The drug nitazene has been linked to overdoses
This week, The Irish Prison Service (IPS) issued an urgent drug alert to all prisons following HSE analysis confirming the presence of a nitazene type substance, associated with overdoses in Mountjoy.
In one case the substance is believed to have caused the death of a prisoner, with two other prisoners in a serious condition.
While the official cause will be determined by the Coroner, the IPS has launched an urgent information campaign which has led to a number of suspected nitazene tablets being surrendered.
The prison healthcare teams say they've adequate stocks of medicine should clinical intervention be required, with extra vigilance being taken.
It's understood the IPS is conducting a review of all medical presentations in Mountjoy Prison in recent days to establish if any other medical incidents are related to the drug.

Sharp Rise In M9 Collisions With Garda Call-Outs Up Year-On-Year
Councillor Seeks Clarity On How Often Nightclubs and Late Bars In Naas Are Inspected For Fire Risks
New Figures From CSO Reveal How Much International Protection Applicants Earn Compared To Average Worker In Ireland
Unpaid Eight-Month Work And Training Placement For Adults With Disabilities Branded "Extremely Unfair"
Department Of Education Defends Kildare SNA Cuts Amid Claims Of Reduced Need At Some Schools
Naas Nurses Threaten Escalation As Staffing Row Deepens
Driving Tests Face Disruption As RSA Testers To Strike Next Week
Jury Delivers Not Guilty By Reason Of Insanity Verdict In Ballyfin Demesne Strangling Case