health care professional before taking any prescription or OTC medications concurrently with any of these herbal products. The purity, safety, and effectiveness of many herbal remedies remain untested and unproven.
SOURCE: Deglin, JH and Vallerand, AH: Davis's Drug Guide for Nurses (11th ed.), F.A. Davis, Philadelphia, 2009.