Nonetheless, the psychiatrist prescribed an antidepressant, escitalopram, one of a group of widely prescribed drugs called SSRIs (selective serotonin re-uptake inhibitors), which effectively boost levels of serotonin, a chemical messenger that carries signals between nerve cells in the brain.
Hours after taking the first dose, Katinka felt restless and agitated, as if she needed to be in constant motion. She didn't sleep that night and, by the following day, wasn't making any sense.
'I had this overwhelming feeling of doom,' she says. 'I thought I was living inside a video game - at one point I was 100 per cent certain I'd killed the children - and I'd been filmed killing them for national TV. I thought the police were outside waiting for me.'
In fact, Katinka had taken a kitchen knife and lacerated the whole of her left arm. 'I was in hell,' she says. 'It was terrifying.'