Here's a study on Suboxone/ Subutex overdoses in children:
Toxicity of Buprenorphine Overdose in ChildrenHayes BD, et al
Pediatrics2008;121(4):e782
This is one of the few reports of consequential overdose of buprenorphine in children. The retrospective review covers three years of data collected from poison centers for children under 6 with a history of BPN ingestion. There were 86 children who met the criteria, with a mean age of 2. The vast majority of ingestions occurred at the child's home, and all ingestions were considered unintentional and acute. The most commonly ingested was sublingual Suboxone, (BPN:naloxone in 4:1 ratio), either 2 mg or 8 mg, with a small number of Subutex (BPN only, no naloxone) tablets.
Interestingly, 26 percent of the patients were managed at home by the poison center without complications. More than a third of the patients remained asymptomatic, 50 percent had minor effects, and seven percent (six) patients had severe effects. Only those with follow-up were included in the analysis. There were no fatalities.
The most common clinical effects were those suspected from an opioid: drowsiness, lethargy, vomiting, and miosis. Respiratory depression was seen in six children, and coma occurred in two. It required about an hour for symptoms to become obvious in those who developed them, but symptoms were delayed up to three hours in a few cases. Although the study suffers from reporting bias, relied on historical recall, and lacked laboratory confirmation, the mean dose of BPN ingested was reported as 3 mg. Tablets are available in 2 mg and 8 mg strength. Sublingual Subutex is a white tablet; Suboxone is an orange tablet. One child was reported to have ingested 24 mg, and those ingesting the higher doses tended to have more significant symptoms. A 4 mg dose was apparently benign in all cases. In this retrospective analysis, a 4 mg ingestion appeared to be the cutoff for concern or need for a mandatory EP evaluation (gutsy move, if you ask me).
Minimal gastric decontamination was initiated. One patient did require intubation and mechanical ventilation. About one-quarter of the patients received naloxone, and the vast majority had some response. Dosing parameters were vague because the dose or indication for naloxone was not recorded in all cases. It has been reported that large doses of naloxone, sometimes 10 times the standard dose, is required to reverse BPN respiratory depression.
The authors note that BPN overdose is essentially an opioid overdose, and it produces CNS and respiratory depression, miosis, and occasional vomiting. Prior reports have demonstrated that accidental oral BPN overdose, even in children, is usually quite benign. Serious toxicity is not to be expected, and was not seen if less than 4 mg were ingested. Because the drug can be dispensed in an 8 mg tablet, the potential for toxicity in a small child is obvious. Although the most common product ingested was the buprenorphine-naloxone combination, the naloxone has no protective anti-opioid effect when taken orally. Only one child required mechanical ventilation, and two were treated with naloxone infusions; the exact reasons for these interventions were unclear.
These authors highlight the usual benign course of an accidental pediatric BPN ingestion, and believe that those merely exposed to a taste of the tablet, even the 8 mg dose, can be safely observed at home. This assumes, of course, reliable parents and a perfect history. Because BPN is usually administered sublingually, swallowing the pill is expected to decrease bioavailability.The duration of clinical effects was between two and eight hours in most patients. The drug does have a long serum half-life, so prolonged observation may be required if significant symptoms are present within the first few hours or if they persist. The potential for delayed onset of CNS and respiratory depression is highlighted, although symptoms will likely develop within two to three hours postingestion if a significant exposure has occurred. The authors suggest a minimum of six hours observation for children exposed to BPN orally, with discharge from the hospital being appropriate if there are no clinical concerns at the six-hour mark.It was the authors' experience that naloxone successfully reversed BPN. It has been stated that exceptionally large doses are required, but that was not confirmed in this study. Due to a paucity of reporting data, accurate naloxone dosing regimens cannot be forthcoming. It was emphasized, however, that the duration of action of naloxone is significantly less than that of BPN. If naloxone is used as a reversal agent, the authors suggest continued observation (not quantified) and perhaps even a continual IV infusion.
Given the increased use of BPN for opioid addiction, the potential for accidental childhood exposure will likely increase. Parents take this drug home, and the orange pill is inviting to a toddler. Interestingly, a veterinary product in an injectable form is available for pain relief in pets, and was involved in some of the exposures in this report. Although limited by retrospective data, the authors conclude that unintentional BPN ingestion is generally well tolerated in children, with respiratory depression being unusual. They suggest that an exposure documented to be greater than 2 mg in a child under 2 should be referred to the ED for evaluation. Others can be observed at home with a reliable (I say, pristine) support system, including reliable parents, transportation, and ability to closely observe. Those suspected of significant BPN exposure should be monitored in the ED for six hours, at which time asymptomatic patients can be safely discharged.
Comment: This article confirms prior reports that accidental oral BPN exposure is relatively safe when compared with the serious consequences of morphine or methadone ingestion in children. While BPN has narcotic effects, this drug only partially stimulates the mu receptors, resulting in clinical effects similar but significantly less than morphine or methadone. One would expect the child or adult overdosing on this product to have a classic narcotic toxidrome (miosis, sedation, respiratory depression, decreased bowel sounds, urinary retention, and perhaps bradycardia and hypotension). The delayed onset of BPN clinical activity is highlighted, but the overall safety of the standard 2 mg tablet, even in a small child, is reinforced.
So they are saying 4mg orally in kids is pretty much always benign, and up to 8mg could be treated with home care. Oral administration is of course about half as potent as sublingual, but I imagine these kids chewed the pills instead of swallowing whole, which surely delivered a decent amount of the drug through the mouth.