People with dementia and their carers have marched on Parliament to lobby MPs to end means-testing for personal care.
They say patients with other conditions are given such care for free.
The 500-strong march, organised by the Alzheimer's Society, also renewed calls for key drugs to remain available on the NHS.
The National Institute for Clinical Excellence is currently consulting on whether the drugs should be withdrawn from NHS use.
The march was originally organised to highlight the situation of people with dementia who have to pay for help with washing, eating and going to the toilet.
Clive Evers, director of information and education for the society, said: "These are services which are means-tested. But there are other conditions, such as cancer, where we understand these charges do not apply, and the services are seen as health care needs.
"This is the issue. We believe there is discrimination against people with dementia."
Neil Hunt, chief executive of the Alzheimer's Society, said: "The voices of people affected by dementia must be heard in the general-election debate.
"We are calling on all candidates and political parties standing at the election to look seriously at what can be done to make life better for people with dementia and their carers across the UK.
"The ballot box may be the only way we will ever get much-needed change and an end to the discrimination people with dementia and their carers face on a daily basis."
People in Scotland receive free personal care. But the Department of Health say introducing the same system in England would cost around £1.5 billion and would only benefit the better off.
It said seven out of 10 residents in care homes had some or all of their personal care paid for, but personal care in the home was paid for either by the recipient or the local council, depending on the person's financial status.
A Department of Health spokesman said: "Access to continuing care is determined on a case-by-case basis.
"Dementia is often raised as a specific example but we cannot make care free on the basis of diagnosis, but on the basis of need."
Gordon Lishman, director general of Age Concern England, said: "It is appalling that older people and their families continue to be the victims of a shambolic care-funding system.
"The government must make it a priority to create a clear, fair system that puts an end to this national disgrace."
One in 20 people aged over 65 and one in five over the age of 80 have a form of dementia.
People on the march will also renew calls for four Alzheimer's drugs - Aricept, Exelon, Reminyl and Ebixa, the only medications licensed in Britain for the treatment of the disease - not to be withdrawn.
The National Institute for Clinical Excellence, in its draft guidance, said the drugs were not cost-effective.
This week health minister Stephen Ladyman said NICE should take social, as well as financial, implications into consideration.
But NICE chief executive Andrew Dillon said: "We would like to make it clear that, contrary to recent press reports, it has not been asked or told by ministers to reverse its advisory committee's provisional recommendations on the use of these drugs.
"Final guidance is expected in October 2005."
Mr Evers said: "We are shocked and saddened that people with Alzheimer's might be denied the only three treatments that are available to them.
"We hope the march will provide a much higher profile for the issues we want the government to address."