Irish soldiers are reportedly growing increasingly worried about the effects of a notorious anti-malaria medication the Irish Army still uses which has been banned in the US over safety concerns.

Lariam (mefloquine) has been linked to a wide variety of psychiatric side-effects including anxiety, depression and irritability.

Despite growing concerns though, the Irish Defence Forces maintain that it is the most effective anti-malaria agent currently available to treat troops with.

The drug, however,  has been found to induce side-effects in as many as 25 percent of users, including suicidal tendencies, anxiety, aggression, paranoia, nightmares, ringing in the ears, depression, panic attacks, hallucinations and psychotic behaviour.

The long term effects are even worse than the short-term ones, though. Thomas Moore, a former private in the forces, told Dublin’s Tribune that four years after taking the drug he’s still suffering adverse effects including severely reduced sleeping time (he averages between two to three hours’ a night), apathy and lack of energy.

The former soldier shockingly described how he barely had the energy to hammer a nail into a wall any more. He used to be running and training all the time.

He also described to the Tribune how the Defence Force doctors refused to admit that he was suffering from adverse side effects of the controversial medication.

Worryingly there is an increasing body of international research which points to the toxicity of the substance.

A well-known clinical trial on rats found that the medication was capable of inducing long-term central nervous system damage. The United Press International found in 2002 that Lariam users were five times more likely than non-users to report having mental problems that could lead to suicide.

Yet the Defence Forces remain undeterred. A statement from the army said:  "Every medicine has the potential to produce side-effects but contracting malaria can be fatal. In the case of Lariam, side-effects have been reported by a small number of troops prescribed the drug. However, the Defence Forces undertake a number of initiatives to identify, and where necessary, treat any potential side effects as early as possible."

The substance was discovered by the US military shortly after the Vietnam War in a drive to combat malaria. More modern alternatives are reported to have far fewer side effects.