CHAPTER 2-85: IPECAC SYRUP

INTRODUCTION

Ipecac syrup is an alkaloid derivative of the ipecacuanha plant (Cephaline ipecacuanha). The principal alkaloids, emetine and cephaline, both have emetogenic properties. The emetine extract has been used for the treatment of amebiasis. Syrup of ipecac is no longer widely available over the counter, nor is it recommended for home use by pediatricians.

MECHANISM OF TOXICITY

1. Mechanism of action. Ipecac causes vomiting in two ways: by direct irritation of the gastric mucosa, and by systemic absorption and stimulation of the central chemoreceptor trigger zone.

2. Acute ingestion can cause profuse vomiting and diarrhea, especially ingestion of the more concentrated fluid extract (no longer available in the United States).

3. The effects of overdose during pregnancy are not well studied.

4. With chronic repeated dosing, the emetine component of ipecac causes inhibition of protein synthesis, which is particularly demonstrated in cardiac and skeletal muscle cells. Another proposed mechanism for cellular toxicity is blockade of sodium and calcium channels.

5. Pharmacokinetics. Ipecac syrup causes emesis within 15–30 minutes of ingestion, and symptoms may last up to 1 hour in some cases. Ipecac is absorbed systemically; however, the rate and extent of absorption varies considerably among individuals. Emetine may be detectable in the urine for up to several weeks after chronic use.

TOXIC DOSE

Toxicity depends on the formulation and whether the exposure is acute or chronic.

1. Acute ingestion of 60–120 mL of syrup of ipecac is not likely to cause serious poisoning. However, the fluid extract, which is approximately 14 times more potent than syrup of ipecac, has caused death after ingestion of as little as 10 mL.

2. Chronic dosing results in cumulative toxicity because of the slow elimination of emetine. Repeated ingestion over time, as in cases of Munchausen by proxy or eating disorders, has been reported to cause myotoxicity with total accumulated doses of 600–1, 250 mg. Daily ingestion of 90–120 mL of syrup of ipecac for 3 months caused death from cardiomyopathy.

CLINICAL PRESENTATION

1. Acute ingestion of ipecac causes nausea and vomiting. In patients with depressed airway-protective reflexes, pulmonary aspiration of gastric contents may occur. Prolonged or forceful vomiting may cause gastritis, gastric rupture, pneumomediastinum, retropneumoperitoneum, or Mallory–Weiss tears of the cardioesophageal junction. One fatal case of intracerebral hemorrhage was reported in an elderly patient after a single therapeutic dose of ipecac syrup.

2. Chronic intoxication. In patients with chronic misuse, dehydration and electrolyte abnormalities (eg, hypokalemia) occur as a result of frequent vomiting and diarrhea, and myopathy or cardiomyopathy may develop. Symptoms of myopathy include muscle weakness and tenderness, hyporeflexia, and elevated serum CPK. Cardiomyopathy, with congestive heart failure and arrhythmias, may be fatal.

   1. "Munchausen by proxy." Children intentionally poisoned with ipecac typically have a history of recurrent hospitalizations for vomiting that seems refractory to outpatient medical treatment. The symptoms usually decrease in the ...