Final answer:
Syrup of ipecac is no longer recommended to treat patients who have ingested a poisonous substance because it can prevent poisoning of liver cells and has potential for fatal overdose.
Step-by-step explanation:
Syrup of ipecac is no longer recommended to treat patients who have ingested a poisonous substance because it can prevent poisoning of liver cells. The liver is exposed to carbon-tetrachloride, chloroform, and other toxic chemicals which can cause damage if not treated properly. In addition, ipecac syrup inhibits the reuptake of neurotransmitters, including epinephrine and serotonin, which can lead to side effects and potentially fatal overdose.