The peak body for youth affairs, the Youth Coalition of the ACT, said the demand on youth mental health facilities would continue to increase, and waiting periods should sound a warning to the government for the need for more preventive and acute services.

As of November 8, there were 30 people waiting for a full assessment at the Northside Child and Adolescent Mental Health Service, 24 people waiting for a full assessment at the Southside service and 22 waiting for access to a specialised program in Woden treating eating disorders.

An ACT Heath spokeswoman said patients were assessed when they were first referred to the clinic, and those young people perceived to be at high risk are scheduled for a full assessment within 48 hours.

All other patients faced an average wait of six weeks to be offered a full assessment and begin treatment at the clinics.

ACT Health's website said clinicians at the Northside and Southside services assist in the management of serious and complex problems in children and adolescents aged under 18 through comprehensive assessment and treatment.

The Youth Coalition of the ACT director Emma Robertson said as the pressures faced by young people continued to increase and the stigma attached to seeking psychological help was removed, more people would seek out youth mental health services.

''The sorts of things young people are experiencing are very much related to things around body image, stress, particularly stress around school work,'' she said.

''The world's not getting kinder around those things, we're not easing up on the pressure.''

The ACT Health spokeswoman said that while the young people remained on the waiting lists, the clinician allocated to conduct their full assessment checked in with their patients periodically, to ensure that their level of risk was not escalating.

The spokeswoman said there are also avenues for emergency intervention if required, including access to the Crisis Assessment and Treatment team.

''People can also present to the emergency department at any stage for review and assessment, and admission will be arranged if medically indicated,'' she said.

Ms Robertson said she would like to see a greater investment in acute and early intervention and preventive mental health services for young people.

''Unfortunately, what I think happens far too often is that when we do get a small amount of money that's become available it gets put into the acute, tertiary end response because that's where there's the most crisis and it's more likely to have stories in the media, and we always scrimp on the preventative end,'' she said.