A phase III, randomized, multicenter, open label clinical trial to evaluate efficacy and safety of the injectable association of dexamethasone, dipyrone, and hydroxocobalamin in lumbar sciatic pain. The study will enroll 140 patients in each arm (280 total).

Inclusion Criteria:

• Sign the study informed consent form;
• To be diagnosed with moderate to severe lumbar sciatic pain (defined as limiting the work activities or the ordinary tasks performance or at the investigator's discretion) within the last 3 days;
• Aged 18 to 75 years old;
• To be able to meet the study procedures

Exclusion Criteria:

o-Diagnosed with chronic rheumatologic diseases, except recurrent lumbar sciatic pain;

• Patients with one of the following conditions, as per the investigator's criteria:
• Severe renal failure under hemodialysis, severe liver failure, uncontrolled severe heart failure;
• Severe injuries on gastrointestinal tract;
• Other severe comorbidities;
• Patients taking acetylsalicylic acid or any anti-clotting;
• Female patients who are pregnant, lactating, willing to get pregnant or not willing to use an appropriate contraceptive method during the study period.