A structural analogue of gamma-amino-butyric-acid (GABA). Likely increases the concentration of GABA in the brain.

Oral (300 - 400 mg) every 8 hr for 4 days

Decreases VAS score for 5 days [52]


Corticosteroid hormone receptor agonist.

IV (200 mg) and then 100 mg three times a day (oral) for 48 hours

Decreased VAS score by 50% 6 hrs later and 75% 24 h after treatment [53] [54]

Sodium retention-related weight gain, fluid accumulation, hyperglycemia, hypokalemia, gastrointestinal ulceration, mood changes


Synthetic adrenocorticotropic hormone (ACTH). Stimulates the adrenal gland to increase CSF production and β-endorphin output. Fluid and electrolyte retention.

60 units IM

1.5 units/kg IV

Pain relief at days 3 - 7 [55] Multiple studies have showed efficacy [51] [56] [57]

Caution in patients with diabetes and hypertension due to increased blood glucose levels and fluid and electrolytes retention [55] [58]