A new treatment option could help the more than 250,000 Canadians living with schizophrenia — but few may be able to get it.

Austin Mardon was a daring, young explorer working for NASA in Antarctica when he developed schizophrenia at age 30.

"It was as St. John of the Cross talks about, the dark night of my soul," he recalled.

The side-effects of the tablet-form of Risperdal caused Mardon to gain weight and sleep a lot; constipation and sexual dysfunction are also possible.

Studies show three-quarters of people with schizophrenia go off their oral medication at some point, partly because of the side-effects.

"As a consequence of that, people will often end up being in hospital; they may make an attempt on their lives, may become aggressive," said Dr. Pierre Chue, a psychiatrist in Edmonton.

Fewer side-effects

A new, slow-release formula of Risperdal provides a constant level of medication for two weeks, with fewer side-effects than tablets, according to a clinical trial of the injectable version of the drug.

The advantage of the long-acting drug is that people tend to take it consistently, and doctors know immediately when a dose has been missed, said Chue, who has led several studies on the drug.

"We don't have full reimbursement in every province across Canada, which I think is the reason why it's not widely used," Chue said.

Cost is the roadblock to expanding access: At $400 a month, the injection medication is four times the price of the tablet form.

"The logistics of a lot of the programs mean that we spend a lot of time filling out forms and waiting for coverage that would be better spent working with the patient themselves," said Wendy Wood of the Centre for Addictions and Mental Health in Toronto.

Relapse rates halved

In the long term, doctors said, the injectable form will save money, since those on it have half the rate of relapse and hospitalization.

The direct cost of treating schizophrenia totals $2 billion a year, plus another $5 billion in lost productivity, researchers at McMaster University in Hamilton, Ont., found in 2004.

Mardon was able to get the drug through a clinical trial. The researcher, who is now polishing an article for a scientific journal, said he feels like a gentler person than before.

"It has made an incredible difference," said Mardon, who gets the drug through a clinical trial. "I've become married; I've written 12 papers."

When the clinical trial ends, there are no guarantees the provincial drug plan will pay for the treatment.