Ayahuasca and depression

Already has been mentioned and spoken about the serotonergic effect of ayahuasca and, even though when apparently all the studies carried out are not complete enough to provide scientific prove about the medicinal power of the sacred brew, in this text there will be exposed these researches with their very favourable results.


According to the current Diagnostic and Statistical Manual of Mental Disorders published by the American Psychiatric Association,

“the diagnosis of a depressive episode requires the presence of depressed mood and/or anhedonia (inability to feel pleasure in normally pleasurable activities) for a minimum of two weeks, accompanied by at least four of the following symptoms: significant weight loss or gain (5% of body weight); psychomotor agitation or retardation; insomnia or hypersomnia; fatigue or diminished energy; low self-esteem or inappropriate feelings of guilt; difficulties to think, concentrate or make decisions; and thoughts of death and suicide ideation or attempt. The symptoms must be associated with significant suffering and/or impairment in social, occupational or other functional areas, cannot be caused by a general medical condition or substance use, or fulfill the criteria for a mixed episode (episode in which the diagnostic criteria for both depression and mania are simultaneously satisfied)”.

Then, they can be divided into single episode, recurring or chronic, depending on the frequency and duration, and also classified in mild, moderate and severe in terms of severity. Environmental factors as childhood history of traumatic events, early parental loss, family and personal history of depression, genetic factors, personality traits and recent traumatic events are connected with the vulnerability of developing depression.

The discovery of antidepressants in the 1950s drastically transformed the treatment of depression and they still remain the leading strategy. Even though this discovery was accidental during the development of antihistamine and antituberculosis, it had led to the proposition of the monoamine theory of depression, according to which this disorder would be caused by decreased availability of noradrenaline and serotonin in the brain.

The first generation of antidepressants can be divided into tricyclics (TCA) and monoamine oxidase inhibitors (MAOI); both act by increasing extracellular levels of monoamines. Besides the therapeutic action, TCA acts on other receptors, leading to undesirable outcomes such as urinary retention, orthostatic hypotension, weight gain, constipation and somnolence. Given the low selectivity of classic antidepressants, newer ones were developed: selective serotonin reuptake inhibitors (SSRIs: fluoxetine, paroxetine, etc), selective noradrenaline reuptake inhibitors (reboxetine) and serotonin and norepinephrine reuptake inhibitors. There are even antidepressants with multiple action mechanisms, like mirtazapine and nefazodone. The newer antidepressants, such as SSRIs, have basically the same action mechanism as the first generation ones, for instance, they increase the level of monoamines in the brain, though they offer more safety: side effects, although milder, are still present and are specific to different classes of medications; for example, sexual dysfunction and gastrointestinal disorders are common to the SSRIs users and sleepiness and weight gain are associated  to mirtazapine users. Anyway, the limitations associated with the currently available pharmacological treatments of depression are: low response rates, side effects and time required until therapeutic effects are attained.

There are several anecdotal reports where the ritual use of ayahuasca is associated with the relief of depression. Thus far, all studies to date have demonstrated the safety of ayahuasca with reports of individuals who have used it for more than 30 years without evidence of harm to health.

Hoasca Project

This was the first in-depth study of the physical and psychological effects of ayahuasca in humans. In 1993 and for about a month, Dr Charles Grob, Dr Dennis McKenna and their team travelled to Manaus (Brazil) to study members of the União do Vegetal (UDV), church that uses ayahuasca as a sacrament, and to compare them to a control group that had never taken the brew.

The subjects were a group of 15 healthy men, volunteers, who had belonged to the UDV for at least 10 years and who had taken ayahuasca in ritual context an average of once every two weeks. None of them were actively using alcohol, tobacco or any drugs other than the sacramental tea. The control group was formed by 15 age-matched males recruited from among the friends of the subjects, also local residents having similar diets and socioeconomic status; none of them were members of the UDV nor ever ingested ayahuasca.

The team of the Hoasca Project ran the same tests to the volunteer subjects as to the control group. The researchers measured blood pressure, heart rate, pupil dilation, body temperature and used structured psychiatric interviews to get inside the participants´minds.

Many of the individuals had struggled with alcoholism and depression before joining the church and they all credited ayahuasca with the transformation, in some cases,”they felt like it had saved their lives.” The studies found that all the ayahuasca-using UDV members had experienced remission without recurrence of their addictions, depression, or anxiety disorders. Moreover, blood samples revealed that Ayahuasca seems to give users a greater sensitivity to serotonin—one of the mood-regulating chemical produced by the body—by increasing the number of serotonin receptors on nerve cells. Deficits in serotonin transporters are connected with alcoholism and depression — the same problems that the 15 subjects said the ayahuasca had helped cure.

Unlike most common anti-depressants, which can create such high levels of serotonin that cells may actually compensate by losing many of their serotonin receptors, the Hoasca Project showed that ayahuasca strongly enhances the body’s ability to absorb the serotonin that’s naturally there.

Evidence of health and safety in American members of Santo Daime religion

This is the first study to evaluate the health status of American members of Santo Daime religion.

Carried out in 2008, 32 out of 40 american members of one branch of the Santo Daime Church were interviewed providing demographic information, physical exam, drug use timeline, a variety of psychological measures (using measures of anxiety, panic and hopelessness), and data about childhood conduct disorder. Participants were asked about extent of Church participation, what is liked least and most about ayahuasca and what health benefits or harms they attribute to it. Physical exam and test scores revealed healthy subjects.

Members claimed psychological and physical benefits from ayahuasca. Ten of the 32 individuals described physical health improvements since joining the Church. Nineteen subjects were diagnosed with psychiatric disorders in their lifetime, with 6 in partial remission, 13 in full remission and 8 reporting induction of remission through Church participation. 24 subjects had drug or alcohol abuse or dependence histories with 22 in full remission and all 5 with prior alcohol dependence describing Church participation as the turning point in their recovery.

The authors found that those participants who were under the effects of ayahuasca had lower ratings of anxiety, panic and hopelessness, compared with participants receiving placebo.

Therapeutic trials with ayahuasca in humans

In 2011, Dr Rafael Guimaraes conducted an exploratory study involving three female participants with a clinical diagnosis of recurring depressive disorder and current mild/severe depressive episode, without psychotic symptoms, who have had no success with at least one common antidepressants. The subjects had not been in treatment with antidepressants for two weeks and received an oral and very mild dose of 2ml/kg of Aya and their mental state has been assessed by means of psychiatric scales 10 minutes before to the ayahuasca administration and 40, 80, 140 and 180 minutes after and also on days 1, 2, 7, 14 and 28 after the intake. Starting at 40 minutes after drinking the tea and over time, it could be seen a significant decrease in the scores, pointing out a reduction in depressive symptoms, beyond of episode severity. This reduction is sustained from day 1 to day 14; the researchers observed reduced depression in all participants within two to three hours of ingesting the substance, and also after a three-week follow-up. The items that observed greatest variations during the experiment were those related to depressed mood, guilt feelings, suicidal ideation, difficulties with work activities, psychic anxiety and genital symptoms.

Even though this study is not complete since there was no placebo/control group and only based on a very small group, the most important remark is that ayahuasca´s positive effects on individuals with depressive disorders starts to be noticeable after 40 minutes of the intake, when traditional antidepressants need of at least 3 weeks to verify their results.

For further information, it´s recommendable the personal testimony from a journalist about how she cured her depression with ayahuasca at  http://www.kirasalak.com/Ayahuasca.html.