Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The safety of PROVAYBLUE in adults with acquired methemoglobinemia was assessed in 31 patients who received at least 1 dose of PROVAYBLUE [see Clinical Studies (14)]. Most doses administered were 1 mg/kg (82.9%), but doses from 0.78 mg/kg to 2 mg/kg were administered. All patients received at least one dose of PROVAYBLUE; two received two doses, and one received three doses. Serious adverse reactions occurred in 3.2% of patients who received PROVAYBLUE. A serious adverse reaction of seizure-like phenomenon was reported in one patient. Adverse reactions (≥2%) included headache, hypokalemia, diarrhea, hypomagnesemia, myoclonus, nausea, and seizure-like phenomena.
The safety of PROVAYBLUE in pediatric patients with acquired methemoglobinemia was assessed in two retrospective case series that included two pediatric patients treated with PROVAYBLUE and 12 treated with another methylene blue product. The case series included patients in the following age groups: 3 neonates (<1 month), 4 infants (1 month to <2 years), 4 children (2 years to <12 years), and 3 adolescents (12 years to <17 years). The safety profile in pediatric patients was similar to that in adult patients.
Other adverse reactions reported to occur following the administration of methylene blue class products include the following:
Blood and lymphatic system disorders: hemolytic anemia, hemolysis, hyperbilirubinemia
Cardiac disorders: palpitations, tachycardia
Eye disorders: eye pruritus, ocular hyperemia, vision blurred
Gastrointestinal disorders: abdominal pain lower, dry mouth, flatulence, glossodynia, tongue eruption
General disorders and administration site conditions: death, infusion site extravasation, infusion site induration, infusion site pruritus, infusion site swelling, infusion site urticaria, peripheral swelling, thirst
Investigations: elevated liver enzymes
Musculoskeletal and connective tissue disorders: myalgia
Renal and urinary disorders: dysuria
Respiratory, thoracic and mediastinal disorders: nasal congestion, oropharyngeal pain, rhinorrhea, sneezing
Skin and subcutaneous tissue disorders: necrotic ulcer, papule, phototoxicity
Vascular disorders: hypertension