Antidepressants and oral glucose agents are now common poisons: relatively benign.
Emergency department physicians see many fewer cases of children who have ingested cleansers or drain solutions than they once did, which is probably an indication that the repeated messages about keeping these substances out of reach has gotten through to the public, said Dr. Johnson, director of pediatric emergency medicine at Mission Hospital in Mission Viejo, Calif.
Instead, medical drugs and rave drugs have taken their place.
Fortunately, most of the new toxins being seen are much less likely to be fatal than those of the past, Dr. Johnson said.
The new-generation antidepressant drugs are a case in point, he said. They have become hugely popular, so they are available and do fall into children's hands. But part of the reason they are so popular is because they are so well tolerated, and because their side-effect profile is good, they tend to be relatively nontoxic.
Dr. Johnson talked about the new toxins that physicians see in the emergency department:
* One-pill killers. Although many drugs have become less toxic, some drugs that children, especially younger ones, may ingest accidentally can be life threatening. These drugs include propranolol (one or two 160-mg tablets), verapamil (one or two 240-mg tablets), chloroquine (500-mg tablet), clonidine (0.3-mg tablet), Lomotil (2.5-mg tablet), glyburide (5 mg), and theophylline (500-mg tablet).
These drugs tend to belong to grandparents, Dr. Johnson noted. Fortunately, theophylline is "falling off the radar" as it is less frequently prescribed for asthma.
Some of the other substances that can kill with a small amount and are still seen include camphor (1 teaspoon of oil in a 2-year-old, or 2 teaspoons of Campho-phenique, or 5 teaspoons of Vicks VapoRub), lindane (2 teaspoons of 1% lotion), and benzocaine (half teaspoon of baby Orajel).
* Oral sulfonylureas. Oral sulfonylureas have become so popular that they account for more than 50% of all child ingestions of drugs, and they have a l0w toxicity threshold. Symptoms are going to include central nervous system depression, perhaps focal neurologic signs, and those indicative of a severe hypoglycemic state. Peak plasma levels are sometimes not reached for 8 hours. Treatment is charcoal, glucose infusions, and, sometimes, diazoxide. "A very small dose can get you into trouble," he said. "'These kids require admission to the hospital."
* Clonidine. The rate of clonidine poisonings increased 2.5 times during the 1990s, and the medication sometimes belongs to another family member, but, as often, it is the child's own. "Death can occur, but there are really minimal toxic effects," he said. "Often there are not a lot of signs at all--a little lethargy.'"
* Serotonin reuptake inhibitors. The explosion in the prescribing of these drugs means that they are readily available for overdose. With fluoxetine, sertraline, and paroxetine, it is possible for an overdose to produce serotonin syndrome, with symptoms such as agitation, myoclonus, and hyperthermia. However, Dr. Johnson said he has never seen the syndrome in an overdosed patient. Instead, the common scenario is that a teenager who is prescribed the medication does not take a massive overdose, but rather just enough to feel a little different, and a friend or relative notices the person is lethargic and brings them to medical attention.
Treatment is often simply supportive care, while sedation and cooling are used for serotonin syndrome. "It is almost impossible to get into serious trouble with these drugs because of their high safety profile," Dr. Johnson said.
* Anticonvulsants. Emergency departments are seeing an increase in cases of children experiencing toxicity from seizure medication they are taking. Dilantin is not frequently used for seizures, and that is a good thing, Dr. Johnson said. The symptoms of toxicity seen with carbamazepine and gabapentin--the drugs that have replaced it--are more benign, although also more subtle.
In one review of 14 cases of carbamazepine overdose toxicity in children less than 5 years of age, the common clinical findings were nystagmus, drowsiness, and tachycardia. In a review of 20 cases of gabapentin overdose, the clinical characteristics reported were dizziness, nausea, tachycardia, hypotension, and ataxia.
* Rave drugs. Overdose with rave drugs continues to be seen in younger and younger patients, Dr. Johnson said.
The first of these drugs to be reported in the medical literature was ecstasy in 1980. Now, gamma-hydroxybutyrate (GHB) and ketamine are probably the most frequently used.
GHB is "impressive to see in action," Dr. Johnson said. The drug takes effect fast--it can produce profound coma in 30 minutes--and wears off fast--in 4-6 hours.
Treatment is often supportive because it does wear off so quickly, but it can cause vomiting so there is the potential for aspiration and choking, he said. Ten percent of patients seen in an emergency department will need intubation.
In the past few years, a number of GHB precursors have become available. These appear to be readily converted to GHB, so they tend to have similar effects, but not much is known about them, he said. There are even Internet sites that provide simple recipes.
Ketamine generally produces only mild intoxication, and that is why adolescents choose to use it. However, there is a range of effects, and some individuals can have hallucinations, delirium, and amnesia. Care is supportive, but some individuals will have temporary emergence agitation or even psychosis. Verbal memory deficits have been demonstrated in human users.
* Antihistamines. Adolescents have begun to abuse antihistamines, a practice they refer to as "robo-ing." He said, "It is kind of a big deal in my area."
Different agents have variable effects, although, in general, toxicity often occurs with three to five times the usual daily dose. At 20-40 mg/kg, diphenhydramine overdose can be fatal. However, most adolescents seem to be sophisticated about knowing how much of a particular agent to take for the desired effect, and so Dr. Johnson said he has almost never seen cases in which individuals got into truly serious trouble. Urine screens can detect most common antihistamines.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Children's Health|
|Author:||Kirn, Timothy F.|
|Publication:||Family Practice News|
|Date:||Mar 15, 2004|
|Previous Article:||Ingestion of a foreign body is quite likely in retarded children: despite swallowing difficulties.|
|Next Article:||Watch out for dental caries during checkups; fluoride is child's best ally.|