Some prisoners with a disability feel they are "punished" simply for their condition, while others report they are bullied by fellow inmates.
The findings are among a number made in a new report published by the Irish Penal Reform Trust (IPRT) which argued that changes need to be made regarding how prisons assist inmates who have a disability.
Some 31 semi-structured interviews were conducted for the report, including with 16 prisoners with disabilities, as well as representative organisations of persons with disabilities, prison officers, civil servants and public officials.
The prisoners interviewed included people with physical and/or mobility impairments, some with mental health disabilities, acquired brain injuries, deaf people, and the visually impaired.
It found that isolation in cells, limited availability of accessibility aids, lack of appropriate information on prison services, and limited opportunities to communicate with peers and family members are just some of the barriers and human rights issues facing prisoners with disabilities in the prison system.
Among the general trends that emerged in the report is that prisoners with disabilities face significant difficulties navigating prison and prison services. "Some prisoners were effectively confined to their cells due to the inaccessibility of the prison environment, and had services brought to them," it said.
Others said they were denied specific accessibility aids, including a white cane used by the visually impaired, while access to sign language interpretation for deaf prisoners was extremely limited.
It also said there was limited understanding of disability rights and concern regarding the right to health for people with disabilities in prison.
"The issues raised included the removal of medication and management of medication upon entry to prison, during prison stay and in the transition out of prison," it said.
It found that informal peer support from other prisoners was likely to be the main form of support for people with disabilities in prison, but some participants reported instances where prisoners bullied disabled prisoners.
Concerns were also raised over the incentivised regime which operates within prisons.
"Some prisoners reported being punished for disability-related behaviour (often perceived as challenging behaviour, without exploring how the behaviour resulted from the inaccessibility of the prison environment) or losing out on the rewards for not taking part in programmes that were not accessible to them, including education programmes," it added.
The report makes a range of recommendations, including that accessible information on rights, regimes and complaint systems in prison is provided, access to single-cell accommodation, continuity and equivalence of care between community and prison, and banning solitary confinement.
IPRT Executive Director Fíona Ní Chinnéide said: "Even at the most basic level, people with disabilities in prison must have access to the entire physical prison environment on an equal basis with other prisoners."