Many a migraine headache is encountered in the ED. The evidence is reasonably clear that the antiemetics (prochlorperazine/metoclopramide – Compazine/Reglan) combined with ketorolac (Toradol) will treat >90% of patients effectively. What about those that don’t respond and are still in (dramatic pause) status migrainosus.
The intravenous dose is 15-20 mg/kg IV (max of 1 gram). It turns out that a faster infusion rate – 10 minutes as opposed to 1 hour that had been given for seizure patients as oral replacement – was more effective. What you do next depends on their response.
The headache is completely gone or substantially improved
Start oral dosing within 4 hours of the IV dose. Generally it is efficient to give this in the ED before the patient goes home. Then prescribe a 14 day course.
- <10years OR <50kg: 250 mg PO BID x2 weeks
- ≥10years AND 50kg: 500 mg PO BID x2 weeks
The headache is improved, but not to a satisfactory degree
Repeat a 2nd IV dose within 3 hours. If that works then proceed to oral dosing as above. If it doesn’t then plan for additional therapy – likely DHE and inpatient admission.
Why not Depakote first, well Tanen compared the two in 2003 and noted the following. In a RCT of Prochlorperazine 10mg vs Valproate 500mg the latter was less effective in reducing pain and nausea (p<0.001). 79% of the Valproate group needed rescue medicine versus only 25% of the prochloroperazine group.
Want to learn more? Check out these articles:
- Reiter PD, Nickisch J, Merritt G. Efficacy and Tolerability of Intravenous Valproic Acid in Acute Adolescent Migraine. Headache 2005;45:899-903.
- Schwartz TH, Karpitskiy VV, Sohn RS. Intravenous Valproate Sodium in the Treatment of Daily Headache. Headache 2002;42:519-22.
Again, this is for abortive treatment – not preventative.