Central  South  Dakota  Medical News
The Clinical View
  by P.E. Hoffsten, M.D.
15 October 2003

ST. JOHN’S WART – PRECAUTIONS

      One of the most widely utilized anti-depression medications is St. John’s Wort.  This is available without a prescription and sold actually as a nutritional supplement.  Thus there are no regulations regarding the purity of the drug and the manufacturer and sales personnel can make no claims regarding medicinal effects.  Be that as it may, it is one of the most used utilized medications for depression.

     Recently, there was a multicenter, double blind, placebo controlled study done demonstrating that St. John’s Wort had no beneficial effect greater than that of a sugar pill.  What does all this mean?  The first words used were “multicenter”.  This means that several large medical centers around the country cooperated in a study to evaluate the drug.  What does “double blind” mean?  Columnists often make jokes that it means both the patient and the health care provider were blind.  It really means that half the patients were given a sugar pill that had no effect and half the patients were given St. John’s Wort and neither group knew which pill they were getting.  What does “placebo controlled” mean?  This means that St. John’s Wort was compared to a pill that had no effect, kind of like a sugar pill.  Sometimes, one drug is compared to another drug to see which one is better.  But in this case St. John’s Wort was compared to a nothing drug to see if St. John’s Wort had any demonstrable effect.

     When the study was completed, there was no difference in the response of the group that got the sugar pill and the group that got St. John’s Wort.  If a drug company were to submit a study such as this to get approval for a cholesterol drug or a blood pressure pill or a diabetes pill, the FDA would not approve the introduction of the new pill for the market because it had no demonstrable effect.  Thus, St. John’s Wart cannot be approved by the FDA as a prescription medication.

     Beyond St. John’s Wart having no demonstrated beneficial effect for depression, a recent article was published showing some of the harm this drug can do.  To begin with, all drugs that a person takes must be processed and disposed of by the body.  The liver is the primary site where this activity is carried out for most drugs.  The liver has a very complex set of machines that processes drugs and excretes them into the bile and out into the stool.  Different people have different rates at which they get rid of drugs.  Some people are called “fast metabolizers” and some people are called “ slow metabolizers”.  One person maybe very fast for certain drugs and very slow for others.  Just as your fingerprints and the color of your hair are different from person to the next, the rate at which you metabolize medications is highly variable.

     The article that was recently published in the September 17th issue of the Journal of the American Medical Association looked at effect St. John’s Wart had on the rate at which a person metabolized and got rid of a drug.  It was found that St. John’s Wart markedly increased the rate at which certain drugs were gotten rid of.

 Now imagine this.  A lady is taking birth control pills with a product called ethinyl estradiol.  She is doing this to prevent an unwanted pregnancies.  It is working very well.  She hasn’t gotten pregnant but she starts taking St. John’s Wort for reasons of her own, presumably depression.  The St. John’s Wort increases the rate at which she gets rid of the ethinyl estradiol in her birth control pill.  Now there is not enough to prevent a pregnancy and she gets a cute little surprise.  The natural reaction is to fault of the birth control pill.  The real answer is the St. John’s Wort fixed it so that her rate of getting rid of her birth control pill was too fast and it no longer protected her from an unexpected or perhaps unwanted pregnancy.

     In the article that was published in the Journal of the American Medical Association last month, it was noted that there was a certain machinery set in the liver that was accelerated by St. John’s Wart.  Diabolically, that set of machinery is the one that gets rid of at least one half of all the drugs that come into the body.  Drugs that are affected would include simvastatin  which is used to keep cholesterol down.  By taking St. John’s Wort with simvastatin (Zocor) the effectiveness of the Zocor is decreased.  Second, there is a drug called Digoxin (Lanoxin) that is an important heart pill.  The rate at which this drug is gotten rid of is accelerated by St. John’s Wort.  Suppose you are using Allegra (fexofenadine) to treat your allergies.  If you are using St. John’s Wort at the same time, the effectiveness of the Allegra is markedly decreased.  A really dangerous situation arises in those patients that have had a transplant of a kidney or a heart or a lung and are taking medications to keep them from rejecting their transplant.  St. John’s Wort accelerates the rate at which their anti-rejection medications are gotten rid of and can cause a person to reject their transplant.

     Lastly, those of you who are using Xanax (alprazolam) to help with anxiety or sleep will have a decreased effectiveness of the alprazolam because of St. John’s Wort.  Notice that Xanax and St. John’s Wort would be used in the same population of people who are depressed.

     In closing, I imagine I am going to get accused of self serving here.  I don’t do my own plumbing and have been advised that I should never again try to wire the lights in my basement.  I don’t try to fix my own car, or stove, or dishwasher.  I continue to be amazed at how much trouble people get into trying to be their own health care provider.  Granting that you have to take care of you, the internet and the lay press are just not that reliable.  That is the reason that multicentered, double blind, placebo controlled trials are required by the Food and Drug Administration before a medication is allowed out on the market by prescription.