What would be the effects of ingesting 30 tablets of hydroxyzine (antihistamine) 25 milligrams each?

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From the FDA Drug Label

The most common manifestation of hydroxyzine overdosage is hypersedation. Other reported signs and symptoms were convulsions, stupor, nausea and vomiting. Hydroxyzine overdose may cause QT prolongation and Torsade de Pointes ECG monitoring is recommended in cases of hydroxyzine overdose.

If you took a whole bottle of 30 hydroxyzine 25mg each, you may experience:

  • Hypersedation
  • Convulsions
  • Stupor
  • Nausea and vomiting
  • QT prolongation and potentially Torsade de Pointes It is recommended to seek immediate medical attention, as treatment may involve gastric lavage, induction of vomiting, and close monitoring of vital signs 1.

From the Research

Taking a whole bottle of 30 hydroxyzine 25mg pills (750mg total) would be extremely dangerous and potentially fatal, requiring immediate emergency medical attention. This would be considered a significant overdose that can cause severe central nervous system depression, hypotension (dangerously low blood pressure), seizures, cardiac arrhythmias, and respiratory depression, as supported by the general understanding of hydroxyzine's effects 2, 3, 4, 5. The anticholinergic effects can include extreme drowsiness, confusion, dilated pupils, dry mouth, urinary retention, and hyperthermia.

Key Considerations

  • The therapeutic dosing of hydroxyzine is typically 25-100mg per day divided into multiple doses, making 750mg a significantly excessive amount 5.
  • Hydroxyzine has been studied for its efficacy in generalized anxiety disorder and sleep disorders, but such high doses are not recommended for any condition 2, 3, 4, 5.
  • Treatment for an overdose would likely involve gastric lavage (stomach pumping), activated charcoal, supportive care for vital functions, and possibly medications to counteract specific effects.

Recommendations

  • If you or someone else has taken this amount, call 911 or your local emergency number immediately.
  • If you're experiencing thoughts of self-harm, please contact a crisis helpline such as the National Suicide Prevention Lifeline at 988 or text HOME to 741741 to reach the Crisis Text Line.
  • Always follow the prescribed dosage and consult with a healthcare professional before taking any medication, especially in large quantities.

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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