US EMS Protocol Census
Indication

Diphenhydramine for Nausea / vomiting

1,335 under review27 sources23 named agencies13 statesas of 2026-09-20

Adult dosing has a median of 25 mg across 27 published protocols, with the middle half between 12.5 and 25.

27sources
23named agencies
13states
53entries
22named here

1,335 rows are under review across the census and excluded from every number on this page. How that works.

Adultmg

27sources
23named agencies
13states
29entries
0kept as written
minp25medianp75max
12.512.5252550

Values in mg. One value per source (that source's median), so a document listing a drug five times still gets one vote.

Routes

  • IV/IM 45%
  • IV/IO/IM 21%
  • IV 17%
  • IM 7%
  • IO/IM 3%
  • IV/IO/IM/PO 3%
  • PO 3%

United States EMS Protocol Census, n=27 protocols from 23 named agencies / 13 states, updated Sep 2026

Pediatric, weight-basedmg/kg

20sources
18named agencies
9states
22entries
0kept as written
minp25medianp75max
11111.5

Values in mg/kg. One value per source (that source's median), so a document listing a drug five times still gets one vote.

Routes

  • IV/IM 50%
  • IV/IO/IM 23%
  • IM 9%
  • IV 9%
  • IO/IM 5%
  • IV/IO/IM/PO 5%

United States EMS Protocol Census, n=20 protocols from 18 named agencies / 9 states, updated Sep 2026

Adult, weight-basedmg/kg

1sources
1named agencies
1states
1entries
0kept as written

Below 5 sources, so no distribution is published for this group — only the counts above.

Routes

  • IV 100%

United States EMS Protocol Census, n=1 protocols from 1 named agencies / 1 states, updated Sep 2026

Pediatricmg

1sources
1named agencies
1states
1entries
0kept as written

Below 5 sources, so no distribution is published for this group — only the counts above.

Routes

  • IV/IM/PO 100%

United States EMS Protocol Census, n=1 protocols from 1 named agencies / 1 states, updated Sep 2026

Named agencies

Agencies whose protocols are a public record are named here. Their own doses are on their own pages; this list carries no values.