A baby was found to have heroin, crack cocaine, cannabis and psychoactive drugs in his system when he suffered a heart attack at a house in Leeds.
Doctors made the shocking discovery when they carried out tests after the seven-month-old baby was found in a collapsed state.
The baby fully recovered despite suffering a cardiac arrest caused by the ingestion of a series of illicit drugs.
Details of the incident were revealed as the baby's mother was sentenced at Leeds Crown Court after she pleaded guilty to an offence of child neglect.
Toxicology tests were carried out on the youngster after he was taken to hospital by ambulance in August 2017.
Christine Edgerton, prosecuting, said blood, urine and hair strand tests revealed the baby had heroin, crack cocaine, cocaine and cannabis in his system.
The baby also tested positive for fentanyl, carfentanyl - synthetic versions of heroin - and a "psychoactive substance" known as FIBF.
FIBF has been sold online as a party drug as it causes a sense of euphoria in users.
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It has the potential to be life-threatening as it can depress the respiratory system.
Ms Edgerton told the court: "It is not possible to say how the drugs ended up in his body."
The prosecutor said the baby may have ingested the drugs through contact with surfaces contaminated with illicit drugs.
It was also possible the drug could have ended up in the tot's system from being in contact with someone who had taken the drugs.
Police went to the mother's home in south Leeds after the results of the tests were known.
As they searched the property they noticed that carpets had recently been vacuumed.
Two vacuum cleaners were seized from the house.
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Their contents were examined and traces of cocaine were found inside.
The mother, aged in her 20s, admitted to police that she used cannabis and cocaine but denied being a user of heroin or crack cocaine.
She told officers she did not take illicit drugs in the presence of the child or store them where they could be reached by children.
Ms Edgerton also said the mother admitted that she let other drug users into her home and allowed them to use the property to take drugs.
She added: "The defendant accepts that she is responsible for the inadvertent exposure to (the baby)."
Kama Melly, QC, mitigating, said a lengthy and complex investigation had taken place in the two years since the incident as the defendant had initially been facing a more serious charge.
Miss Melly said the baby had been taken into care.
She added: "That has been the most significant life event that she has had."
Miss Melly said her client was now free of drugs had had been receiving treatment for depression.
The mother was given as nine-month prison sentence, suspended for 18 months, and ordered to take part in a 30-day rehabilitation activity requirement.
She sobbed in the court dock as she was sentenced by judge Penelope Belcher.
The judge told her: "You will now understand the dreadful impact that drugs can have.
"I make it absolutely plain that you did not administer those drugs.
"But you now understand (the baby) could have lost his life or been seriously damaged in some way.
"Using drugs in the presence of children is a serious matter."