Adverse Reactions to Alternative Medicines While complementary alternative medicines (cam) are often considered to be safe, side-effects and allergic reactions may occur



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Adverse Reactions to Alternative Medicines
While complementary alternative medicines (CAM) are often considered to be safe, side-effects and allergic reactions may occur. Allergic reactions to CAM are most common in people with other allergic diseases, such as asthma or hay fever. These people are often sensitive to many allergens, including those in herbal medicines.
Adverse interactions with CAM and drug treatments can occur

Many adults and children in the US use CAM to treat or prevent various ailments. Some people use these together with medications prescribed by their doctor.


Regardless of your decision in this regard, it is important to let your doctor know if you are taking

CAM. This is because side effects from some CAM may occur, and because some CAM may

interfere with the action of conventional medications can occur. It is also important to realize that

CAM have not been subjected to the rigorous study undertaken with conventional medicines.


Many herbal medicines are made from Asteraceae flowering plants

The Asteraceae are common flowering plants. Exposure to these plants is common and hard to

avoid. Pollen from Asteraceae plants are an important cause of hay fever and asthma. These

plants are sometimes used as herbal medicines. Asteraceae plants include:

__ FLOWERING PLANTS such as chrysanthemums, dahlias, sunflowers, marigolds,

safflower and daisies – the pollen from Chrysanthemum and sunflower cause symptoms

in some people who are exposed to heavy concentrations, such as flower growers.

__ EDIBLE PLANTS such as lettuce, safflower, chicory and artichoke

__ WEEDS such as Ambrosia (ragweed) species, Artemisia (mugwort, sagebrush,



wormwood) species, Parthenium (feverfew) – the pollen from these plants are important

causes of hay fever and asthma

__ CAM such as Echinacea, dandelion, chamomile, feverfew, milk thistle and wormwood.
Cross-reactivity may explain allergic reactions to CAM and some foods

Some people sensitive to substances in pollen will also be sensitive to similar substances present in

other plants, like raw or semi-cooked fruit or vegetables. This is known as “cross-reactivity". One

of the most common examples is "oral allergy syndrome". In this condition, itching and swelling of

the mouth and tongue occurs, usually after eating uncooked or semi-cooked fruit. Most of those

affected have other allergies like asthma or hay fever, and are sensitive to pollen allergens.

Sensitization to Asteraceae pollen has also been linked with allergic reactions to plant-derived CAM

such as Echinacea, Royal Jelly, bee pollen extracts and chamomile, as well as foods like celery,



honey, sunflower seeds, carrot, lettuce, watermelon and nuts.
Allergic reactions to Echinacea can be severe

Echinacea (from the Asteraceae group of plants) is a popular herbal remedy in the US, with

around 1 in 20 people taking it in any one year. Over two-dozen allergic reactions to Echinacea had been described in the US by the end of 2000 (Mullins and Heddle, 2002). Reactions included

anaphylaxis (the most severe type of allergic reaction), acute asthma attacks, severe hives and

swelling. Four were hospitalized and Echinacea was the only implicated medication in 15 cases.

Over half were known to have other allergies. Many reactions occurred after their first ever known

dose.
Other adverse reactions to Echinacea

Burning or stinging of the tongue is a common experience. Injections of Echinacea can cause

shivering, fever and muscle weakness. Hepatitis has also been described. Other symptoms

reported include rashes, delayed asthmatic reactions, muscle aches and pains and stomach upset.
Contact allergic dermatitis

Asteraceae plants may cause contact allergic dermatitis. Echinacea, daisies, chrysanthenum,

chamomile, tansy, dandelion, feverfew and sunflowers have all been associated with contact allergy in

gardeners and florists. Similar symptoms can be caused by plant extracts in cosmetics, shampoos

and massage oils. Contact with airborne plant-derived allergen can also trigger rashes in exposed

skin, a condition commonly known as "n bush dermatitis".
Use of Asteraceae containing CAM in pregnancy may be unwise

Few published studies have looked at the safety of CAM during pregnancy or lactation. This is an

important issue, as up to 1 in 6 pregnant women in the developed world use these medications.

Unfortunately, toxicity (such as a baby born with lead poisoning) and serious allergic reactions

(such as to chamomile) have been described. Only one very small study of 206 pregnant Canadian women has examined whether Echinacea is safe to use during pregnancy. While no adverse reactions were noted, this study only had the power to detect a major cause of deformities. The properties of some other Asteraceae plants suggest they should be avoided. For example, feverfew can trigger pregnancy loss in cattle and stimulate uterine contractions in pregnant women. Chamomile causes malformations in animal studies. Safflower, tansy, feverfew, calendula, chamomile, yarrow, milk thistle and wormwood promote menstruation, stimulate uterine

contraction and can trigger abortions in animals (Ernst, 2002a; Newall et al., 1996). Taken together with the potential for allergic reactions, the safety of Asteraceae-containing CAM during pregnancy is unknown.


Drug interactions, contraindications and precautions

One in 5 people in Canada and the USA use prescription drugs at the same time as CAM.

The risk of adverse events is increased if the CAM has drug-like activity or interferes with the way in which the body deals with these drugs. For example, some liver enzymes play a major role in drug breakdown and “detoxification” by the liver. Echinacea, milk thistle and chamomile can interfere with some of these enzymes and increase or decrease the effects of some medications> This can lead to increased side-effects or reduced benefit from taking these medicines.

Feverfew has aspirin-like activity and may increase the risk of bleeding while taking blood thinners

like warfarin or aspirin. Chamomile contains natural warfarin-like “coumarins” which increase the

risk of bleeding in those taking warfarin as a medication.

Because of the claim that Echinacea has a short-term stimulatory effect on the immune system,



some authorities recommend that Echinacea be avoided in patients with autoimmune disease (eg. lupus, multiple sclerosis), or in those with chronic HIV/AIDS infection or TB/tuberculosis. For similar reasons, it is commonly recommended that Echinacea be avoided in patients undergoing organ transplantation, to reduce the risk of rejection. Similarly, Echinacea is thought to inhibit wound healing and should be avoided if surgery will be performed in the near future.


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