Taking a double-dose of a single medication is presumed to be safe in most cases. However, there is limited data to support this assumption.
A retrospective study of the California Poison Control System was performed to assess adverse effects of taking double dose of a single medication. During a 10-year period, 876 cases of double-dose ingestion of single medication were identified.
Adverse effects were rare (12 cases). However, medication classes that were involved in severe adverse effects included:
Propafenone: ventricular tachycardia and syncope
Beta blockers (BB): bradycardia and hypotension
Calcium channel blockers (CCB): bradycardia and hypotension
Bupropion: seizure
Tramadol: ventricular tachycardia
Conclusion:
Adverse effect from double dosing is rare.
Cardiovascular collapse can occur with BB and CCB
Seizure can occur with tramadol and bupropion.
References
Correia MS et al. A 10-year review of single medication double-dose ingestions in the nation's largest poison control system. Clin Toxicol 2018 Nov 28:1-5. doi: 10.1080/15563650.2018.1493205. [Epub ahead of print]
