by Dr.Greg Sperber, BMBS, DAOM, LAc

Recently, my patients have been more resistant to taking herbs. The concerns of quality in China manufacturing in addition to a regular onslaught from the medical profession and the media about drug-herb interactions have combined to make many consumers wary. However, combining herbs and drugs is quite safe. It has been done for decades in China, and in reality, only a very few combinations, occasionally, have been shown to have a true interaction. Of course, there are steps to prevent known and predict unknown negative mixtures.

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1. Know and understand what drugs your patients are taking. This means looking up each individual drug and understanding how it works and why the patient is on it.
It is also important to ask if the drugs are achieving their intended purpose. In addition, ask your patient for written permission to discuss their case with their doctor.

2. Know what herbs you want to prescribe to your patients. Do your normal history, exam, and diagnosis, and determine what herbs your want to prescribe. It is important to follow your training and construct an her-bal formula that will maximize your patient's benefits.

3. Find out if there are any known interactions between the drugs and the herbs. There are several ways to do this. Put the drug's and herb's names into Google Scholar (http://scholar.google.com). Check out one of several books (including mine, of course) that list interactions. Or soon, you may go to www.integrativepharm.com and plug in either a drug or an herb to see their interactions.

4. Determine if there are any theoretical interactions. The best way to accomplish this is to have some basic knowledge of fundamental pharmacology.
Essentially this means understanding the ADME scheme and the therapeutic index (also known as the therapeutic margin or window).

The ADME scheme encompasses how a drug interacts with the body and includes absorption, distribution, metabolism, and elimination.
An herb can interact with a drug and vice versa and affect any of these areas. For example, taking a drug that reduces acidity, such as a proton pump inhibitor or H2 histamine antagonist, could cause difficult digestion of a cloying herb such as shu or sheng di huang (prepared or fresh rehmannia). There are two big issues within the ADME scheme. The first is within distribution. Protein binding within the blood is necessary for many drugs and herb components to get to their site of action. If a drug or herb interferes with protein binding, much more of it could be available to the body and cause an overdose scenario. The second issue involves metabolism.
Cytochrome P450 (CYP) is the most common enzyme within the liver used to convert a drug or herb constituent into another chemical. Interference at one or more subtypes of this enzyme could cause more or less of a constituent to be available to the body and therefore may cause an overdose or under-dose. Unfortunately, while both protein binding and CYP interactions are well known for most drugs, neither has been well- studied in herbs.

Finally, the therapeutic index is an indication of the difference between a helpful dose and a harmful one. Any drug with a narrow therapeutic index, or in the case of herbs, those that are "toxic,"
could be shoved into dangerous territory with minor interactions.
Fortunately, there aren't a lot of drugs that have a narrow therapeutic index. These include lithium (LithabidR), phenytoin (DilantinR), the cardiac glycosides (digoxin and digitoxin, LanoxinR), warfarin (CoumadinR), theophylline, and the entire class of tricyclic antidepressants (including ElavilR).

5. If there are any known or potential interactions, try to find an alternative. While we have little or no control over the pharmaceuticals our patients are taking, we can look at the herbs we want to prescribe and potentially change them to safer, similar herbs, or take them out of the formula completely.

6. Once the formula has been determined and risks are minimized, prescribe the herbs at minimal levels and slowly increase the dose.
In this way, even if there is an interaction, we can minimize its impact and prevent serious consequences. Start with a small dose for a couple of days, discuss them with the patient, and then increase the dose, if there are no negative reactions. Continue to slowly increase until the desired dose is achieved. This can take a couple of weeks. Remember to take into account the age, weight, and condition of the patient.

7. Maintain contact with the patient. It is always a good idea to check in with the patient and make sure there are no adverse reactions. In addition, it is very important that the patient can reach the prescriber at any time, in some way, in the case of an emergency or perceived emergency.

These seven steps should protect the patient who is taking a combination of pharmaceutical drugs and herbs. Discussing or making a brochure with these steps can allay a patient's fears about interactions. This means better herbal compliance and better outcomes for your patients. While the media and medical establishment have greatly overblown fears about combining herbs with drugs, there are some real interactions and basic prudence is warranted. By following these steps, any potential problems will be minimized.