Research published today by Asthma UK Scotland found pensioners were expected to put up with symptoms such as coughing and wheezing, and were sometimes left to find remedies themselves.
The report suggests that both older people and healthcare professionals may have "low expectations of asthma services" for this age group.
Asthma is often associated with childhood, but adults can develop the condition and there are around 54,000 asthma sufferers in Scotland over the age of 65.
The charity investigated the care these patients received from the NHS after a leaflet it produced on managing the condition proved popular in care homes.
Policy officer Elaine Carnegie said: "This research shows a far higher proportion of people with asthma develop the condition in adulthood than is commonly believed, and healthcare professionals can find it more difficult to diagnose in later life."
Asthma UK's report, The Forgotten Generation, is the result of a year-long project working with 30 patients in the Lothians area. It said: "Younger people are getting a better health deal than older people - the rationale seems to be that older people are on their way out."
One patient, identified as Marjory, who was diagnosed in her 40s but is now 65, said she had noticed she was no longer invited for an annual review of her symptoms. She said: "I don't think people are particularly interested in elderly people that have asthma - I think if it'd been somebody younger, they would maybe do a bit more about it, but I think it's just part and parcel of being old, really."
Another 66-year-old female, who had been diagnosed at 49, said: "As you get older you don't expect them to treat you the same way as when you are younger - you don't expect to come away with any good remedy for anything."
Ms Carnegie said: "Older people with asthma need to have their awareness and expectations of good asthma care raised so that they can then challenge perceptions and demand equal treatment."
More than half the patients interviewed had gone to A&E or been admitted to hospital as an emergency because of their asthma. One 62-year-old was told by a nurse at an asthma clinic she did not have asthma, only to suffer an acute attack and have to be rushed into a ward.
A spokesman for Age Scotland said: "Enabling more older people to enjoy a healthy life in their own home is essential if we are to meet the twin challenges of an ageing population and shrinking public finances.
"This report provides yet more evidence of where and how our health services can be adjusted to better meet the individual needs of older people."