Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0344307 (analgesia)
 28,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hemoglobin-(= Met-Hb)formation by local anaesthesia and local anaesthetics is still a point for discussion. Until now met-hb-aemia only was proven to develop under local anaesthetics with relationship to aniline (Benzocaine, Citanest). Since aniline does not possess any oxidative properties, met-hb-formation only can occur after metabolism (phenylhydroxylamine or para-aminophenol), first of all amino- and nitro-groups [6, 14] will be made responsible for oxidation. Because of the fact that neither the relationship to aniline nor the benzol-structure is the pre-supposition for met-hb-formation, possibly other substances with amino- or nitro-groups may induce it. In consequence of incidental cyanosis under intra and extradural analgesia we studied the met-hb-behaviour after the use of different local anaesthetics. The aniline-related bupivacaine and etidocaine were opposed to the thiophene-related carticaine. In this examination we found neither an elevation of hemoglobin by the aniline-related nor by the thiophene-related substances.
 ...
PMID:[Met-Hb formation and local anesthesia using bupivacaine, carticaine and etidocaine (author's transl)]. 724 10

Methemoglobinemia can cause life-threatening hypoxia associated with cyanosis and dyspnea not responsive to oxygen. We present a case of recurrent methemoglobinemia because of occult use of topical benzocaine to the vulva. A 47-year-old female with medical history of vulvar cancer and HIV undergoing chemoradiation was sent by the oncology clinic to the emergency department for worsening dyspnea, fatigue, hypoxia to 78% on room air, and gradual onset of cyanosis over the past week. A methemoglobin (MetHb) level was 49%. She received methylene blue, and repeat MetHb levels initially decreased but later increased to 56% despite continued treatment. Additional interviews with the patient revealed she was applying vagicaine (20% benzocaine), an over the counter preparation to the vulvar area for analgesia, and she continued application while hospitalized. She received a total of 6 mg/kg methylene blue and underwent vaginal lavage with 60 mL of sterile saline and cleansed with soapy water. Cyanosis, hypoxia, and dyspnea resolved, and the MetHb level decreased to 5.4% on the day of discharge. Benzocaine is a frequent cause of iatrogenic methemoglobinemia. In this case, additional medication inquiries were helpful in making the diagnosis. Many patients do not consider over-the-counter medications to be potentially harmful. Methemoglobinemia from occult topical benzocaine administration to the vulva is an uncommon exposure route. Occult medication use can be a source of methemoglobinemia.
 ...
PMID:Topical Benzocaine and Methemoglobinemia. 2775 90