Doctors will not be able to compel people solely hooked on drink or drugs to undergo treatment under the terms of proposed mental health legislation.
New rules will introduce compulsory treatment
Health Minister Rosie Winterton announced the conditions for compulsory treatment laid out in the draft Mental Health Bill had been modified.
Critics still fear the plans could lead to people with only mild conditions being locked up and forcibly treated.
And mental health experts said many more changes were still needed.
Concerns were raised by a report by MPs and peers published in March.
The joint House of Commons and House of Lords Committee said the draft Bill made it too easy to force a person into compulsory treatment.
It feared treatment would be forced on those who might be a nuisance, but do not actually pose a real threat.
Current laws do not allow people with severe personality disorders who have committed no offence to be detained.
But the original 2002 draft bill proposed measures to detain mentally ill patients for their own protection and the protection of others, even if their condition was not treatable.
There were also proposals to allow compulsory treatment in the community under community treatment orders.
When it was published, an unprecedented 2,000 objections were made.
Last autumn, a revised draft was published which tightened the definition of who the laws could apply to.
The Bill says treatment can be enforced "for the protection of other persons".
But the committee said this should be changed to cover people who "pose a significant risk of serious harm".
It also said patients should never be treated under compulsion unless their decision making was impaired and the treatment was of therapeutic benefit.
Announcing the government response on Wednesday, Ms Winterton said ministers had accepted well over half the report's 107 recommendations.
This includes beefing up patients' rights to decide whether advocates can see their records, and to meet with advocates in private.
Consideration will also be given to the use of advanced statements from patients, detailing how they would like to be treated in the event of a deterioration in their condition.
Ms Winterton said: "Although the majority of mental health patients pose no danger to themselves or others, the government has a duty to protect people with serious mental health problems from harming themselves or other people.
"The Bill introduces a number of new safeguards for patients' rights and we are confident that the Bill's provisions will mean that compulsory treatment will be used only when essential.
"Compulsion will only be used as a last resort."
More work needed
Paul Farmer, chairman of the Mental Health Alliance, said a lot more work was needed before the draft legislation became workable.
He said: "Mental health workers, service users and carers will be pleased that the government has said it will consider improving patients' rights.
"But they will be disappointed and angry that the government intends to press ahead with plans to broaden out powers of compulsion and deny professionals the flexibility they need to offer people the right care and support."
Marjorie Wallace, of the mental health charity Sane, expressed concern that the proposals would not improve the lives of the majority of mentally ill people.
"While there are 400 vacancies and rising for consultant psychiatrists, a chronic shortage of mental health nurses and a lack of beds, such measures as compulsory treatment in the community could become a temptingly cheap alternative to in-patient or other skilled 24-hour care."
Angela Greatley, of the Sainsbury Centre for Mental Health, said: "There remains a long way to go before we have a Bill that all those who work in or use mental health services can support and implement."
Dr Tony Zigmond, of the Royal College of Psychiatrist, said: "It is sad that government still fails to understand that it is unethical to force treatment on people who are well enough to make their treatment decisions."