Most Common Adverse Reaction to Sodium Thiosulfate
The most common adverse reaction to sodium thiosulfate is nausea and vomiting.
Evidence from FDA Drug Label
The FDA prescribing information for sodium thiosulfate clearly identifies the adverse event profile 1. While controlled clinical trials have not been conducted to systematically assess adverse events, the medical literature and clinical experience consistently report:
Gastrointestinal system: nausea, vomiting
Other reported adverse events include:
- Cardiovascular: hypotension
- Central nervous system: headache, disorientation
- Hematological: prolonged bleeding time
- Body as a whole: salty taste in mouth, warm sensation over body
Clinical Context and Frequency
The FDA label specifically notes that rapid administration of concentrated solutions or large doses of sodium thiosulfate have been associated with a higher incidence of nausea and vomiting 1. In one documented series, administration of 0.1 g sodium thiosulfate per pound (up to maximum 15 g) in a 10-15% solution over 10-15 minutes was associated with nausea and vomiting in 7 of 26 patients (27%) without concomitant cyanide intoxication 1.
Supporting Evidence from Clinical Trials
In the ACCL0431 trial examining sodium thiosulfate for ototoxicity prevention in children with cancer, the most common adverse events were hematological (neutropenia) related to chemotherapy rather than sodium thiosulfate itself. Importantly, of 194 serious adverse events reported in 26 participants who received sodium thiosulfate, none were deemed probably or definitely related to sodium thiosulfate 2.
A systematic review of sodium thiosulfate use in dialysis patients confirmed that the most common adverse events were temporary nausea and vomiting, occurring in 12.5 to 75% of patients 3.
Important Clinical Caveats
- Administration rate matters: Slower infusion rates reduce the incidence of nausea and vomiting
- Hypotension and tachycardia can occur but are less common than gastrointestinal symptoms
- Metabolic acidosis with increased anion gap has been reported with prolonged use 4
- Minor side effects of headache and rhinorrhea may occur if infused too rapidly 4
The answer is clearly nausea and vomiting as the most common adverse reaction.