A mental health patient died from a drug overdose after he was discharged by a mental health service due to missing an appointment, according to the health ombudsman.
The case is just one in a new report by the Parliamentary and Health Service Ombudsman (PHSO) which documents a series of "serious failings" in mental health services in England.
Another case highlighted in the report is that of "Ms G" who was left in seclusion after suffering an acute mental health crisis with no access to sanitary products.
The PHSO said the woman was forced to collect menstrual blood in a plastic cup.
Meanwhile, the PHSO highlighted how David West, a 28-year-old from Southampton, with a complex history of mental health problems, including bipolar disorder, was discharged from a community treatment team having missed an appointment.
He died shortly afterwards from a drug overdose.
The PHSO concluded that opportunities were "missed" to treat his illness and limit his deterioration.
Another case included in the report details how a vulnerable young man with biopolar disorder and autism was physically assaulted by another patient in a residential home.
The PHSO said the incident could have been avoided had a risk assessment been carried out by staff, some of whom were found to have worked double shifts.
It also highlights the case of a woman, 'Ms J', who died after having a fatal reaction to antipsychotic drugs.
The PHSO said that had doctors identified the condition, it is likely that Ms J would have received the appropriate treatment and survived.
PHSO Rob Behrens (pictured) said the cases "starkly illustrate the human cost of service failures".
He added: "These cases are not isolated examples. They are symptomatic of persistent problems we see time and again in our complaints casework."
The report states that workforce shortages in the NHS mental health service are "jeopardising" patient care and safety.
The PHSO warned that plans to transform mental health care might not be realised without action to address staff shortages in services.
Almost one in 10 posts in specialist mental health services in England are vacant.
The report states: "Patient care and safety is jeopardised by these workforce challenges.
"They show clinical staff ill-equipped with the skills to manage potentially violent situations, being expected to work double shifts leading to exhaustion, and clinicians having to treat conditions they have no experience of."
Mr Behrens added: "This report shows the harrowing impact that failings in mental healthcare can have on patients and their families.
"Too many patients are not being treated with the dignity and respect they deserve and this is further compounded by poor complaint handling."
Brian Dow, director of external affairs at the charity Rethink Mental Illness, added: "These findings underline the desperate need for reform and the sometimes devastating consequences of a struggling system.
"We do now have a blueprint for change but this will need drive and funding to achieve its aims, or we will continue to hear stories like these."
Nick Broughton, the chief executive of Southern Health NHS Foundation Trust - which was responsible for the care of Mr West - said: "I am extremely sorry for the mistakes that led to the death of David West after his involvement with Southern Health, and I fully accept our failure to look after him better.
"We have worked very closely with Richard West in reviewing the circumstances that led up to his son's tragic death, identifying areas for improvement and developing changes, and his support has been invaluable.
"We believe that working with patients, families and carers who have experience of the services we provide is the only way to ensure we can truly meet the needs of the people we care for.
"We welcome the publication of this report and the additional scrutiny on mental health services nationally. We have made a number of significant improvements in Southern Health, but we are clear that there is still much to do, both locally and across the whole country."
An NHS spokesman added: "This important report starkly and rightly recognises the scale of the challenge facing mental health services.
"It should be read and acted on by every part of the mental health service as over the next few years services expand, including for eating disorders, crisis care and psychosis. This will mean increased access, closer to home, to earlier and more effective treatment for greater numbers of people than ever before."
Copyright (c) Press Association Ltd. 2018, All Rights Reserved. Picture (c) Parliamentary and Health Service Ombudsman.