A D.C. woman charged with felony murder for feeding her month-old son a fatal dose of a prescription allergy and motion sickness medication initially lied about giving the drug to the boy, then told a police detective she did not believe it would harm him, according to an affidavit released Monday.

Tisheena Louise Brown, 31, told the detective her son, Hakeem Brown, was not keeping food down and was being “fussy,” so she ground up a tablet of Phenergan and put a small amount on his tongue, according to the affidavit, signed by Detective Jed D. Worrell. She did so even though she had been warned the drug — which carries the generic name promethazine — should not be given to children younger than 2, according to the affidavit.

This month, the medical examiner ruled the death a homicide caused by promethazine intoxication, and D.C. police said Sunday they had arrested Brown on charges of felony murder and first-degree cruelty to children. She appeared Monday in D.C. Superior Court and was ordered held until another court appearance later in the week, authorities said.

The unusual case is a tragic chapter in a difficult life. According to Worrell’s affidavit, Brown has an “admitted history” of abusing prescription drugs and sometimes tries to use fake IDs to get drugs from hospitals. Hakeem suffered withdrawal from drugs she had taken during her pregnancy, the affidavit said.

She had Phenergan prescriptions for herself, the affidavit said. The drug is used to treat allergies, motion sickness and nausea.

After Brown’s son was rushed to the hospital from the 2900 block of Akron Place SE early on Sept. 18, Brown told a detective she had given the boy only an over-the-counter gas relief medication, according to the affidavit. She said she fed him about 10 p.m. the night before, put him to bed about 10:30 p.m. and noticed sometime after 2 a.m. that he was “blue and wasn’t breathing,” the affidavit said.

The medical examiner found promethazine in the boy’s system, and Brown then admitted giving her son the drug, according to the affidavit. She told the detective she did not believe doing so would be harmful because he had already received morphine to treat his withdrawal.

A man who identified himself as Tisheena Brown’s uncle but declined to provide his name said Monday that his niece was “a real nice person, and whatever happened, I think it was a freak mistake.” He said that Brown had suffered complications during her pregnancy and that both she and her son were under a doctor’s care. He declined to name the doctor or say whether the doctor had prescribed Brown or her son any medications.

“She loved her kid, and wherever she go, she took the baby with her,” the uncle said. “She would never do something intentionally to hurt him.”

He declined to answer other questions about the case. Spokesmen for the D.C. police department and the Office of the Chief Medical Examiner also declined to provide additional details.

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