An Adelaide mother has been jailed for spiking her children's chocolate milk with sleeping pills in what the judge described as an "extremely sad case".

Key points: The mother was jailed for three years with a non-parole period of 15 months

The mother was jailed for three years with a non-parole period of 15 months The children reported feeling "strange, abnormal and slow" after drinking the milk

The children reported feeling "strange, abnormal and slow" after drinking the milk Judge Chivell was told the mother had stopped taking antidepressants before the incident

District Court Judge Wayne Chivell sentenced the mother, who cannot be identified to protect her children, to three years' jail with a non-parole period of 15 months.

The 47-year-old woman pleaded guilty to five counts of aggravated committing an act likely to cause harm.

Judge Chivell said the mother crushed the pills and placed them in two litres of chocolate milk before handing each of her four children — aged 10 to 17 — a glass each in March 2018.

"Each one finished the chocolate milk," he said.

"They variously reported feeling funny and strange, abnormal and slow, suffering from head spins and feeling dehydrated.

"When some of them told you they were feeling abnormal, you offered them some Panadol, which they took."

Judge Chivell said two of the children fell asleep straight away, but the other two took a bit longer, before she attempted to take her own life.

"You contacted a friend of yours and told her what had happened. She contacted emergency services and later she came to the house," he said.

The mother felt immediate remorse

Judge Chivell said she woke up one of her sons and started apologising to him repeatedly.

"You told him what you had done. He woke up the other children. Each of them were taken to and later examined at the Women's and Children's Hospital," he said.

The court was told the dosage given to the children was "above the normal therapeutic level" but not so high that "extremely pronounced effects were produced".

"This is an extremely sad case, not only for you, but for your entire family," Judge Chivell said.

"It is clear that at the time of the offending, you had reached a crisis point as a result of your declining mental health.

"You had ceased taking antidepressant medication with the approval of your general practitioner in late 2017, about six months prior to the incident.

"You had been taking that medication for a period of about 20 years prior to that."

The children were seen at the Women's and Children's Hospital in Adelaide after drinking the milk. ( ABC News )

Judge Chivell said the mother's offending was "premeditated" because she told a psychiatrist that she planned to put her children to sleep and take her own life three days beforehand.

He said the offending was a "gross breach of trust".

"The nature of your relationship with the victims was such that they trusted you unreservedly," he said.

"They had every right to expect you to look after them."

Judge Chivell accepted that the mother was remorseful and posed a low risk of reoffending.

He backdated the sentence to the time she was taken into custody in March 2018, meaning she would be eligible for parole "within a fairly short period of time".