A former head of the Army has admitted he would not take a controversial anti-malarial drug as he revealed his son had suffered severe depression while prescribed Lariam.Lord Dannatt said side effects of the drug could be “pretty catastrophic” and he apologised to troops who had taken it while he was Chief of the General Staff.He urged the Ministry of Defence to show “generosity” when reaching compensation settlements with hundreds of personnel alleged to have suffered mental health problems after being given the drug during deployments to malaria hotspots. Lord Dannatt also suggested the MoD was afraid of opening the “floodgates” to “very expensive” compensation claims if it admitted the drug had harmed troops.Philippa Tuckman, a military claims lawyer at Hilary Meredith, said thousands of personnel had been harmed.She said: “I hope we will hear that the MoD has finally accepted that Lariam should only be administered in very restricted cases, though it will have taken them far too long to get even to this point.“It is now time for the MoD to accept its past failings and to co-operate with the servicemen and women who have suffered and desperately need help and support to put their lives back together.”Ahmed Al-Nahhas, a lawyer representing veterans at Bolt Burdon Kemp, said: “Lord Dannatt’s apology is welcome and obviously stems from personal experience of the damaging effects of this drug on his immediate family.“Unfortunately, for many service personnel that apology will not be enough. Many continue to suffer with serious mental health conditions as a result of the MoD’s failures to safeguard their health.”An MoD spokeswoman said: “The vast majority of deployed personnel already receive alternatives to Lariam and, where it is used, it is only prescribed after an individual risk assessment.”But we have a duty to protect our personnel from malaria and, as the last defence committee report concluded, in some cases, Lariam will be the most effective way of doing that.”It continues to be recommended as safe by Public Health England and the World Health Organisation.”The drug’s manufacturers, Roche, told the BBC it “will continue to work with the Ministry of Defence to ensure that they have all the relevant information to ensure Lariam is prescribed appropriately”. MPs earlier this year criticised the Ministry of Defence for showing “lamentable weakness” in its duty to protect soldiers, sailors and airmen, by ignoring stringent precautions for handing it out.While Lariam is not the main anti-malarial drug used by the armed forces, at least 17,368 personnel were prescribed it at least once between the start of April 2007 and the end of March 2015, according to official MoD figures.Lord Dannatt, who was Chief of the General staff between 2006 and 2009, told the BBC’s Victoria Derbyshire programme his son’s experiences had put him off taking the drug. Because Bertie had that effect, whenever I’ve needed anti-malarial drugs, I’ve said, ‘I’ll take anything, but I’m not taking Lariam’,Lord Dannatt Lord Dannatt was head of the Army from 2006 to 2009Credit:David Moir/Reuters British personnel have regularly been given the drug to deploy to malaria regions such as Sierra LeoneCredit:Tugela Ridley/EPA Lawyers are representing hundreds of former personnel who claim they were wrongly given the drug because they were not given individual risk assessments or warned of side effects.Lord Dannatt said he was “quite content to say sorry” to those troops who had taken Lariam while he was head of the Army.The focus on operations in Iraq and Afghanistan, which were not malarial areas, meant that evaluating the drug had “slipped off the mainstream radar” and been put on the “backburner”, he suggested. Bertie Dannatt became ill after taking two doses of Lariam to visit Africa as a civilian in the late 1990s.Bertie was not in the Armed Forces at the time but had been prescribed the drug by his father’s Army doctor.Lord Dannatt said if his son had been left untreated “who knows where it would have gone”.He said: “He became extremely depressed, not the person that he would normally be, normally a very bubbly personable individual.“He got very withdrawn and we got very worried about him.”He went on: “Because Bertie had that effect, whenever I’ve needed anti-malarial drugs, I’ve said, ‘I’ll take anything, but I’m not taking Lariam’,” he said. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.