The funding of mental health care for Scotland's prisoners must be increased after the number of self-harm incidents "skyrocketed", an MSP has said.
Figures show there were 762 incidents in 2018, compared with 532 in the previous year - a jump of 43%.
These include burns, cuts, attempted suicide, ligature, overdoses and swallowing items.
The Scottish government said it was increasing the support for prisoners with mental health needs.
The highest number of incidents was at HMP & YOI Grampian in the north east which recorded 175 cases in 2018 of which 138 were categorised as "cuts".
Of the 762 total incidents recorded across Scotland, 517 were for cuts, 72 were categorised under "swallows item", 41 for "overdose" and 31 as "attempted suicide".
The figures were published following a Freedom of Information request made by the Scottish Liberal Democrats.
The party's justice spokesman, Liam McArthur MSP, said: "Incident numbers have been on an upward trajectory for years but last year they skyrocketed.
"The scale of self-harm in Scotland's prisons is devastating. This must prompt serious new investment in prison mental health care.
"Prison staff are working incredibly hard but they don't have the resources or staff they need."
He added: "It has been two years since the Scottish government accepted Scottish Liberal Democrat proposals to expand the mental health workforce in prisons.
"However, so far there are just two new staff across Scotland's 15 prisons. Ministers still can't tell us how many extra staff there will be in the end.
"Staff, prisoners and the communities they return to have every right to demand better. We need more mental health professionals deployed in our prisons now. This will help save lives."
A Scottish government spokesman said: "We recognise that people entering the criminal justice system often have complex needs.
"This is why in recent years SPS (Scottish Prisons Service) have improved reporting procedures and awareness of the risks of self-harm among prison staff, ensuring that cases are properly recorded and appropriate care and support are provided.
"SPS are working closely with NHS staff, responsible for mental healthcare provision in Scotland's prisons. In addition, HMIPS is currently carrying out a review of mental health services at HMP YOI Polmont and a review of forensic services, which will include provision in the prison estate, was announced last week.
"The learning and recommendations from these reviews will inform our approach in the future."
The spokesman added: "Through our 10 year mental health strategy, we are delivering an increase in support for the mental health needs of people detained in prison.
"The strategy aims to increase the overall mental health workforce by 800 additional staff, with prisons also benefiting from this enhanced workforce.
"This is supported by investment rising to £35m by 2021-22. The mental health staffing model in each prison is determined by each NHS board and any changes will be monitored jointly with the SPS."