August 6, 1999

Herbal extracts and other alternative therapies are increasingly playing a role in the treatment of psychiatric disorders, but few psychiatrists are prepared to answer the questions posed by patients regarding their use, according to panelists at an APA annual meeting symposium on alternative treatments for depression and anxiety held in Washington, D.C., in May.

A survey published in the Journal of the American Medical Association in November 1998 revealed that total spending for alternative treatments in the United States rose from $14.6 billion in 1990 to $21.2 billion in 1997. The totals included not only herbs and dietary supplements, but other interventions such as acupuncture, chiropractic, hypnosis, homeopathy, and energy healing. The same survey found that visits to alternative practitioners rose from 427 million in 1990 to 629 million in 1997, while visits to all primary care physicians during the same period actually declined slightly from about 388 million to 386 million. Use of herbal remedies increased 380 percent during that period.

These trends may be having a greater impact on psychiatry than clinicians realize, according to surveys conducted by panelists Jonathan R.T. Davidson, M.D., a professor of psychiatry at Duke University Medical Center in Durham, N.C., and his colleague Kathryn Connor, M.D., an assistant research professor in the department at Duke. In a survey now in press in the Journal of Nervous and Mental Disease, Connor found that 44 percent of a sample of 213 patients who sought outpatient psychiatric care in North Carolina had used some form of alternative treatment for a psychiatric disorder in the preceding year. Half of those with a psychiatric diagnosis suffered from an anxiety disorder, and half of those with an anxiety disorder had used an alternative treatment. Connor found that the most common alternatives for psychiatric disorders were meditation and spiritual therapy, followed by herbal therapy.

Of the patients who said they had used an alternative treatment in the prior year, nearly three-fourths reported using it more than 10 times, said Connor. "If someone's going to use it, they are going to give it a good try," she noted. More than three-fourths of those taking herbal extracts for either psychiatric or physical problems reported "at least much, if not very much, improvement," she added. One-fourth of those who used an alternative treatment for a psychiatric problem said they found it more effective than conventional treatment, while slightly fewer than half said it was equally effective.

Asked why they chose alternative treatments, respondents cited fewer side effects and a "sense of control, didn't need to see a doctor, could do it own their own," Connor said. Respondents also said they liked using "natural" products, although the term was not defined. The biggest disadvantage cited was lack of scientific data, and despite the overall satisfaction with alternative therapies, 90 percent of those surveyed said they wanted more information.

Psychiatrists and other physicians should "bear this in mind in treating our patients," said Connor. Alternative treatments "may have benefits in and of themselves, but can also impact on the other treatments we may be administering" to patients.

In addition to asking patients about their use of prescription and over-the-counter drugs, clinicians should routinely inquire about patients' use of herbal preparations and dietary supplements at the start of treatment and at follow-up, said Connor. "Unfortunately, patients often do not think of herbs and dietary supplements as medications," she noted.

In his survey, Davidson found higher rates of psychiatric disorders in patients who had visited alternative practitioners in the U.S. and the United Kingdom. He found that 25 percent had an anxiety disorder and 12 percent an affective disorder. This contrasted with average rates in primary care of between 10 percent and 15 percent prevalence for anxiety disorders and 10 percent prevalence for affective disorders.

The growth in use of herbs has been led by psychotropic herbs, with St. John's Wort for depression at the top of the list. Other popular psychotropic herbs include calmatives such as kava and valerian, and gingko to enhance memory in patients with dementia. From 1990 to 1997, use of St. John's Wort grew by 2600 percent, use of kava by 473 percent, and use of gingko by 140 percent, said Davidson.

There is evidence that St. John's Wort is quite effective in mild to moderate depression, said Davidson, quoting a number of published studies. He is currently conducting research on St. John's Wort as the principal investigator for a nationwide, multicenter trial funded by the National Institute of Mental Health. The herb may also be helpful in dysthymia and seasonal affective disorder, he commented.

"At the moment it would not be recommended treatment for suicidal patients, for depressed bipolar [patients], or for severe recurrent depression requiring long-term treatment," he advised. Absent specific data, use in pregnancy should generally be avoided, said Davidson. Use with monoamine oxidase inhibitors should be avoided, but adjunctive use with selective serotonin reuptake inhibitors is acceptable, he said.

The mechanism by which St. John's Wort works is unclear, observed Davidson. It is not a monoamine oxidase inhibitor, but does affect a variety of other neurotransmitters. It modulates gamma amino butyric acid (GABA) and causes "simultaneous and roughly equal reuptake inhibition of serotonin, norepinephrine, and dopamine," he noted. In its multiple actions, St. John's Wort is extremely unusual, and among synthetic antidepressants, only venlafaxine inhibits multiple neurotransmitters, he noted.

"We really don't know which one or ones of these mechanisms could explain the antidepressant effects of St. John's Wort," said Davidson. "But at least there is a credible basis; it's not just magic."

Scientists have yet to understand how and why St. John's Wort and other plant preparations work, observed panelist Jerry Cott, Ph.D., chief of the adult psychopharmacology research program at the National Institute of Mental Health. Cott is currently on loan to the National Center on Complementary and Alternative Medicine at the National Institutes of Health.

There is confusion about dosing and a common misconception that St. John's Wort must be taken two or three times daily to be effective. But Davidson said that several active compounds identified in the herb have long half-lives, which suggests that once-daily dosing should be effective. Clinicians should start patients at 900 milligrams per day, but may boost the dose to 1800 milligrams daily if necessary, he said. If the drug is going to help a given patient, results will become evident in one to three weeks. He advised clinicians to read labels carefully and to seek a product standardized for hypericin.

Research suggests that St. John's Wort may be less potent an antidepressant than tricyclic drugs, said Davidson, "but on the other hand the side effects are definitely much less." The chief danger appears to be sensitivity to sunlight, which may accelerate burning or tanning, according to Davidson. If St. John's Wort has "a much better safety profile and much better patient acceptance" than synthetic antidepressants, the only question is whether it is sufficiently effective to grant it a significant role in psychiatry, said Davidson.

The Web address for the National Center on Complementary and Alternative Medicine is www.altmed.od.nih.gov/nccam.-R.B.K.