Related Experiment Videos
Pheniramine--a much abused drug
N A Buckley1, I M Whyte, A H Dawson
1Department of Clinical Pharmacology and Toxicology, Newcastle Mater Misericordiae Hospital, Waratah, NSW.
The Medical Journal of Australia
|February 21, 1994
Summary
Pheniramine is disproportionately used in self-poisoning cases compared to its market share and is more likely to cause seizures. Regulatory bodies should review its over-the-counter availability.
Area of Science:
- Pharmacology
- Clinical Toxicology
- Public Health
Background:
- Antihistamines are commonly used for allergic conditions.
- Overdose of antihistamines can lead to significant clinical toxicity.
- Pheniramine is a first-generation antihistamine with potential for abuse and toxicity.
Purpose of the Study:
- To compare the clinical toxicity of pheniramine with other antihistamines in overdose settings.
- To assess the relative frequency of pheniramine use in self-poisoning incidents.
- To investigate the association between pheniramine overdose and specific adverse outcomes like seizures.
Main Methods:
- A prospective follow-up cohort study was conducted.
- Data on antihistamine self-poisonings were collected from hospital admissions.
- Pharmacist surveys were used to determine the market share of pheniramine.
Main Results:
- Pheniramine constituted 33.9% of self-poisoning cases despite a low market share (3.0% of items dispensed).
- Pheniramine overdose was significantly associated with generalized seizures (13/43 cases) compared to other antihistamines (1/75 cases).
- A high proportion of pheniramine overdose patients had a history of drug or alcohol abuse (79.9%), including antihistamine abuse (60.5%).
Conclusions:
- Pheniramine is overrepresented in self-poisoning incidents relative to its availability and shows a higher propensity for abuse.
- Pheniramine appears to be more proconvulsant in overdose than other antihistamines.
- Consideration should be given to alternative antihistamines for individuals at risk of seizures, and regulatory review of pheniramine's over-the-counter status is warranted.