Do 'old' stimulant drugs have a role in managing treatment-resistant depression?

A new study supports the role of the 'old' psychostimulant antidepressant drugs for those patients with melancholic and bipolar depressions who are treatment resistant or who have had significant side-effects to previous or current antidepressant medications.

These older antidepressants, methylphenidate and dexamphetamine, have been largely neglected in recent decades, due to concerns about efficacy, tolerance and dependence.

But in this study, conducted by researchers Professor Gordon Parker and Dr Heather Brotchie from the Black Dog Institute, there were distinctive clinical benefits for a significant percentage from these psychostimulant drugs – evaluated in a sample of 50 patients (60 percent female and with an average age of 49 years).

The study has been published in the latest internationally renowned psychiatric journal, Acta Psychiatrica Scandinavica.

"Two-thirds of these patients with treatment-resistant depressive conditions benefited from a psychostimulant prescribed as monotherapy or as an augmenting drug – while side-effects were uncommon and generally slight", said the Professor.

"While there was no argument for psychostimulants challenging the use of more orthodox antidepressants, their main advantages may be their ability to act quickly, and that they reduce fatigue (a depressive symptom that can be slow to respond to orthodox antidepressants)."

Professor Parker said the study also revealed that these older antidepressants often worked at quite low doses.

Though the observations in this clinical study showed benefits for patients with melancholic and bipolar depression who have failed to respond to orthodox antidepressant drugs or had experienced significant side-effects, Professor Parker said that formalised placebo-controlled studies were now needed to test these results further.

He said that, despite the limitations of the study, he expected psychiatrists to show a lot of interest in revisiting the use of these older drugs in such difficult to treat conditions.

At the present time, psychiatrists need to apply to the Department of Health in writing to obtain permission to use dexamphetamine and methylphenidate. Professor Parker believed this practice should largely remain in place to lower their risk as 'street-drugs', but possibly allow mood disorder specialists freer access as occurs for ADHD prescribers.

(Source: Black Dog Institute: Acta Psychiatrica Scandinavica: April 2010)