Herbal & Drug Interactions
This list below provides common herbal and drug interactions.
Please note that the prescription drug listings are not all-inclusive; drugs listed
are common examples.
If you are currently on any of the following drugs below, you need to exercise
extreme caution if you are using any of the herbal or
nutraceutical's that are listed below.
For example, if you are currently on a statin drug (such as: lipitor) you should
not be taking red yeast rice, the reason for this is that red yeast
rice is also very effective for lowering cholesterol levels.
By taking both a statin drug and red yeast rice, this in most cases will lower your
cholesterol levels to much. This would be similar as if your medical
physician was giving you twice the dosage of the statin drug.
The extensive background, qualifications and education that Dr. Hardy has undergone, as both a Certified
Clinical Nutritionist (CCN) and Diplomate of the American Clinical Board of Nutrition (DACBN) Dr. Hardy can
assist you in this area
of health care.
If you would like to use an integrative approach of using both
medication and herbal / nutraceutical's, Dr. Hardy can help to monitor you
with blood work to make sure you are not getting your levels in an
unsafe range.
If you prefer to use the herbal or nutraceutical approach, Dr. Hardy will monitor
your results and blood tests if needed, to see if this option is safe and
working for you.
Remedies: Nutritional support, retained water, Cholesterol, menopause,
addiction,
urinary, bowel problems
|
Herb |
Drug Class |
Type of Interaction |
Alfalfa (Medicago sativa) - Leaf |
Anticoagulants2,4,9
e.g. Warfarin3 |
Interact
Reduced drug action due to Vitamin K content in alfalfa |
|
Hormone replacement therapy2,4,9 |
Interact |
|
Oral contraceptive2,4,9 |
Interact |
|
Xenobiotics3 |
Increases rate of metabolism |
Remedies:
Immune system, Cancer, Heartburn, Arthritis
|
Aloe Vera - (A. vera) Latex Powder |
All drugs12 |
Aloe latex will bind all drugs |
|
Antiarrythmic agents5,11,12
e.g. Quinidine |
Interact |
|
Cardiac glycosides2,3,5,11,12 e.g. Digoxin5 |
Increases toxicity. Increases effect due to potassium loss, hypokalemia |
|
Cortico-adrenal steroids5,11 |
Increases potassium deficiency |
|
Diuretics3 e.g. Loop diuretics5
e.g. Thiazide diuretics5,11 |
Increases potassium loss
Interact
Interact |
|
Laxative, stimulant20 |
Increases diarrhea, abdominal pain and fluid loss |
|
Oral drugs3,11 |
Decreases absorption of drug due to reduction in bowel transit time |
|
Glyburide4 |
Increases hypoglycemic effect |
Aloe Vera - Gel or Juice |
Glibenclamide3,4 |
Increases hypoglycemic effect |
Remedies: Digestion, Infection, Respiratory
problems and infections, Menopause
|
Anise or Aniseed (Pimpinella anisum) - Seed |
Anticoagulants9 |
Excessive doses of Anise may interact with anticoagulants |
|
Hormone Replacement Therapy9 |
Excessive doses of Anise may interact with HRT |
|
Iron5 |
Enhances iron absorption across the intestinal mucosa |
|
Oral contraceptive9 |
Excessive doses of Anise may interact |
|
MAOIs9 |
Excessive doses of Anise may interact with MAOI therapy |
Remedies: Alzheimer's, Common cold, Sore
throat, Chemotherapy support
|
Astragalus (Astragalus membranceus) - Root |
Acycloir20 |
Drugs incompatible with herb |
|
Aldesleukin20 |
Astragalus with low dose Aldesleukin resulted in a 10-fold potentiation of
Aldesleukin's tumor cell killing activity with decreased side effects |
|
Anticoagulants/Antiplatelet20 |
Increases risk of bleeding |
Remedies: Digestion, Stomach cramps,
Vomiting, Constipation, Anxiety, Headaches
|
Basil (Ocimum basilicum) - Leaf |
Antidiabetic agents5 |
May enhance hypoglycemic effects |
|
Insulin5 |
May enhance hypoglycemic effects |
|
Sulfonylureas5 |
May enhance hypoglycemic effects |
Remedies: Stomach problems,
Rheumatism
|
Bay (Laurus nobilis) - Leaf |
Insulin5 |
Herb enhances hypoglycemic actions - may increase insulin's effect more than three
fold5 |
Remedies: Arthritis, Urinary problems,
Diarrhea, Bronchitis, Fever, Hemorrhoids
|
Bearberry Uva Ursi (Arctostaphylos uva-ursi) - Leaf |
Drugs that acidify the urine3,4,5,7
e.g. Vita. C (Absorbic Acid) |
May decrease the urinary antimicrobial action |
|
Drugs known to interact with hydroquinone2 |
Theoretically, caution should be exercised |
|
Diuretics5 |
Enhances electrolyte loss |
Remedies: Prevent cataracts, Enhance night
vision, Blood circulation, Diarrhea,
Liver & stomach problems
|
Bee Pollen |
Antidiabetic agents5
Hypoglycemic agents5
Insulin5 |
Interact - May promote hyperglycemia |
Bilberry (Vaccinium myrtillus) - Fruit |
Anticoagulants5
e.g. Warfarin4,20 |
Increases risk of bleeding
Increases bleeding time |
|
ASA4 |
Interact |
Bilberry - Leaves |
Insulin3 |
May cause hypoglycemia |
Remedies: Lessens inflammation, Diuretic,
Joint pain, Urinary tract infections
|
Birch (Betula) - Leaf |
None reported5,10 |
|
Remedies: PMS, Menstruation problems, Hot
flashes
|
Black Cohosh (Actaea racemosa) - Root |
Antihypertensives5 |
Increases hypotensive effects |
|
Estrogen7,12 |
Interact |
|
Hormone treatments14 |
Interact |
|
Tamoxifen4 |
Augments antiproliferative action (in vitro) |
Remedies: Candida, Skin
problems
|
Black Walnut (Juglans nigra) - Bark, leaf hull |
Atropine23 |
Interact |
|
Codeine23 |
Decreased absorption |
Remedies: Muscle spasms, Menstrual disorders,
Nervous & memory disorders
|
Blue Cohosh (Caulophyllum thalictroides) - Root |
Angina therapy4,5,9 |
Interact |
|
Antihypertensives5 |
Decreases effect of drug, increases blood pressure |
|
Nicotine5 |
Increases effects of nicotine |
Remedies: Skin & nail
health
|
Borage (Borago officinalis) - Seed Oil |
Epileptogenic drugs20 |
May manifest seizures (theoretical) |
|
Phenothiazines9 |
Interact |
Remedies: Diuretic, Emetic,
Purgative
|
Broom (Cytisus scoparius) - Aerial parts |
MAOIs23 |
Contains tyramine |
|
Beta blockers5 |
Potentiates drug |
|
Antihypertensives5 |
Interact |
Remedies: Hyperthyroidism, Mood, Overactive
heart
|
Bugleweed (Lycopus ssp) - Aerial parts |
Thyroid therapy23 |
Interact |
|
Beta blockers5 |
May mask symptoms |
Remedies: Liver disease, Hemorrhoids,
Digestion
|
Bupleurum (Bupleurum ssp) - Root |
Interferon23 |
May lead to serious lung disease |
Remedies: Acne, Psoriasis, Rheumatoid
arthritis
|
Burdock (Arctium lappa)
- Fruit & Roots
|
Oral hypoglycemics2,4,5,9 |
Increases hypoglycemia |
|
Insulin3,5 |
Hypoglycemic effect |
- Leaves |
Oral hypoglycemics4 |
Increases hypoglycemia |
Remedies: Acne, Psoriasis, Rheumatoid
arthritis
|
Calendula (Calendula officinalis) - Flowers |
Hexobarbitol2,3 |
Extends duration of drug action (rats) |
Remedies: Sedation, Colic
|
Catnip (Nepeta cataria) - Aerial parts |
Dextromethorphan23 |
Potentiates effect of drug |
Remedies: Stimulates immune system (taken by
HIV and cancer patients), Rheumatism, Gastric,
Ulcers, Tumors & Dysentery
|
Cat's Claw (Uncaria tomentosa) - Rootbark |
Anticoagulants5 |
Potentiates effect of drug |
|
Antihypertensives5 |
Potentiates effect of drug |
|
Oral contraceptives4 |
May antagonize effect of drug |
|
Hormone replacement therapy4,7 |
May antagonize effect of drug |
|
Immunosuppressives4 |
May antagonize effect of drug |
|
Insulins7 |
Interact |
|
Ulcer medications10 |
Interact |
|
Vaccines7 |
Interact |
Remedies: Digestion, Blood circulation,
Arthritis, Colds, Sore throat, Sinus problems
|
Cayenne Pepper (Capsicum frutescens) - Fruit |
All Drugs2 |
Increases hepatic metabolism |
|
Antihypertensives2,5,9 |
Interact |
|
ACE Inhibitors3,16 |
May increase cough |
|
Centrally acting adrenergic agents5
e.g. Clonidine, Methyldopa5 |
Decreases effect of drug |
|
Hexobarbital3 |
Increases plasma concentration and sleep with acute use and decreases with chronic use
(rats) |
|
MAOI2,5,9 |
Interact, hypertensive crisis |
|
Theophylline3,16 |
Increases absorption and bioavailability of drug |
Remedies: Digestion, Diuretic, Sleep aid,
Colitis, Diverticulosis, Fever, Headaches, Stress
|
Chamomile, German (Matricaria recutita) - flowers |
All Drugs5 |
Decreases absorption of drugs secondary to Chamomile
Antispasmodic activity in GI tract |
|
Anticoagulants5,9 |
Large doses of herb may interact |
Remedies: Diuretic,
Laxative
|
Chaparral (Larrea tridentata) - Aerial Parts |
Anticoagulants20 |
Chaparral has been shown to interact with platelet adhesion and aggregation in
aspirin-treated patients |
|
Barbiturates4 |
Inhibits metabolism |
|
MAOIs9 |
Excessive doses of Chaparral may interact with MAOI therapy |
Chasteberry (Vitex agnus-castus) - Berry |
Dopamine-receptor antagonists1,4,13
e.g. Antipsychotics & Metaclopramide14 |
Decreases therapeutic effect of drug (animal) |
|
Dopaminergic drugs |
Interact |
|
Hormone therapy4 |
Interact |
|
Oral contraceptives3,4 |
Interact with efficacy of drug |
Remedies: Joint health,
Arthritis
|
Chondroitin sulfate |
Anticoagulants5 |
Potentiates effects of drug |
Remedies: Diarrhea, Nausea, Blood
circulation, Fungal infection, Digestion
|
Cinnamon (Cinnamomum Zeylanicum) - Bark |
None reported1,5 |
|
Remedies: Antiseptic, Anti parasitic,
Digestive aid, Dental problems
|
Cloves (Syzgium aromaticum) - Buds |
Anticoagulants9 |
Potentiates anticoagulant effects of drug |
Remedies: Coughs, Respiratory ailments,
Diabetes
|
Coltsfoot (Tussilago farfara) - Leaf |
Antihypertensives4,5,9 |
Interact |
|
Cardiovascular therapy4,9 |
Interact |
Remedies: Wounds and many skin
problems
|
Comfrey (Symphytum officinale) - Leaf or Root |
None reported4,5 |
|
Remedies: Urinary tract
infections
|
Cranberry (Vaccinium macrocarpon) - Berry |
Renally excreted drugs5 |
May increase elimination of some drugs excreted in the urine. |
Remedies: Constipation, Indigestion, Water
retention, Alcoholism
|
Dandelion (Taraxacum officinale) - Root |
Antidiabetic agents5,9 |
May potentiate effect of drug, promoting hypoglycemia |
|
Antihypertensives5 |
Additive or synergistic hypotensive effect |
|
Lithium3,4 |
Toxic effect of lithium worsened |
- Leaf |
Diuretics2,4,5,9 |
Potentiates the diuretic action of drug (Herb is rich in potassium) |
Remedies: Indigestion, Heartburn and
Arthritis
|
Devil's Claw (Harpagophytum procumbens) - Root |
Cardiac therapy2,9 |
Interact |
|
Antiarrhythmic drugs2,4,5 |
Theoretical possibility of interaction due to herb's protective action against
arrhythmia |
|
Hypo/hypertensive therapy2,9 |
Interact |
|
Warfarin16 |
Increases risk of Purpura |
Remedies: Breast cysts, Menopause and PMS
symptoms
|
Dong Quai (Angelica sinensis) - Root |
Anticoagulants2,5,12 |
Interact |
|
ASA12 |
Interact |
|
Warfarin4,20 |
Herb may enhance the anticoagulant effect of drug |
|
HRT - Hormone Therapy22 |
Interact |
Remedies: Boost immune system to prevent
colds, flu, ear infections, sore throats, mouth ulcers (cankers), gingivitis and yeast
infections
|
Echinacea (Echinacea species) - Root/Leaf |
Cancer treatements4 |
Herb stimulated immune system |
|
Econazole nitrate cream3 |
Recurrence rate of vaginal candida infection decreases when the herb juice is used
simultaneously |
|
Immunosuppressive agents2,4,9
e.g. Corticosteroids & Cyclosporine4 |
Herb stimulates immune system |
|
Hepatotoxic drugs12 |
Increases liver toxicity with other hepatotoxic drugs |
|
Warfarin4 |
Increases bleeding time (anecdotal reports) |
Remedies: Colds, Herpes simplex, Sore throat,
Flu, Inflammation
|
Elder (Sambucus nigra) - Berry |
None reported1,2,5,10 |
|
Remedies: Arteriosclerosis, Diabetes, Eczema,
Fibrocyctic breast disease, PMS, Rheumatoid arthritis
|
Evening Primrose Oil (Oenothera biennis) - Seed |
Anticoagulants2,14,20 |
Interact, may reduce platelet aggregation and potentiate drug action |
|
Beta-blockers2,14 |
Decreases action of herb |
|
Corticosteroids2,14 |
Theoretically interact |
|
Epileptogenic drugs2,4,9
e.g. Phenothiazines2,5,9,14,19 |
Increases epileptic attacks |
|
Lithium carbonate2 |
Decreases neurotoxicity |
|
NSAIDs2,14 |
Theoretically interact |
|
Vasodilators20 |
May potentiate effect of drug |
Remedies: Lowering cholesterol and
triglyceride levels, Diabetes, Arteriosclerosis
|
Fenugreek (Trigonella foenumgraecum) - Seed |
All Drugs3,5,9,20 |
Absorption of all drugs may be affected due to mucilaginous fiber content and high
viscosity in gut |
|
Anticoagulants5,9,10 |
Interact |
|
Heart medications10 |
Interact |
|
Hormonal therapy9,10 |
Interact |
|
Hypoglycemic therapy5,9 |
Interact |
|
Insulin3,20 |
Dose may need adjustment due to hypoglycemic activity |
|
MAOIs9,10 |
Interact |
Feverfew (Tanacetum parthenium) - Leaf |
Anticoagulants2,4,12,13
e.g. Warfarin2,4 |
Potentiates effect of drug |
|
Aspirin12,13 |
Increases antithrombotic effect |
|
Corticosteroids2 |
Decreases effect of herb |
|
Imitrex12 |
Decreases efficacy of drug |
|
NSAIDs2,12 |
Decreases effect of herb |
|
Tylenol12 |
Decreases efficacy of drug |
Remedies: Bone, Nail, Teeth, Skin
health
|
Flax (Linum usitatissimum) - Seed |
All Drugs1,3,4,5,13,20 |
Absorption of drug delayed when herb used as a bulk laxative |
|
Insulin21 |
Potentiates effect of drug due to delayed absorption of glucose |
|
Laxatives5 |
Increase in laxative actions of flax |
|
NSAIDs4
e.g. Indomethacin4 |
Increases prevalence of stomach/intestinal ulcers |
Remedies: Allergies, Asthma, Eczema,
Irritable bowel syndrome, Menstrual cramps,
High blood pressure, Glaucoma
|
Forskohlii (Coleus forskohlii) - Root |
Clonidine23 |
Potential interaction |
Remedies: Cardiovascular system, Congestive
heart failure, Lowering cholesterol and triglyceride levels |
Garlic (Allium sativum) - Bulb |
Anticoagulants2,4,5,7,9,19
e.g. Warfarin1,3,11,12,16,19,20 |
Interact |
|
Antiplatelet therapy5 |
Anticoagulant activity of drug enhances (may double clotting time) |
|
ASA2,9,12 |
Enhances effects of antiplatelet therapy
Potentiates the anti-thrombotic effect of ASA |
|
Diabetic Therapy2,9
e.g. Insulin3 |
Dose of drug may need adjusting due to hypoglycemic effects of herb |
Remedies: Anti-nausea, Anti-vomiting, Blood
circulation, Indigestion
|
Ginger (Zingiber officinate) - Root |
All drugs3 |
Increases absorption of drug |
|
Anticoagulants2,4,5,9,11,19,20 |
Inhibitory effect on thromboxane synthesis |
|
Cardiac therapy2,9
|
Interact |
|
Cyclophosphamide3 |
Side effect of vomiting prevented by prior administration of acetone extract of ginger
or its component 6-gingerol (PO in Suncus/shrew) |
|
Diabetic therapy2,9
|
Interact |
|
Sulfaguanidine3,4 |
Increases absorption of drug (rats) |
Remedies: Alzheimer's disease, Blood
circulatory diseases, Depression, Diabetes, Male impotence, Migraine, Multiple sclerosis,
Tinnitus
|
Ginko (Ginko biloba) - Leaf |
Anticoagulants1,2,4,5,12,13,14,19
& Antiplatelet therapy20 |
Potentiates effect of drug - Monitor coagulation |
|
e.g. Aspirin3,12,16,20
NSAIDs4 Warfarin16,20
Ticlopidine20 |
May introduce spontaneous bleeding
Interact
Potentiates effect of drug |
|
MAOIs3,20
|
May potentiate effects of drug |
|
Papaverine3 |
Potentiates effect of intracavernosal injection for impotence (in 20% of patients for
whom previously ineffective) |
|
SSRIs20
|
Gingko may counter the sexual dysfunction that may be experienced with SSRIs |
|
Thiazide diuretic18 |
Herb decreases effect of drug, the interaction causes hypertension |
Remedies: Flu, Common cold, Sore throat,
Chronic fatigue syndrome, Fibromyalgia,
Alzheimer's disease, Arteriosclerosis, Chemotherapy support,
Male reproductive health, Stress, Diabetes
|
Ginseng North American (Panax quinquefolius) - Root |
Anticoagulation therapy3,4,12,16
e.g. Warfarin20 |
Interact
Decreases INR levels |
|
Antihypertensives4
e.g. Diuretics20 |
Interact
Decreases diuretic action |
|
Digitalis12
|
Increases toxicity |
|
Estrogen Therapy4,9 |
Interact |
|
Oral Hypoglycemia therapy4,5
|
Interact |
|
Insulin3 |
Dose adjustment due to hypoglycemic effect |
|
MAOIs1,3.4.5.9.11.12.20 |
Interact |
|
Oral contraceptives12 |
Interact |
|
Psychotherapeutic medication4,12/Antipsychotics19
e.g. Phenelzine4,9,16,20 |
Interact |
|
Steroids12,19 |
Interact |
Remedies: Alzheimer's disease, Attention
deficit disorder, Adjunctive chemotherapy,
Chronic fatigue syndrome, Common cold, Diabetes, Flu, Fibromyalgia, Stress
|
Ginseng Siberian (Eleuthero coccus senticosus) - Root |
Anticoagulants2,4 |
Interact |
|
Antipsychotics4,9 |
Interact (Stimulant activity) |
|
Barbiturates2,4
e.g. Hexobarbital3,5 |
Potentiates effects of drug
Increases effect of drug due to inhibition of its metabolic breakdown |
|
Cardiac therapy2,9 |
Interact |
|
Diabetes therapy2,4,9 |
Interact |
|
Digioxin2,5,16,19 |
Increases serum digoxin levels |
|
Estrogen4 |
Potentiates effect of drug |
|
Hypertension therapy2,4 |
Contra-indicated |
|
Hypotension therapy2,9 |
Interact |
|
Insulin3 |
May need to adjust dose due to hypoglycemic effect |
|
Monomycin & Kanamycin3 |
Increases efficacy in treating Shigella dysentry and Proteus enterocolitis probably
due to enhancement of t-lymphocyte activity |
Remedies: Arthritis, Joint
pain
|
Glucosamine Sulfate (2-Amino-2-deoxyglucose) |
Diabetic medication15 |
Causes a decrease in insulin secretion and in insulin sensitivity (in animal
studies) |
Remedies: Common cold, Chronic ear
infections, Urinary tract infections, Crohn's disease
|
Goldenseal (Hydrastis canadensis) - Root |
Anticoagulants4,5,9 |
Potential interaction |
|
Antihypertensives5
e.g. Beta blockers5
Calcium channel blockers5 |
Increases effect of drug |
|
Barbiturates2,4
e.g. Barbitu |
Increases sleeping times (rats) |
|
Cardiovascular medications4
e.g. Digoxin5 |
Interact
Increases effect of drug |
|
CNS depressants5
e.g. Alcohol, benzodiazepines5 |
Enhances sedative effects |
|
Oral Hypoglycemia Therapy22 |
Herb lowers blood sugar levels |
Remedies: Appetite stimulant, Digestion,
Diuretic
|
Grapefruit (Citrus paradisi) - Fruit/Juice |
All Drugs including:
Benzodiazepines3,18
e.g. Midazolam, triazolam, alprazolam18, Buspirone18 |
Increases bioavailability
Inhibits metabolism by cytochrome P450-3A enzymes |
|
Calcium Antagonists3,18
e.g. Amiodipine, verapamil, nisoldipine, nifedipine, nitrenipine, felodipine, nimodipine,
nicardipine |
|
|
Cavedilol18 |
|
|
Cisapride18 |
|
|
Clomipramine18 |
|
|
Coumarin3 |
|
|
Cyclosporin3,18 |
|
|
Ethinyl estradiol3,18 |
|
|
HMG CoA reductase inhibitors18
e.g. Atorvastatin, cerivastatin, lovastatin, simvastatin18 |
|
|
Saquinavir18 |
|
|
Tacrolimus18 |
|
|
Terfenadine3 |
|
Remedies: Good nutritional
value
|
Grape Seed Extract |
None reported5 |
|
Remedies: Stimulates immune system,
Infections, Gum disease, some cancer risk reduction,
Lowers cholesterol level, High blood pressure, High triglyceride levels |
Green Tea (Camellia sinensis) - Leaf |
All Drugs |
Green Tea has similar interactions as occur with caffeine |
|
Calcium12 |
Decreases absorption of calcium |
|
Doxorubicin5 |
May enhance the antitumor activity of doxorubicin |
Remedies: Angina, Arteriosclerosis, High
blood pressure
|
Hawthorn (Crataegus laevigata) - Aerial parts |
Antihypertensives5 |
Increases hypotension |
|
Cardiac glycosides3,5,12,19
e.g. Digitoxin, Digoxin3, Digitalis1,3,4 |
Potentiates effect of drug (helps lower digoxin levels where toxicity is a
concern) |
|
Cardiac medications7,9
e.g. Nitrates5 |
Interact
Increases hypotension |
|
CNS depressants5 |
Addictive effects |
Remedies: Anxiety,
Insomnia
|
Hops (Humulus lupulus) - Strobiles |
Alcohol2,9,14,20 |
Potentiates action of alcohol |
|
CNS depressants5 |
Increases effect of drug |
|
Cytochrome P450 metabolized drugs2,5 |
Yet to be evaluated |
|
Pentobarbital3 |
Increases sleeping time (mice) |
|
Phenothiazine-type antipsychotics5 |
Combination of herb and drug increases hyperthermia |
|
Sedative-hypnotics2,9,14,20 |
Potentiates effect of drug |
Remedies: Varicose veins, Hemorrhoids, Blood
circulation
|
Horse Chestnut (Aesculus hippocastanum) - Seed |
Anticoagulants3,5
ASA3,5 |
Increased risk of bleeding |
Remedies: Coughs, Diuretic, Sinus, Throat and
lung problems
|
Horseradish (Armoracia rusticana) - Root |
Thyroid medications9 |
Interact |
Remedies: Urinary tract infections, water
retention
|
Juniper (Juniperus communis) - Berry |
Diuretic therapy2,9 |
Potentiates effect of drug |
|
Hypoglycemic therapy2,9 |
Potentiates effect of drug |
Kava (Piper methysticum) - Root |
Alcohol1,2,3,5,7,12,14 |
Potentiates action of herb |
|
Anticoagulants19 |
Interact |
|
Antidepressants7,12 |
Interact |
|
Antipsychotics7 |
Interact |
|
Barbiturates1,2,4,5,7
e.g. Hexobarbital2
e.g. Pentobarbital3,5 |
Potentiates action of barbiturates
Potentiates effect of drug (animals)
Potentiates effect of drug |
|
Benzodiazepines2,3,4,12,14,19/Tranquillizers12
e.g. Alprazolam2,5,20 |
Potential interaction
Potentiates effect of drug |
|
Centrally acting drugs1,2,4,7,20 |
Potentiates effect of drug |
|
CNS depressants3,5 |
Potentiates effect of drug |
|
Levadopa3 |
Decreases efficacy |
|
Hepato toxic drugs |
Potentiates effect of drug |
Remedies: Herpes simplex, Indigestion,
Insomnia, Nerve pain, Hyperthyroidism
|
Lemon Balm (Melissa officinalis) - Leaf |
CNS depressants14 |
Interact |
|
Hexobarbital3 |
Enhances effect of drug |
|
Pentobarbital2,3,4 |
Promotes hypnotic action (mice) |
|
Thyroid medications2,4,14 |
Interact |
Remedies:
Asthma, Bronchitis, Canker sores, Eczema, Herpes simplex, Indigestion, Heartburn,
Peptic ulcer, Chronic fatigue syndrome
|
Licorice (Glycyrrhiza glabra) - Root |
Agents that prolong the QT interval5
e.g. procainamide, quinidine, terfenadine5
|
May prolong the QT interval |
|
Antihypertensives4,5,12 |
Interact |
|
Aspirin3,20 |
Deglycyrrhizinated licorice decreases ulcer formation (rats) & gave greater
protection from ASA-induced gastric mucosal damage when used with cimetidine (rats) |
|
Cardiac glycosides2,3,11
e.g. Digitalis1,3,12,20
Digoxin5 |
Affect potassium levels
Iincreases toxicity due to decreases in potassium |
|
Cardiovascular drugs4 |
Interact |
|
Cathartics4
e.g. Stimulant laxatives3 |
Interact
Additive effect - increases potassium loss |
|
Corticosteroids3,4,5,11,20
e.g. Hydrocortisone2,3,16,
Prednisolone2,16 |
Interact
Potentiates effect of drug
Inhibit metabolism, increases plasma concentration |
|
Diuretics3,4,5,11,12,20 e.g. Loop diuretics2,11,
Potassium-sparing diuretics2,
Potassium-excreting agents or amiloride4, Spironolactone3,4,5,11,
Thiazide1,3,11 |
Affects potassium, potentiates potassium depletion |
|
Hormonal therapy4,9
e.g. Oral contraceptives16 |
Interact
Hypertension, edema, hypokalemia |
|
Estrogen & antiestrogen2 |
Interact |
|
Insulin2,3,4,9 |
Increases electrolyte disturbances |
|
Nitrofurantoin2 |
Increases bioavailability |
Remedies: Coughs, Colds, Asthma, Bronchitis,
Flu, cardiovascular, Epilepsy
|
Lobelia (Lobelia inflata) - Aerial parts |
Nicotine therapy5 (smoking cessation treatments) |
Contra-indicated - Nicotine and Lobelin are chemically similar in structure |
Remedies: Breathing problems, Asthma, Nasal
congestion
|
Ma Huang (Ephedra sinica) - Aerial parts |
All Drugs2 |
Herb has similar interactions to those occurring with Ephedrine |
|
Anesthetics4 |
Interact |
|
Agents that influence urine pH
e.g. Antacids3,4
Acetazolamide20 |
Interact
Acetazolamide may cause increased concentration of ephedrine due to alkalinization of the urine |
|
ASA4 |
Potentiates effect of drug |
|
B adrenegic blockers4,5 |
Interact |
|
Cardiac glycosides1,4,11,13
e.g. Digitoxin7 |
Disturb heart rhythm
Interact |
|
Corticosteroids2
e.g. Dexamethasone3 |
Interact
Increases clearance and thereby reduces effect |
|
Centrally acting medications2,4
e.g. Antidepressants2
Antihypertensives2,4
Clonidine20 |
Interact
Interact
Interact
Clonidine may augment the pressor response to ephedrine |
|
Ephedra alkaloids5 |
Hypertensive crisis |
|
Ergot alkaloid derivatives11 |
Interact |
|
Guanethidine1,2,4,7,11,13,20 |
Increases sympathomimetic effect |
|
Halothane1,2,11,13,20 |
Disturbs heart rhythm |
|
MAOIs1,2,3,4,7,11,13
e.g. Tranylcypromine, selegiline, phenelzine, moclobamide3, isocarboxazid20 |
Increases sympathomimetic effect
Severe hypertension |
|
Methyl Xanthines3
e.g. Theophylline2,3,4,5,20 |
Interact, increases side effect (GI and CNS) of both herb and drug |
|
Oxytocin1,2,4,11,13 |
Hypertension |
|
Phenothiazine5 |
Hypotension |
|
Reserpine3,20 |
Indirect sympathomimetic effects of ephedrine are antagonized |
|
Secale alkaloid derivatives1,2 |
Hypertension |
|
Sodium Bicarbonate20 |
Ephedrine toxicity increases due to decreased elimination |
|
Stimulants2 |
Interact |
|
Sympathomimetic agents4,20 |
Interact |
Remedies: Peptic ulcer, Chron's disease,
Diarrhea, Asthma, Common cold, Sore throat
|
Marshmallow (Althaea officinalis) - Root |
All Drugs1,3,4,5,10 |
Delays absorption of drug |
|
Dexamethasone4 |
Potentiates effect of drug |
|
Hypoglycemic therapy9,10 |
Interact |
|
Insulin5 |
Increases hypoglycemic effects |
|
Sulfonylureas5 |
Increases hypoglycemic effects |
Remedies: Diarrhea, Stomach
problems
|
Meadowsweet (Filipendula ulmaria) - Leaf/Flower |
All Drugs2,9
e.g. Anticoagulants2 |
Herb has similar interactions to those occurring with salicylates
Interact |
Remedies: Gallstones, Psoriasis, Liver
health
|
Milk Thistle (Silybum marianum) - Seed |
All Drugs2 |
Increases live metabolism of all drugs |
|
Acetaminophen4,19 |
Reduces hepatotoxicity |
|
ASA3,4 |
Altered metabolism in people with liver cirrhosis might be improved |
|
Butyrophenones20 |
Reduces lipid peroxidation |
|
Carbon tetrachloride4,19 |
Reduces hepatotoxicity |
|
Cisplatin3,4 |
Reduces hepatotoxicity |
|
Cyclosporine4 |
Reduces hepatotoxicity
Synergistic antiproliferative effect on human ovarian and breast cancer cell lines |
|
Doxorubicin4 |
Synergistic antiproliferative effect on human ovarian/breast cancer cell lines |
|
Ethanol4,19 |
Reduces hepatotoxicity |
|
Iron4 |
Reduces hepatotoxicity |
|
Phenothiazines4,20 |
Reduces hepatotoxicity |
|
Phenytoin21 |
Reduces hepatotoxicity |
Remedies: Blood pressure and heart, Mood,
Migraine
|
Mistletoe (Viscum album) - Aerial parts |
Anticoagulant therapies9 |
Interact |
|
Antihypertensives4,5,10 |
Increases hypotensive effects/check blood pressure regularly |
|
Antidepressants9,10 |
Interact |
|
Cardiac drug5,9,10 |
Increases cardiac depression |
|
Coagulant therapies9 |
Interact |
|
CNS depressants5 |
Increases sedative effects |
|
Hypotensive therapies9 |
Interact |
|
Immunosuppressants5,9 |
Cytotoxic and immunostimulant effects |
|
MAOIs4 |
Interact/monitor |
Remedies: BPH (enlarged prostate), hay
fever
|
Nettle (Urtica dioica) - Leaf |
Anticoagulants4/
Coagulant therapy4 |
Interact |
|
Antihypertensives2,4,9 |
Interact |
|
CNS depressants4,9 |
Potentiates effect of drug |
|
Diabetic medication2,4,9 |
Interact |
|
Diclofenac (low dose)3,4 |
Leaf extract enhances anti-inflammatory effect of diclofenac
Potentiates effect of drug |
|
Diuretics2,5 |
Potentiates effect of drug |
|
Hypotension medication4,9 |
Interact |
- Root |
Protatic Hyperplasia Therapy22
e.g. Tamsulosin |
Potentiates effect of drug |
Remedies: Anxiety,
Insomnia
|
Passionflower (Passiflora incarnata) - Leaf |
Barbiturates4
e.g. Hexabarbital, Pentabarbital2,3 |
Increases hypnotic action
Increases sleeping time (animal) |
|
Centrally Acting Medications2,4,5 |
Increases hypnotic action and potential for monoamine oxidase inhibition |
|
CNS depressants20 |
Potential for additive effects and increases sedation |
|
MAOI Antidepressants5,7,9 |
Interact |
Remedies: Infections and yeast
infections
|
Pau D'arco (Tabebuia impetiginosa) - Bark |
Anticoagulants5,20 |
May potentiate effects of drug, prolongation of prothrombin time20 |
|
Iron5 |
Decreases absorption of iron |
Remedies: Migraine, Nerves, Stomach disorder,
Heartburn, Herpes, Abdominal cramps
|
Peppermint (Mentha x piperita) - Leaf |
Ulcer treatment e.g. H2
Receptor Blockers |
May antagonize achlohydria |
Remedies: Chronic venous
insufficiency
|
Pine Bark Extract (Pinus maritima) |
None reported4,5 |
|
Remedies: Anemia, Skin healing, Respiratory
problems, Immune system support, Digestion
|
Propolis
- Resin |
Tetracycline24 |
Increases effectiveness |
Remedies: Constipation, Diarrhea,
Hemorrhoids, Irritable bowel syndrome, Obesity, Arteriosclerosis, High cholesterol, High
triglyceride level, Psoriasis
|
Psyllium (Plantago psyllium)
- Seed |
All drugs1,3 |
May delay absorption of drugs |
|
Anti-coagulants21 |
Delays absorption of drug |
|
Anti-convulsants
e.g. Carbamazepine5,20 |
Decreases absorption and concentration of drug |
|
Cardioactive drug5
e.g. Beta blockers, calcium channel blockers, digitalis5 |
A possibility that the herb enhances digitalis effect of the drug (highly
speculative) |
|
Insulin3 |
Drug dosage must be adjusted due to slowing of dietary carbohydrate absorption |
|
Lithium3,5,16 |
Decreases concentration due to reduction of drug absorption |
Remedies: Vitiligo (whitening of skin),
Impotence, Female infertility, Urinary problems
|
Puncture Vine (Tribulus terrestris) |
None reported4 |
|
Remedies: Urinary problems, Enlarged
prostate
|
Pygeum (Prunus africana) - Bark |
Antibiotics for prostate and bladder infections4 |
Enhances effectiveness of drug |
Remedies: Coughs, Eczema, Possible cancer
reduction
|
Red Clover (Trifolium pratense) - Blossoms |
Anticoagulants5,9,10
e.g. Heparin, Warfarin5 |
May increase risk of bleeding |
|
Antiplatelet agents5
e.g. ASA, clopidogrel, ticlopidine5 |
May increase risk of bleeding |
|
Hormone Replacement Therapy9,10 |
Interact |
|
Oral Contraceptive5,9,10 |
May enhance action of drug by increasing estrogen components |
Remedies: Menstrual problems, Diarrhea,
Canker sores
|
Red Raspberry (Rubus idaeus) - Leaf |
Antidiabetic agents5,9 |
Increases effectiveness of hypoglycemic action |
Remedies: Lowering cholesterol
levels
|
Red Yeast Rice |
lovastatin23
Simvastatin23
Atorvastatin23 |
Additive effect similar in (Cholestin) |
Remedies: Colds,
Infection
|
Rosehips (Rosa canina) |
None reported5 |
|
Remedies: Circulatory system, Heart problems,
High blood pressure, Menstruation
|
Rosemary (Rosmarius officinalis) - Leaf |
Disulfiram5 |
Disulfiram reaction if herbal product contains alcohol |
Remedies: Appetite stimulant, Chronic fatigue
syndrome, Liver disease, Insomnia, Multiple sclerosis
|
Royal Jelly |
Antidiabetic agents5 |
May lead to loss of glycemic control in diabetic patients |
Remedies: Menopause, Tonsillitis,
Fever
|
Sage (Salvia officinalis) - Leaf |
Anticonvulsants5,9 |
Lowers seizure threshold |
|
Antidiabetic agents5,9
e.g. Insulin5 |
Antagonizes glycemic control |
|
Sedatives9 |
Herb may potentiate sedative effects of other drugs |
Remedies: BPH (enlarged
prostate)
|
Saw Palmetto (Serenoa repens) - Berry |
Hormone replacement therapy2,4,9 |
Interacts because of its anti-androgen and estrogenic activity |
|
Oral contraceptives2,4,9 |
Interacts because of its anti-androgen and estrogenic activity |
Remedies: Coughs, Asthma, Urinary problems,
Tonic
|
Schisandra (S. chinensis) - Berry |
Acetaminophen23 |
Reduces hepatotoxicity |
Remedies: Infertility, Nerve
disorders
|
Scullcap (Scutellaria laterifolia) - Aerial parts |
Centrally-acting medications2 |
Potentiates effect of drug |
|
Sedatives and tranquillizers3,4 |
Interact |
Scullcap, Chinese (Scutellaria baicalensis) - Root |
Immunosuppressives5 |
Possible interaction |
|
Platelet aggregation inhibitors3,4 |
Potentiates effect of drug |
Senna (Cassia ssp) - Leaf, Pod |
Indomethacin5 |
Decreases drug levels |
|
Calcium channel blockers5 |
Potentiates potassium depletion |
|
Digoxin23 |
Interacts |
Remedies: Sore throat, Fevers, Heart
problems
|
Slippery Elm (Ulmus rubra) - Aerial parts |
All Drugs7 |
May interfere with the absorption of drugs taken simultaneously |
Remedies: Depression, Vitiligo (whitening of
skin), Recurrent ear infections
|
St. John's Wort (Hypericum perforatum) - Aerial parts |
All Drugs21,22 |
Drugs metabolized by cytochrome P450 3A4 enzyme system have potential to interact |
|
Antabase12 |
Interact |
|
Anitdepressants4,5,12,17
e.g. Trazadone
nefazodone16,17
see MAOIs & SSRIs below |
Serotonin syndrome |
|
Anti-epilepsy drugs17
e.g. Phenytoin
carbamazepine
phenobarbital17 |
Interact |
|
Anti-retroviral drugs
e.g. Indinavir |
Interact |
|
Atypical antipsychotics12
e.g. Olanzapine, risperidone12 |
Interact |
|
Beta2 agonists12 |
Interact |
|
Dextromethorphan2,12 |
Interact |
|
Dibenzazepine Derivatives2
e.g. Amitriptyline, doxepin, carbamazepine2 |
Interact |
|
Digoxin5,16,17 |
Interact |
|
Dopamine agonists12 |
Interact |
|
Immunosuppressants17
e.g. Cyclosporine16,17,20 |
Interact - Decreases cyclosporine plasma concentration20 |
|
Meperidine2 |
Interact |
|
Metronidazole12
Midodrine20 |
Interact
Enhances pressor effect |
|
Migraine therapies17 |
Interact |
|
Monoamine Oxidase Inhibitors (MAOIs)2,3,5,9,12,20
e.g. Phenelzine, tranylcypromine, isocarboxazid |
Interact |
|
Narcotics5
e.g. Morphine2 |
Interact |
|
Oral Contraceptives16,17 |
Interact - can make ineffective |
|
Reserpine3 |
Decreases effect of drug (mice) |
|
Selective Serotinin Reuptake Inhibitors (SSRIs)2,3,4,5,7,12,16,17,20
e.g. Fluoxetine, paroxetine5, sertraline |
Serotonin syndrome |
|
Sympathomimetics2,5,12
e.g. Ephedrine, methyldopa, dopamine, trytophan |
Interact |
|
Theophylline4,12,16,17,20 |
Interact |
|
Tyramine containing foods2,5 |
Decreases theophylline level
Interact (speculative) |
|
Warfarin17 |
Interact |
Remedies: Yeast infection, Vaginitis,
Athletes foot, Acne
|
Tea Tree Oil (Melaleuca alternifolia) - Leaf |
None reported2,4,5,12 |
|
Remedies: Digestion, Fever, Headache, High
cholesterol, Skin problems
|
Thyme (Thymus vulgaris) - Leaf & Flower |
None reported1,2,5 |
|
Remedies: Respiratory problems, Mood,
Tonic
|
Turkey Tail (Coriolus versicolor) |
Cyclophosamide23 |
Cyclophosamide23 |
Remedies: Bursitis, Rheumatoid arthritis,
Liver health, Arteriosclerosis
|
Tumeric (Curcuma longa) - Root |
Anticoagulants5 |
Additive effects on platelets |
|
Immunosuppressants5 |
Decreases effects of drug |
|
NSAIDs5 |
Inhibits platelet function and increases risk of bleeding |
|
Reserpine and indomethacin3 |
Tumeric root solid alcoholic extract reduces the frequency of gastric and duodenal
ulcer (rats) |
Remedies: Urinary tract
infection
|
Valerian (Valeriana officinalis) - Root |
Alcohol5,11,16 |
Potentiates effects of alcohol |
|
Anticonvulsants12 |
Increases seizures |
|
Barbiturates19
e.g. Pentobarbital, thiobarbital3 |
Increases sleeping time |
|
Benzodiazepines3,19
e.g. Diazepam3 |
May be helpful in withdrawal from benzodiazepines |
|
CNS depressants2,5,14,19 |
Potentiates effects of drug |
|
Sedative medications4,9,11,12,14 |
Potentiates effects of drug |
Remedies: High cholesterol, High triglyceride
levels, Abdominal cramps, Menopause,
Muscle pain and spasms
|
Wild Yam (Dioscorea vilosa) - Root |
Oral Contraceptive22 |
Interact - may interfere with effectiveness of contraceptive |
Remedies: Headache, Pain, Backache, Nerve
pain, Toothache
|
Willow (Salix) - Bark |
All Drugs1,2,9 |
Willow has similar interaction to those occurring with salicylates. Irreversible
inhibition of platelet aggregation by aspirin cannot be induced by structurally different
salicin21 |
|
Anticoagulants5,9 |
Increases bleeding |
|
Antihypertensives5 |
Reduces effect |
|
Diuretics5 |
Increases risk of salicylate toxicity (highly speculative) |
|
Methotrexate9 |
Interact |
|
Metoclopramide9 |
Interact |
|
NSAIDs5,13 |
Interact |
|
Phenytoin9 |
Interact |
|
Probenecid9 |
Interact |
|
Salicylates9,13 |
Interact (no cases reported) |
|
Spironolactone9 |
Interact |
|
Valproate9 |
Interact |
Remedies: Inflammation, Improves blood
clotting, Diuretic, Fever, Some inflammatory disorders
|
Yarrow (Achillea millefolium) - Aerial parts |
Antacids4 |
Interact |
|
Anticoagulant therapy4,5,9 |
Interact |
|
CNS depressants5 |
Increases sedation |
|
Diuretics4 |
Interact |
|
H2receptor antagonists4 |
Interact |
|
Hypertensive4,5,9 / Hypotensive therapy4,9 |
Interact |
|
Sedatives4 |
Interact |
Remedies: Depression, Male
impotence
|
Yohimbe (Pausinystalia yohimbe) - Bark |
a-adrenoceptor blocking agents3
e.g. Phenoxybenazamine, phentolamine3 |
Increases toxicity of yohimbine |
|
Amobarbital3 |
Interact |
|
Antidepressants5,7,20 |
Interact |
|
Atropine3 |
Interact |
|
Beta blockers3
e.g. Propranolol, penbutolol, metrprolol3 |
Protects against yohimbine toxicity (mice) |
|
Central a2-adrenergic agonists3
e.g. Guanabenz, a-methylnorepinephrine3 |
Reverses hypotensive effects |
|
Clonidine3 |
Reverses hypotensive effects |
|
Hypotensive drugs1,20 |
Potentiates |
|
MAOIs1,3,20 |
Potentiates |
|
Naloxone3,20 |
Affects synergistically enhances |
|
Phenothiazines3
e.g. Chlorpromazine, promazine3 |
Increases toxicity of yohimbine |
|
Reserpine3 |
Interact |
|
Sedatives3 |
Increases effect of drug |
|
SSRIs5 |
Increases stimulation |
|
Sympathomimetics3,5,10
e.g. Epinephrine, ephedrine, amphetamine, cocaine3 |
Increases toxicity of yohimbine |
|
Thiozanthenes3
e.g. Chlorprotixene3 |
Increases toxicity of yohimbine |
|
Tricyclic anti-depressants3,5,16
e.g. Clomipramine3,20, imipramine, amitriptyline3 |
Combination of herb and drug may cause hypertension
Lower doses of yohimbine may have favorable effect in orthostatic hypotension induced by tricyclic
anti-depressants |
|
Tyramine containing foods5,20 |
Increases blood pressure |
References
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