Estrogen patches, aspirin and ibuprofen are among 53 medications and classes of medications that are potentially inappropriate for the elderly if not carefully prescribed, according to a newly revised list by the American Geriatrics Society.

The list of potentially dangerous medications for adults 65 and older was posted online Friday by the organization.

Known as the Beers Criteria, the list is aimed at guiding doctors to avoid adverse drug events (ADE) for the elderly.

According to studies cited by the American Geriatrics Society (AGS), more than 40 percent of people 65 and older take five or more medications and more than a third of them will suffer an ADE each year.

"Older adults run a particularly high risk of ADEs, in part because age-related physiological changes and multiple health problems can make them more vulnerable to such reactions," Jennie Chin Hansen, the organization's CEO, said in a statement announcing the update to the Beers Criteria.

The Beers Criteria, created by the late geriatrician Mark Beers in 1991, was last revised in 2003 and is widely referenced by doctors in the field of geriatric care.

The 2012 list was updated by a panel of experts in geriatrics and pharmacotherapy based on the latest available research, the study says.

The Beers Criteria is broken down into three categories. The first features 34 classes of medications that have either a high risk of side effects among the elderly or may be ineffective on older adults. "Sliding scale insulin" is among the additions to the 2012 Beers Criteria in this group.

The second category includes 14 classes of medications that could potentially worsen certain diseases, risk factors or disorders for the elderly. Antipsychotics for dementia treatment are included in this group for increasing the risk of strokes.

The third category, new to the Beers Criteria, lists 14 medications that may be associated with more risks than benefits to older individuals. Aspirin for the purpose of preventing cardiac events for individuals 80 and older was placed in the new classification.

The panel dropped nineteen medications, including long-term use of the anti-depressant fluoxetine (popularly known as Prozac), from the 2003 Beers Criteria in the 2012 update.

The study notes that the Beers Criteria should only be used as a guide and that medications on the list may still be the best treatment for individuals in specific circumstances.

"[R]esponses to drugs vary significantly among older people," Todd Semla, co-chair of the panel that updated the Beers Criteria, said in a statement. "And, for some individuals, medications on these lists may be the best and only choice.

"The Beers Criteria alone should never dictate prescribing, nor should they be used punitively. They are intended to inform thoughtful prescribing decisions."

The American Geriatrics Society plans to update the list every three years.