What is the risk of toxicity from ingesting one over-the-counter (OTC) boric acid supplement orally?

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From the FDA Drug Label

Warnings For external use only ... If swallowed, get medical help or contact a Poison Control Center right away. The risk of toxicity from ingesting one over-the-counter (OTC) boric acid supplement orally is unknown but potentially severe.

  • Key points:
    • The label warns against ingestion
    • It advises to get medical help or contact a Poison Control Center right away if swallowed Given the warning for external use only and the advice to seek medical help if ingested, it is clear that ingestion poses a risk, but the exact level of toxicity is not specified in the label 1.

From the Research

Taking a single over-the-counter boric acid supplement orally poses significant toxicity risks and should be avoided. Boric acid supplements are intended for vaginal use only and should never be taken by mouth. Oral ingestion of boric acid can cause acute poisoning with symptoms including nausea, vomiting, diarrhea, skin rash, and in severe cases, kidney damage, seizures, and even death. The toxic oral dose can be as low as 5-6 grams for adults, and some supplements contain 600mg per capsule.

Key Points to Consider

  • If you've accidentally ingested boric acid, contact Poison Control immediately at 1-800-222-1222.
  • For vaginal health concerns that might lead someone to consider boric acid, consult a healthcare provider for appropriate treatment options.
  • Boric acid is only considered safe when used as directed for vaginal infections in specific formulations designed for that purpose, not as an oral supplement.
  • The toxicity occurs because when taken orally, boric acid is absorbed into the bloodstream at much higher levels than when used vaginally, leading to systemic effects throughout the body, as seen in cases reported in the literature 2, 3, 4, 5, 6.

Treatment and Prevention

  • Early treatment with forced diuresis and haemodialysis may be considered for boric acid poisoning, even if signs of renal dysfunction are not apparent, to prevent severe renal damage and its complications 3.
  • Forced diuresis without haemodialysis is recommended early after admission for boric acid poisoning 4.
  • It is essential to note that the risk of toxicity from ingesting one over-the-counter boric acid supplement orally can be significant, and immediate medical attention is necessary in case of accidental ingestion.

Evidence-Based Recommendation

Based on the most recent and highest quality study available, the risk of toxicity from ingesting one over-the-counter boric acid supplement orally is significant, and it should be avoided 3.

References

Research

A fatal case of acute boric acid poisoning.

Journal of toxicology. Clinical toxicology, 1993

Research

A case report of massive acute boric acid poisoning.

European journal of emergency medicine : official journal of the European Society for Emergency Medicine, 2010

Research

Usefulness of forced diuresis for acute boric acid poisoning in an adult.

Journal of clinical pharmacy and therapeutics, 2001

Research

Clinical manifestations of toxicity in a series of 784 boric acid ingestions.

The American journal of emergency medicine, 1988

Research

Fatal ingestion of boric acid in an adult.

The American journal of emergency medicine, 1992

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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