Name of product: Methylene blue Dosage form: Injection (i.v.) Strength: 50 mg/5 mL Pack size: 5 vials Manufacturer: The Thai Red Cross Society (Thailand)

Uses

Contraindications

severe renal impairment; methaemoglobinaemia due to chlorate or induced by sodium nitrite in treatment of cyanide poisoning

severe renal impairment; methaemoglobinaemia due to chlorate or induced by sodium nitrite in treatment of cyanide poisoning, G6PD deficiency (may cause haemolytic anaemia)

May be diluted in 50 mL D5W to avoid local pain, especially in pediatric patients; use immediately after preparation
Avoid diluting with sodium chloride solutions
Inject IV over 5 to 30 minutes

Acute methemoglobinemia
- ADULT and CHILD: 1 – 2 mg/kg as a single dose (0.1 - 0.2 mL/kg of 1% solution) as a single dose; may be repeated after 1 hour if required

nausea, vomiting, abdominal pain, chest pain, headache, dizziness, confusion, profuse sweating; hypertension or hypotension reported; haemolytic anaemia methaemoglobinaemia (with high dosage); bluish skin discoloration; blue saliva, urine and faeces

Reference

Howland MA. Methylene blue. In: Lewis S. Nelson, Howland MA, Lewin NA, Smith SW, Goldfrank LR, Hoffman RS, editors. Goldfrank’s Toxicologic Emergencies. 11th ed. New York: McGraw-Hill Education; 2019. p. 1713–7.
Garza F, Kearney TE. Methylene blue. In: Olson KR, Anderson IB, Benowitz NL, Blanc PD, Clark RF, Kearney TE, et al., editors. Poisoning & Drug Overdose. 7th ed. New York: McGraw-Hill Education; 2018. p. 579–81.
Methylene blue. In: IBM Micromedex® DRUGDEX® (electronic version). IBM Watson Health, Greenwood Village, Colorado, USA. Available at: https://www.micromedexsolutions.com/ (cited: Mar/21/2022).