Concussion rules by body: each level writes its own.

The rules side by side

These are separate rules for separate settings. A player at a World Lacrosse championship, a US college player, a US high school player and a Canadian box player fall under different documents, and some also fall under a state or provincial law.

World Lacrosse (international events)

World Lacrosse's policy is titled "Concussion Policy: Identification, Treatment, and Management" and is marked approved in August 2020. It defines concussion as a brain injury caused by biomechanical forces, and sets three aims: recognise every concussive injury, take any player suspected of one out of play for evaluation, and provide rest and a graduated return-to-play protocol. This page does not describe that protocol.

• Scope. The policy applies at all World Lacrosse events, to every team, in scheduled games, scheduled team practices and pre-event games arranged through the host or World Lacrosse. Regional confederations must adopt it for World Lacrosse approved events (section 4).
• Officials. Any game official who may stop play for an injury may stop it for a suspected concussion, and a player the official declares suspected must leave play for evaluation (section 8).
• Clearance. A player declared to have a concussion needs medical clearance before returning. If the team doctor and the event medical officer disagree, the World Lacrosse or event medical officer decides (section 9).
• Medical cover and reporting. Hosts of world events must provide a licensed medical doctor as Event Medical Officer, with a doctor or trained first responder on site for every game (section 6). Teams file an injury report after each game, including confirmed and suspected concussions (section 7).
• History. The policy was first released in June 2016. Its appendix records the assessment tool World Lacrosse's Chief Medical Officer specified over time: none before June 2016, SCAT3 from June 2016 and SCAT5 from May 2019, confirmed in June 2020.

On 23 October 2026 World Lacrosse's health and safety page linked SCAT6, an Event Medical Manual whose file name is dated November 2025 and a 2022 concussion presentation to officials, but no policy newer than August 2020. Whether a later edition of the policy exists is unconfirmed.

USA Lacrosse (US youth and adult programmes)

USA Lacrosse's health and safety page (read 23 October 2026) lists Concussion Management Plan Guidelines dated June 2023, links the CDC's HEADS UP resources, and recommends a written concussion management plan as a first step for local programmes.

The guideline documents themselves, in their November 2022 and June 2023 versions, returned errors when the research tried to open them on 23 October 2026. Search summaries of those documents describe them as guidance for teams, clubs and leagues to consider rather than a standard of care, say a player diagnosed with or suspected of concussion should not return to activity for the rest of that day, say return to school and to play should be supervised by a physician or qualified healthcare professional, and tell organisations to check their state's law on who may give clearance. Those points rest on search summaries only and are unconfirmed here; USA Lacrosse's current documents are the authority.

NCAA (US college)

NCAA concussion rules apply to all sports, so they cover men's and women's lacrosse alike.

• Reporting. In January 2020 all three divisions adopted legislation (Division I Constitution 4.3.4.21, Division II Constitution 3.3.4.18, Division III Constitution 3.2.4.18) requiring active member schools to report every diagnosed sport-related concussion and its resolution each year, on a 1 July to 30 June cycle.
• Policy. The NCAA Board of Governors endorsed the concussion Interassociation Recommendations as association-wide policy in summer 2019, and schools in all three divisions must comply. Each member school must have a concussion management plan and is expected to support concussion education for athletes, coaches and staff.
• 2026 update. The Committee on Competitive Safeguards and Medical Aspects of Sports approved changes to the Concussion Safety Protocol Checklist, the protocol template and the fact sheets at its June 2026 meeting, with key updates effective 1 July 2026. A Concussion Safety Advisory Group reviews the checklist every year. Schools need not use the NCAA template, but their protocols must meet divisional legislation.
• Medical staff. For contact and collision sports, schools must have medical staff trained in concussion present at competitions and available at practices. The NCAA page names flag football and stunt as additions to that list but does not itself list lacrosse, so which lacrosse disciplines the NCAA classes as contact or collision sports is unconfirmed here.
• Research. In May 2014 the NCAA and the US Department of Defense announced the CARE Consortium, a joint concussion research effort planned to take baseline assessments of more than 37,000 student-athletes over three years.

NFHS (US high school)

The NFHS writes separate boys' and girls' lacrosse rule books, and neither was read for this site because they are sold rather than posted. The NFHS Sports Medicine Advisory Committee first published concussion guidance in February 2010. A February 2011 adaptation of that guidance by the Vanderbilt Sports Concussion Center says any athlete removed from play for a concussion should have medical clearance from an appropriate health care professional before returning to play or practice, that the guidance no longer allows a return for an athlete who seems clear after 15 minutes, and that it must not replace the central role of physicians and athletic trainers.

A New Hampshire state association document for boys' lacrosse in 2025, seen only in a search summary, quotes the NFHS rule as requiring immediate removal of any athlete showing signs, symptoms or behaviours consistent with concussion, with no return until cleared by an appropriate health care professional, and the summary dates that wording to the 2010-11 rule books. The current 2026 rule numbers and wording are unconfirmed.

One related equipment rule is confirmed from the NFHS's own change summary: from 2026, losing a helmet in boys' lacrosse is an illegal procedure, a technical foul (Rule 6-5-2y), which the Tennessee state association's report of 19 August 2025 describes as encouraging proper helmet and chin-strap use. It is a rule about wearing a helmet properly, not a concussion rule.

Lacrosse Canada

Lacrosse Canada's Concussion Policy, in a file posted in March 2025, states that concussion is a clinical diagnosis only a physician can make. A participant with a suspected concussion, even without loss of consciousness, may not return to play until they have consulted a physician, and every possible concussion must be reported to Lacrosse Canada. A copy of the physician's medical clearance letter must also be sent to Lacrosse Canada. The policy says failure to follow it may lead to discipline under Lacrosse Canada's safety policies.

The policy text is undated and says its next review would follow the 6th International Consensus Conference on Concussion in Sport in spring 2021, so the text appears to be older than its 2025 file date. Whether a newer edition exists is unconfirmed.

Who may diagnose: two Lacrosse Canada documents differ. The policy says only a physician. A search summary of Lacrosse Canada's separate Concussion Management Guidelines, a file too large for the research to open, says a medical doctor or nurse practitioner.

Laws, named only

Some governments have written concussion rules into law. They are named here so readers know they exist; the laws themselves, not this page, say what they require.

• Washington State, Zackery Lystedt Law. Signed on 14 May 2009; the University of Washington calls it the first comprehensive US law of its kind. The university says similar laws have since been adopted in all 50 states.
• Ontario, Rowan's Law (Concussion Safety), 2018. Royal Assent in March 2018, with its awareness phase in force from 1 July 2019 and its removal-from-sport and return-to-sport phase from 1 January 2022. The Government of Ontario describes it as the first and only comprehensive concussion safety legislation in Canada.
• United Kingdom, Concussion Guidelines for Grassroots Sport. Published by the UK Government on 28 April 2023 under the heading "If in doubt, sit them out". These are guidelines, not a law, and the government's release does not name lacrosse.

What this page does not cover

No England Lacrosse or Lacrosse Australia concussion policy was found, and no NCAA or NFHS lacrosse-specific concussion text was read from a rule book. Whether helmets or headgear change concussion rates is on the headgear debate, and how often concussion appears in injury studies is on injuries named.