A UK-wide shortage of psychiatrists is forcing children with eating disorders and other troubled young people to wait longer for NHS care, it has been claimed.

About one in 10 consultant psychiatrist posts are unfilled and the rate of vacancies has doubled in the last six years, a major workforce survey by the Royal College of Psychiatrists found.

Services for those with eating disorders, under-18s with mental health issues and mothers struggling after the birth of a child are experiencing particular shortages, data collated by the college shows.

Prof Wendy Burn, the college’s president, said the findings were “very alarming” and raised doubts as to whether ambitious government plans to improve mental healthcare would be delivered.

The report warns that increasing gaps in the psychiatry workforce “come at a time of soaring demand for mental healthcare, with a shortage of psychiatrists contributing to the lengthy waits for treatment many patients face. The impact on patients’ lives can devastating, including divorce, debt and job losses.”

In England, 9.9% of full-time consultant posts in psychiatry are vacant, almost double the 5.2% which were unfilled in 2013, according to the college’s biennial workforce research report. In all 568 posts are vacant out of what should be a total workforce of 5,730 consultant psychiatrists.

However, Wales has the highest vacancy rate of the four home nations – 12.7% – while in Scotland 9.7% of posts are unfilled and in Northern Ireland it is 7.5%, giving a UK-wide rate of 9.6%.

Vacancies are widespread in England in key areas of the mental healthcare service, which the government and the NHS long-term plan have pledged to improve as part of a drive to reduce waiting times, increase the numbers who get help and give mental health “parity of esteem” with physical healthcare.

For example, one in six consultant posts in eating disorders services are empty. It has the highest rate of unfilled posts among the 13 specialist areas of psychiatry – 15.6%. The shortage is most pronounced in the east of England, where one in three posts have no doctor. In both the south-west and the south-east of England, almost 17% of posts are vacant.

But about one in eight posts in perinatal mental healthcare for new mothers (13.1%) and in child and adolescent mental health services (CAMHS) (12.1%) are unfilled. For example, 25% perinatal psychiatric posts are vacant in the west Midlands and 21.4% in the south-west.

Vacancies for CAMHS consultants are running at 10% or more in every region of England apart from the east and south-west. They are worst in Trent (16.9%) and the west Midlands (16.7%).

There is also a significant shortage (11.8%) of liaison psychiatrists, especially in the north-west (19.4%) and London (19%). They work in A&E units to help people undergoing a mental health crisis who turn up seeking help.

Eating disorder and children’s mental health charities voiced concern at the findings and warned that the major shortages in those areas of care could have serious consequences.

“We know eating disorder services are struggling to fill vacancies, which is impacting the ability of those services to treat patients as quickly as possible”, said Tom Quinn, director of external affairs at Beat Eating Disorders.

“This in turn has a detrimental effect on those patients, as early treatment is key to a full and sustained recovery.”

Support for patients with anorexia nervosa, bulimia nervosa and other eating disorders is a key part of NHS mental healthcare because of the high rate of death, including by suicide, linked to them. Sufferers are twice as likely to die as the general population, while those with anorexia – mainly girls and young women – are almost six times as likely to die, the highest risk for any mental disorder. However, some people wait at least 41 weeks to start their treatment as a result of what the royal college says is a “postcode lottery” in the availability of care linked to psychiatrist numbers.

CAMHS care is also important because of rising rates of self-harm and suicide in young people. Tom Madders, the campaigns director at YoungMinds, said:”We know from calls to our parents helpline that young people too often have to wait months to access support. With more and more young people looking for help, it’s crucial that action is taken to recruit and retain professionals specialising in children and young people’s mental health.

“But we need to do more than this. There has been welcome investment in the NHS, but services will remain overstretched unless more young people get help early on, before their problems escalate. That’s why we need a new government strategy that focuses on tackling the factors that lead to poor mental health and improving early support.”

The college wants ministers and NHS chiefs to improve working conditions for psychiatrists by, for example, having hot food available on nightshifts. And it wants the government to increase the supply of homegrown doctors by doubling the number of places in medical schools to 15,000.

The Department of Health and Social Care said it recognised the problem the college had identified.

“Expanding the mental health workforce is a key priority. We know more work is needed to meet rising demand on services and to ensure patients are getting the best treatment”, a spokesperson said.

“Our interim NHS people plan set out immediate actions we will take to fill vacancies and secure the staff we need for the future, including addressing pensions tax concerns, increasing university clinical placements by over 5,000 more and bolstering the workforce through greater international recruitment.”