Daniel, four, was starved and beaten for months before he died in March 2012 at his Coventry home. His mother and her partner were jailed for his murder.
Dr Mohammad Pathan did not provide a "safety net" when teachers raised concerns over Daniel's appearance and weight.
He was found guilty of misconduct last month but remains fit to practise.
The Medical Practitioners Tribunal Service said the warning, imposed on Wednesday, would last for five years.
The panel ruled: "On 25 January 2012 the deputy head teacher of Patient A [Daniel] telephoned you to raise concerns regarding Patient A's loss of weight, appearance and behaviour concerning food.
"Following receipt of the telephone call you failed to act adequately and attach sufficient weight to the information provided during the telephone call and you also failed to take adequate account of other information available to you, including Patient A not attending for some or all of follow-up treatment for a fractured humerus.
"By doing so you failed to put in place a 'safety net' to safeguard the interests of a child at risk."
Dr Pathan had denied he was aware of some concerns.
Daniel's mother Magdelena Luczak and her partner Mariusz Krezolek were jailed for a minimum of 30 years each in 2013.
A GP has been given a warning for not acting adequately over concerns raised about starved schoolboy Daniel Pelka.