Herbal brchure1

Medicines Interactions

TCAM Research Section Zayed Complex for Herbal Research & Traditional Medicine - WHO Collaborating Centre DPH & P - Health Authority, Abu Dhabi

ABSTRACT

Herbal medicinal products are being used by increasing number of people.

Often such products are taken concurrently with synthetic modern medicines, frequently without the knowledge of healthcare professionals.

Herbal medicines may mimic, decrease, or increase the action of prescribed allopathic drugs. The incidence of interactions between herbal medicines with the allopathic drugs is not yet fully known, and there is no body of reliable information to draw upon to assess the scale of possible problems or predict the clinical outcomes. The lack of evidence may be due to underreporting or unrecognized interactions. Some herbs can have a significant influence on concurrently administered modern drugs. As more evidence becomes available, there is an increasing awareness of the nature and potential of interactions between allopathic drugs and herbal medicines.

This can be especially important for drugs with narrow therapeutic windows and in sensitive patient populations such as older adults, the chronically ill, and those with compromised immune systems. Interactions of herbal and allopathic medicine are not predictable, but are possible, especially if we consider a range of allopathic prescriptions and herbal remedies. So, it is wise to play it safe and study the herbal medicine before adding it to our pillbox.

Keywords: Herbal medicines; Medicinal uses; Chemical constituents; Side effects; Contraindications; Bleeding risk

INTRO DUCTION ALFALFA In the present scenario, the demand for herbal medicine is growing exponentially throughout the world during last few decades. According to statistics from the WHO, over 80% of the world’s population (approx. 7 billion people) currently uses natural medicines, including herbal medicines, for some form of health care. Any medicine - herbal or otherwise - has the potential to have adverse effects (or side effects). Many plants can be poisonous to humans, and many phytomedicines have been developed from plants using the powerful compounds they contain. Hence it is needed to have an understanding of the risks posed by herbal products to ensure that such products are used safely. Reports of adverse effects in combining herbal medicines and conventional drugs bring up the need for safety monitoring and understanding of such treatment. For instance, if used beyond 8 weeks, Echinacea can cause hepatotoxicity and therefore should not be used with other known hepatoxic drugs, such as anabolic steroids, amiodarone, methotrexate, and ketoconazole. It is paramount for clinicians to be aware of known or potential drug-herb interactions to adequately treat their patients. The selection criteria for this article were: relatively commonly used herbs and herbs with known or potential drug-herb interactions.

ABBREVIATIONS CI: Contra Indication; SE: Side Effects; INR: International Normalization Ratio (i.e. bleeding risk)

ALFALFA

Name of Herb: Scientific Name/family: Medicinal Uses:

Alfalfa Medicago sativa L. (Fabaceae) Alfalfa is a legu me that has a long history of dietary and medicinal uses. Alfalfa seeds, when germinated, are popular as salad sprouts.

Therapeutic properties of alfalfa include lowering blood cholesterol and oestrogenic activity (Williamson et al., 2009).

Constituents:

Isolavones are the main active constituents of alfalfa including biochanin A, formononetin, daidzein and genistein. Saponins are glycosides of soyasapogenols A-E, and bi- and tri-desmosides of acidic oleanenes (medicagenic acid, hederagenin) esterified by an oligosaccharide, coumarins and miscellaneous compounds including vitamins, alkaloids, sugars, minerals and trace elements (Bruneton, 1999).

Possible Side Effects:

With cholesterol allopathic medicines, this herb may further lower the lipid levels. Cyclosporine/steroids make the herb immunostimulating. With hypoglycemic allopathic medicines, this herbal medicine may cause further hypoglycemia. Warfarin may increase bleeding risk, as the herb may contain warfarin constituents. Contraindication (C I: Lupus) i.e., side effect (SE): Pancytopenia and worsening of lupus (Jensen, 2003).

Aloe Vera

Name of Herb: Scientific Name/family: Medicinal Uses:

Aloe vera Aloe vera (L.) Burm.f. (Aloaceae) Aloe vera is used topically to heal wounds and for various skin conditions, including sunburn and is used in many cosmetic preparations such as moisturizers. It is reported to possess antiinflammatory, antitumor, immunomodulatory and antibacterial properties (Williamson et al., 2009).

Constituents:

The principal constituent of the gel are polysaccharides consisting mainly of polymannans, of which acemanan is the major one. Other constituents are pentosides-barbaloin, isobarbaloin, betabarbaloin and aloin (Evans, 1996).

Possible Side Effects:

Cardiac glycosides dioxin and thiazide diuretics along with this herb increase cardiac toxicity due to electrolyte imbalance and hypokalemia. The herb can potentiate drug toxicity; not recommended with breast feeding SE: (Jenson, 2003).