A West Australian former soldier has spoken out over fears an anti-malaria drug he took as part of a pharmaceutical trial while serving has left him with a permanent and debilitating brain injury.

Former rifleman Mathew Emerson came forward after another high-ranking currently serving soldier gave evidence at a Senate inquiry last week, detailing concerns hundreds of soldiers may have suffered severe long-term side effects from the drug mefloquine, including depression, anxiety, vertigo, nightmares and suicidal thoughts.

Mr Emerson, 35, said his battalion was offered the choice of mefloquine, marketed as Lariam, or the older more established drug doxycycline, prior to a planned deployment to East Timor in 2001.

"They said 'it's got less side effects than doxycycline, and you only need to take it once a week', so most of the people I knew decided to take the mefloquine," he said.

"I felt perfectly safe and that the Army had my life as their best interest. They trained me, they're meant to look after me, but in this case, they didn't."

Mefloquine use in Australia Mefloquine approved for use by Australian Therapeutic Goods Administration (TGA) in 1993

Mefloquine approved for use by Australian Therapeutic Goods Administration (TGA) in 1993 Drug's factsheet from manufacturer Roche notes neuropsychiatric effects including anxiety, paranoia, depression and psychotic behaviour have been reported to occur long after the drug has ceased to be taken

Drug's factsheet from manufacturer Roche notes neuropsychiatric effects including anxiety, paranoia, depression and psychotic behaviour have been reported to occur long after the drug has ceased to be taken The ADF continues to prescribe mefloquine, but says it is a "third-line agent", and only used when one of two other TGA-approved medications are not appropriate

The ADF continues to prescribe mefloquine, but says it is a "third-line agent", and only used when one of two other TGA-approved medications are not appropriate ADF says prescriptions have averaged 25 per year for the past five years

He said he was told to sign a consent form, and that if he did not sign it he could not deploy.

He stopped taking the drug after experiencing nausea, but then was placed back on it for another five weeks.

In 2003, Mr Emerson said he started to "go downhill" mentally.

"I started to feel depressed. I wanted to kill myself, had constant thoughts about it," he said.

"I went to see the Army psychiatrists, and it sounded stupid when I went to say the words so I didn't say anything, I just kept my mouth shut.

"I put on a rosy exterior, just tried to keep a smile on my face all the time."

He also started having nightmares and outbursts of anger, and in 2004 had a complete nervous breakdown where he woke up in hospital with no memory of the previous few days, despite being conscious and alert during that time.

Medical discharge ends dream of Army career

In November 2005 Mr Emerson was discharged on medical grounds, a huge blow to a man who grew up always knowing he would serve in the Australian armed forces.

"It's something I wanted since I was a kid," he said.

"I used to dress up as a soldier when I was eight years old and run around.

"I was brought up in an Army family, so all my friends were Army.

"I guess it's just where I was destined to go ... that's what I was going to do as a career for the rest of my life.

"I've been gutted for years about it.

"But I'd recommend to anyone to do it (military service). It's the best time I had in my life."

After his discharge, Mr Emerson continued to develop symptoms, including vertigo, hearing issues and significant depression.

He struggled to hold down a job and at one point was confined to bed for a month as his vertigo got so bad he could not walk.

Mathew Emerson wants the Defence Force to reach out to people involved in anti-malaria pharmaceutical trials. ( ABC News: Rebecca Trigger )

Mr Emerson said doctors told him he would have to take psychiatric medications, which have unpleasant side effects, for the rest of his life.

While things have improved, with an understanding employer and ongoing treatment, Mr Emerson now wants answers from the Australian Defence Force (ADF).

He has no medical diagnosis that links his use of the anti-malarial drug to his symptoms, but is concerned that so many coincide with listed side effects.

"This could all be wrong," he said.

"I'm not a scientist, but when I've got a dozen symptoms and they all fit the side effects of this drug ... it would be pretty coincidental.

"When I started to read the various articles about mefloquine, and the effects of it, I was in horror.

"It was like checking off a list of all my symptoms.

"Things that I hadn't even connected were all in this list of side effects."

Mr Emerson said he had no history of psychiatric issues prior to taking mefloquine.

The ADF acknowledged last week to the ABC that some people experience "ongoing issues" related to the use of mefloquine.

It said those affected could seek compensation through the Department of Veterans' Affairs if the mefloquine was prescribed for service reasons.

But this does not go far enough for Mr Emerson, who wants the Army to stop prescribing the drug and rehabilitate those affected.

"Find the people that have taken the drug — not everyone's going to be affected by it — contact them, see if they've got any of the side effects," he said.

"If they have, find a way to rehabilitate or fix the issues.

"I wouldn't wish anyone to go through my life for the past 10 years. Or even my life for a year. It's not a lot of fun."

ADF rejects involvement in unethical trials

In a statement, the ADF strongly rejected any suggestion that it would be involved in any research or practices that were either unlawful or unethical.

"While we acknowledge that a small number of people do continue to experience on-going issues, the Defence Pharmacy and Therapeutics Committee has not received any reports of permanent or lasting side effects attributed to mefloquine," the statement said.

"This is not unexpected as less than 2,000 ADF members have received mefloquine since 2000 and permanent side effects are rare," the statement, attributed to an unnamed spokesperson, said.

The statement said mefloquine was licensed by the Therapeutic Goods Administration (TGA), which was the appropriate body to assess its safety.

"Defence health policy incorporates all TGA recommendations and builds on that advice to ensure our medical protocols remain consistent with best practice," the statement said.

"Further to this (and unlike most civilians prescribed mefloquine) ADF members are provided access to medical support whilst deployed, have a medical examination on return from deployment and a further examination three to six months after return targeting any deployment related conditions.

"Such measures are a requirement of Defence's own policy, and go beyond what is recommended by the TGA and all other drug regulatory authorities around the world."

The agency did not say whether it had contacted people involved in the anti-malaria drug trials.

"Anyone who is concerned they might be suffering side effects from the use of mefloquine should contact a medical practitioner so they may receive a proper diagnosis and treatment," the statement said.