This episode appears to be loosely based on the Claus von Bülow case. In 1982 von Bülow was arrested and convicted of the attempted murder of his wife, Martha Sunny von Bulow, an heiress worth $75 million in 1979. von Bülow was accused of injecting his wife with an overdose of insulin, which put her in a coma. He appealed and was then acquitted of the charge. Sunny von Bülow recovered from the first coma but then went into a second, irreversible coma in 1980 until her death in 2008. Claus von Bülow died in 2019 at the age of 92.
"A little jab will do ya." Lenny Briscoe says this after he learns the victim was poisoned by a needle injection. The phrase is a play on a commercial for a men's hair product, Brylcreem. The product was advertised heavily on TV in the 1950s and early 1960s. "Brylcreem... A little dab'll do ya." [10.21.2020]
The designer heroin that Carmichael referred to that contained the toxic substance methyl-phenyl-tetrahydro-pyridine (MPTP) was not intentionally cut with it. It actually happened as an accident: MPTP can be a byproduct of the chemical reaction used to convert meperidine (Demerol) into Desmethylprodine (MPPP). If the catalysts used in the reaction are not measured carefully and the chemicals are heated too long, MPPP winds up being converted to MPTP instead. Meperidine is a synthetic opioid analgesic that has been used since the 1930's, though it started to fall out of use in the late 1990's. Desmethylprodine is a more potent derivative of meperidine, and it is used as a cutting agent in certain high-end, designer brands of heroin. In 1976, a number of heroin users started presenting with symptoms of Parkinson's Disease. At first doctors were puzzled as to how this could be until the DEA discovered that recently seized shipments of heroin contained MPTP instead of the synthetic opioid MPPP. Chemists working for the DEA discovered a flaw in the method being used to convert meperidine to Desmethylprodine, a method which yielded MPTP instead. MPTP destroys the neurons that respond to the neurotransmitter dopamine in much the same manner as they are destroyed in people with Parkinson's, hence the symptoms of MPTP poisoning are almost identical to rapid onset Parkinson's.
At the same time this episode was made, a British general practitioner, Dr Harold Shipman, was found guilty of the murder of 15 of his elderly patients. He was sentenced to life imprisonment without parole. The police believed he was almost certainly responsible for up to 250 murders, making him the worst serial killer in British criminal history. He committed suicide in prison in 2004.
Brian Keane plays the part of Dr. Murphy in this episode. He previously played the part of McAlary in Episode 9.24, Refuge: Part 2 (1999).