A NHS Lanarkshire spokeswoman said: "Anyone who has taken ecstasy - particularly the one described as 'Mortal Kombat', and who is feeling unwell, or who knows someone who has taken this type of drug in the past few hours, should attend or contact their local hospital for treatment and advice."
Police say that there are "deeply concerned" about Mikaeel Kular but stressed that it remains a missing person inquiry. Mikaeel has not been seen for 40 hours since he was put to bed on Wednesday night.
Police said they have checked CCTV from the local area but that nothing significant has been found so far and are following many lines of inquiry.
More than 150 calls have been made to the hotline for those with information.
The number is 0300 200 0200.
You can also contact Crimestoppers anonymously on 0800 555 111.
Police in Edinburgh have hailed the "fantastic" response from the public and urged anyone with information about Mikaeel Kular to contact them.
Supt McAinsh advised locals who want to join the search for three-year-old to dress warmly:
"We recognise that the local community is eager to help and we really appreciate their support. Those who are keen to become involved in the search should attend the North Neighbourhood Centre in West Pilton Gardens at 10am where they will be briefed by my colleagues.
"It is a cold January day, so please wear warm clothing and sturdy boots or footwear."
Enquiries are ongoing into the full circumstances surrounding this incident and any motorists who were on the road at the time and can assist Road Policing Officers with their investigation is asked to come forward immediately.
During the ongoing severeweather, motorists, particularly those driving high-sided vehicles, are advisednot to travel and delay any journeys until conditions improve.
Following a comprehensive review of all material submitted, Police Scotland has concluded there are insufficient grounds to support a criminal investigation at this time.
However, should further information come to light this will be looked into.
Reports suggest Unite, the biggest trade union, [attempted to influence the Falkirk Labour party with its members to ensure that its preferred candidate was chosen to fight the election]((http://www.itv.com/news/story/2013-07-04/tom-watson-quits-election-role).