People use herbal supplements and vitamins as supplements for health and wellbeing. Herbal supplements can be a healthful addition to some diets. A side effect of herbs and supplements is as common as in prescribed medicine. Most of the products are considered natural and automatically seen to be more healthful than prescription medication even though some prescription medication also may have botanical origins.

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Nutritional Supplements

Anything added to a person’s diet to improve health is considered a supplement. Most vitamins, minerals, antioxidants, and other substances needed for a healthy body can be found in in food. The medical profession considers most herbal supplements fairly safe when taken as directed in moderate amounts. Some herbal supplements, such as ginger and garlic are used as food additives and are used in cooking. Dietary supplement side effects are something the consumer should know about.

The Federal Drug Administration And Herbal Supplements

The Federal Drug Administration (FDA) classifies herbal supplements in a group known as  food supplements. Because these are used to “supplement the diet,” the FDA doesn’t test them to verify their validity, claims and content. The maker is required to send the FDA a letter that it doesn’t expect the product to produce any negative side effects. Congress allowed this classification partly because of pressure from the supplement lobby. Therefore, dietary supplements don’t have to meet the requirements medicine for advertisements, marketing and manufacture.  

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It’s not uncommon to see reports of tests on herbal supplements checked by a lab where the contents widely differ from the amounts and content listed on the label. The content of each batch may vary widely. The FDA investigates herbal supplements only when health hazards become known.

Common Herbs: Uses And Side Effects

Black cohosh (Actaea racemosa and Cimicifuga racemosa)is used for menopausal symptoms. It is native to North American and is also known as black snakeroot, bugbane, bugwort, rattleroot, rattletop, rattleweed, macrotys and others. In addition to menopausal and hot flash uses it is used for malaise, malaria, rheumatism, fever, kidney problems, headaches, sleep disorders, heart palpitations, night sweats and as a diuretic.   

Side effects include gastric complaints and headaches. It isn’t recommended for children under 18, pregnant women, people with liver disease, women taking birth control pills, hormone replacement therapy, blood pressure medicine or sedatives. Notify physician if taking black cohosh.   

Echinacea (Echinacea angustifolia) is an immunity booster and used to heal wounds, boost the immune system, shorten colds and reduce their severity.

Side effects include intestinal problems such as nausea, abdominal pain, diarrhea, and vomiting. It’s possible to have allergic reactions if the user is allergic to sunflower and daisy-aster plants.

Evening primrose oil (Oenothera biennis) is used for stomach cramps, breast pain and other menopause symptoms. It’s also used for eczema, ADHD, rheumatoid arthritis, and osteoporosis.

Evening primrose oil may increase the risk for pregnancy complications. It is a coagulant; don’t take with blood thinner drugs and aspirin or Ibuprofen. Evening primrose oil will counteract any blood thinner medication being taken.

Feverfew (Tanacetum parthenium) uses include relieving headaches, migraines, arthritis.

Side effects are intestinal discomfort if taken orally. Chewing leaves may inflame tissue and mouth ulcers.

Garlic (Allium sativum) is a widely used condiment and food additive reported to have many benefits in cardiovascular health.

If applied to the skin garlic may cause burns, blistering and irritation. Orally may cause heartburn, diarrhea and nausea. Garlic is a blood thinner and interacts with other blood thinner prescriptions.

Ginger (Zingiber officinale)is a common spice and digestive aid used in beverages, cooking and baking. Ginger’s health benefits include reducing nausea, motion and morning sickness.

Ginger side effects may be abdominal discomfort, heartburn, and diarrhea if used in high doses. It’s an anti-coagulant and shouldn’t be used with prescription drugs or other herbs that cause bleeding.

Ginkgo biloba (Ginkgo biloba) is used for memory improvement and dementia, PMS, and glaucoma.

Ginko biloba can cause headache, dizziness, constipation, stomach upset, allergic skin reaction and bleeding. Check with physician when using blood thinners as it is also an anti-coagulant.

Ginseng (Panax ginseng) is touted as a mood improvement supplement. Other uses include increasing athletic abilities and cognitive functions.

It increases breast tenderness, can make menstrual flow abnormal, and cause insomnia. Ginseng may clot blood and work in opposition to anticoagulants and blood thinners. Ginseng is not recommended for patients with diabetes, autoimmune problems, or bleeding conditions. Don’t take with caffeine or other stimulants.

Hawthorn (Crataegus) is used to treat heart disease. It is used to relieve angina (chest pains), high blood pressure, hardening of the arteries, irregular heartbeat and heart failure. In controlled studies, hawthorn has been found to be somewhat helpful with mild coronary cases. It is also used for digestive ailments, anxiety, sedative, increase urine output and menstrual problems.

Hawthorn may increase the effects of other medications used to lower blood pressure, make heartbeat regular, angina, and nitrates such as nitroglycerin. Consult with a doctor before hawthorn use. Heart disease is a serious matter, and hawthorn may interfere with prescribed treatment.

Kava kava (Piper methysticum) reportedly reduces insomnia, restless, tension and anxiety.

Kava kava is toxic to the liver. It’s not recommended for people with Parkinson’s, depression, or liver disease. Don’t use with alcohol, barbiturates, or benzodiazepines. Don’t drive after use. Kava may cause intestinal discomfort, dizziness, drowsiness, allergic skin reactions, and dry mouth. May cause urine to darken, fatigue and jaundice (yellow skin).

 St. John's wort (Hypericum perforatum) is taken orally or applied directly on the skin. It may treat depression if taken orally, seasonal affective disorder, obsessive compulsive disorder, and premenstrual syndrome. It can be applied directly to the skin for inflammation, muscle aches and minor burns.

Side effects may include insomnia, intestinal discomfort, anxiety, diarrhea, irritability, dry mouth, fatigue, dizziness, and headache. Don’t use St. John’s wort with major depression, bipolar depression, Alzheimer’s and ADHD. It may increase sunburn effects. It may interfere with chemotherapy cancer treatments, hypertension medications and oral contraceptives.  Not recommended for use with alcohol, antidepressants, or barbiturates.

Saw palmetto (Serenoa repens) is used to improve prostrate health, increase sexual energy and increase breast size.

Side effects include headache, nausea, constipation, vomiting and diarrhea. Saw palmetto is an anticoagulant, and may induce bleeding.

Valerian (Valeriana officinalis) is used as a relaxant to induce sleep. The user is less drowsy in the morning after using it.

Valerian Root will interact with psychotic medications. Don’t used with these medications unless consulting a physician.

This list is partial and in no way all inclusive or complete. As a general rule physicians don’t recommend herbs for anyone with liver disease, or has an autoimmune problem. Inform your physician if using herbal or dietary supplements.

When used in small amounts as recommended herbal supplements are generally safe or next best, non-effective. Doctors recommend not using them for extended periods. The worst case is they can be hazardous to organs such as the liver, kidneys and blood if taken for too long or in too large amounts.

Patients should include the herbs they take along with other medications on the list for their doctor’s evaluation. Pregnant or lactating women should inform their physician of herbal supplements they normally take. Many herbal supplements are blood thinners so it is important to inform the doctor of which herbs a person takes if having surgery. Inform the physician of any herbal supplements infants or small children are taking. Herbal supplements should be treated the same as prescribed medicine.