It has long been suspected that regular use of cannabis (marijuana), especially the high potency variant called ‘skunk’, can increase the risk of psychosis in vulnerable people.
And now Sir Robin Murray, professor of psychiatric research at King’s College London, rightly says, ‘It’s not sensible to wait for absolute proof that cannabis is a component cause of psychosis.’ He adds, ‘There’s already ample evidence to warrant public education around the risks of heavy use of cannabis, particularly the high-potency varieties. For many reasons, we should have public warnings.’
This view is echoed by a government spokesperson: ‘We must prevent drug use in our communities and help people who are dependent to recover, while ensuring our drugs laws are enforced. There is clear scientific and medical evidence that cannabis is a harmful drug which can damage people’s mental and physical health, and harms communities.’ (The Guardian, 15 April 2016.)
With this preamble, let me get to my theme: the treatment of depression.
There is no doubt that in extreme cases the illness called major depressive disorder can be devastating. I have seen patients reduced to a state of complete immobility, unable to work or even get out of bed because of overwhelming unhappiness. These, however, are a minority. The vast majority of people who have been labelled as suffering from a depressive ‘disorder’ have what might better be called normal human misery.
There are no blood tests or other objective criteria for making the diagnosis; it is made entirely on symptoms or observations such as these:
Depressed mood most of the day, nearly every day…Markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day…Significant weight loss when not dieting or weight gain…Insomnia or hypersomnia (excessive sleepiness) nearly every day…agitation…Feelings of worthlessness or excessive or inappropriate guilt…Diminished ability to think or concentrate…Recurrent thoughts of death…recurrent suicidal ideation…or a suicide attempt or a specific plan for committing suicide…(Diagnostic and Statistical Manual of Mental Disorders, 5th edition, 2013, American Psychiatric Association.)
These are pretty serious symptoms, but they are all subjective and need to be interpreted. How do you decide when a symptom is ‘marked’ or ‘significant’? There is a risk that people suffering from normal extreme sadness, such as after a bereavement, may be misdiagnosed as having a depressive disorder because the symptoms have lasted longer than the American Psychiatric Association deems appropriate. (There is a whole book dealing with this very problem: The Loss of Sadness: How Psychiatry Transformed Normal Sorrow into Depressive Disorder, by A V Horwitz and J C Wakefield, OUP 2007.)
Such a view is echoed in an article on this same problem in The British Medical Journal (9 December 2013) on medicalising unhappiness which noted:
Over recent decades there has been an increasing tendency, especially in primary care, to diagnose depression (commonly major depressive disorder) in patients presenting with sadness or distress and offer them antidepressant medication.
Many patients report sadness or distress during consultations with primary care doctors. Such emotions may be related to grief and other life stresses, including the stress of physical illness. Sometimes sadness appears out of the blue, without obvious relation to external causes.
Without a doubt, depression is real and horrible and deserving of the highest standards of medical care.
What to do about it? Rather than reaching for the prescription pad, it might be better to listen to the patient. He or she, if given the chance in a supportive, non-judgemental environment, nearly always has got plenty to say – attesting to the importance of the psychological causes of depression.
If the doctor does decide a prescription is warranted, it should be understood by both parties that this is empirical treatment. The fond idea that antidepressant correct a chemical imbalance in the brain is purely hypothetical. Such imbalances, if they exist, could well be the result rather than the cause of the depression. Antidepressants, nonetheless, can be helpful to tide a patient over a difficult patch, but they are not a cure. Do they work? They appear to work in some people, but it is unpredictable. Some patients, especially those with more severe degrees of depression, may find it preferable to be in the drugged state which antidepressants induce than to suffer their unmedicated distressing feelings; the same applies to people with severe anxiety and agitation.
Further, psychiatrists, although their skills may be helpful in choosing a drug for those patients whose unhappiness is deemed serious enough to give it a try, should not be under any illusions about what they are doing. Antidepressants do not cure depression. At best they can help to reduce symptoms and thereby make life easier to bear.
This is all the more relevant in the light of a recent study on depression reported in The Lancet Psychiatry that there is a drug which is consistently effective in 35-40% of patients: it is called placebo.
Text © Gabriel Symonds
This entry was posted in Depression, Psychiatry and tagged antidepressants, cannabis, marijuana, placebo, psychosis, Sir Robin Murray, The Loss of Sadness on November 27, 2016 by Gabriel Symonds. Edit