Most people think that because herbs are natural, they must be safe. For long, many herbs have been touted as natural cures for various ailments or for their abilities to enhance general wellbeing. That is, however, not the case. Herbal products and supplements are not as stringently controlled, nor have they had a lot of research done on them, so the effects that they have on people who are on prescribed or over-the-counter drugs are not well known. Manufacturers are not obliged to warn customers of potential side effects or the dangers of toxicity due to non-uniform dosages.
The research on the interactions between common herbs and medications has been picking up in recent years, and doctors now have information on these herbs while treating and prescribing medications to their patients. It is imperative for patients to inform their physician of any supplements they may be taking. The following common herbs are some of the most popular supplements available today, but they all are dangerous when paired with certain medications.
Garlic
Most people don’t know that garlic is an herb. There is some scientific evidence that garlic and garlic supplements are beneficial in lowering high blood pressure, reducing the development of atherosclerosis, and reducing the risk of certain cancers. However, garlic has an adverse effect when taken with anticoagulant drugs like Warfarin, as there is an increased risk of bruising and bleeding. The effectiveness of medications that treat HIV/AIDS, like Viramune, Rescriptor, and Sustiva, are reduced because garlic speeds up the breakdown of the medicines in the body.
Chamomile
Chamomile is most commonly used for its mild sedative properties, helps in fighting inflammation of the sinuses and throat, and reduces flatulence and nausea. When taken with anticoagulant drugs like Warfarin, the effect of this drug is reduced. The effect of certain birth control pills is also reduced. Certain medications like Mevacor, Nizoral and Elavil, are changed and broken down by the liver. The side effects of these medications can be magnified when chamomile is also ingested.
St. John’s wort
St. John’s wort is commonly used to treat depression, anxiety, fatigue and insomnia because it increases a brain chemical called serotonin. Medications like Prozac and Zoloft are prescribed to treat depression, and when taken with St. John’s wort, the level of serotonin increases too much, causing shivering, anxiety and even heart problems. The anti-anxiety drug Xanax, is less effective in combination with the herb because the body breaks down the drug too fast. Another serious side effect of the herb happens when it is taken with Achromycin and Feldene, two drugs that increase sun sensitivity. In combination, they can cause serious sun burn, blisters and rashes.
Echinacea
Echinacea is an herb commonly found in the form of tablets, tea or juice, and is used to fight upper respiratory infections by decreasing inflammation and raising immunity. Echinacea causes liver toxicity and should not be taken with medications that affect the liver. These include Nizoral, Arava and Rheumatrex. Imuran, Simulect, Neoral and Sandimmune are drugs that depress the immune system and therefore should not be taken with this herb.
Ginkgo Biloba
This herb is the oldest known medicinal herb. Ginkgo improves blood circulation to all parts of the body, so it is used to arrest the deterioration of eyesight due to age-related macular degeneration and other eye problems. It also improves cognitive function, so it is used to slow down dementia. Ibuprofen, aspirin, Warfarin and other anti-coagulant drugs are dangerous in combination with Ginkgo, as the herb slows down blood clotting and increases the chance of bleeding.
Ginseng
Ginseng is used to increase energy by stimulating the adrenal gland, to reduce stress, boost the immune system and lower blood sugar. Warfarin reacts dangerously with Ginseng because its effect is reduced by the herb. When used with medication for depression like Nardil and Parnate, patients can become over stimulated and anxious and suffer from insomnia. When taken with diabetes medication, ginseng lowers blood sugar even further.
In conclusion, whether taking these popular herbal supplements, or any other, patients need to tell their physicians that they are consuming them, and report any side effects they may experience once they start taking a drug. Physicians will need to stay up to date with the latest research news on all herbal supplements.
References:
1. Dr. Lucinda Miller – “Herbal Medicinals”, Archives of Internal Medicine, 1998.
2. Bartram Thomas – Bartram’s Encyclopedia of Herbal Medicine, Marlow & Company New York.
3. Schuyler W. Lininger Jr. DC, Gaby Alan R MD, Austin Steve ND, Batz Forrest PharmD, Yarnell Eric ND, Brown Donald J ND, Constantine George RPh, PhD – A-Z Guide to Drug-Herb-Vitamin Interactions, Healthnotes Prima Publishing California
