What Is the Medical Treatment Utilization Schedule (MTUS)?

The Medical Treatment Utilization Schedule (MTUS) is California’s official set of treatment guidelines for workers’ compensation. It is the yardstick insurers use in utilization review, and independent medical reviewers use on appeal, to decide whether the care your doctor requests is medically necessary. Treatment that follows the MTUS is presumed correct, and treatment outside it is harder, but not impossible, to get approved.

What the MTUS is

The Division of Workers’ Compensation adopts the MTUS under Labor Code §5307.27, and the DWC’s MTUS page describes it as based on the principles of evidence-based medicine. Labor Code §4600 ties your right to medical treatment to these guidelines: treatment is “reasonably required” when it is based on the guidelines the state has adopted.

ACOEM guidelines are the core of the MTUS. The schedule also includes a drug formulary, the MTUS Drug List, which has applied since January 1, 2018, with updates to the drug list taking effect April 30, 2026.

What the MTUS covers

The MTUS includes body-part and condition guidelines, each adopted by an Administrative Director order. Recent effective dates shown on the DWC’s page include:

Other guidelines cover eye disorders, occupational asthma and interstitial lung disease, initial assessment and treatment, work disability prevention, and more. Acupuncture and postoperative rehabilitation are addressed within the MTUS without stand-alone guidelines. The DWC updates guidelines regularly, so the version in effect when your doctor’s request is reviewed is the one that applies. If you are treating for long-term pain, our pain management guide explains how pain treatment is requested and authorized.

How the MTUS affects your treatment requests

1. Your doctor submits a Request for Authorization (RFA). The request should explain how the treatment fits the MTUS. See our guide to requests for authorization.
2. The insurer runs utilization review (UR). UR decisions must be consistent with the MTUS. Routine decisions are due within five normal business days of receiving the request and never more than 14 days from the doctor’s recommendation; urgent requests within 72 hours (see our explainer on Labor Code §4610). Learn more about utilization review.
3. You can appeal a denial or modification through independent medical review (IMR). The request is generally due within 30 days after the UR decision is served on you, or 10 days for formulary disputes (Labor Code §4610.5(h)). IMR reviewers decide medical necessity using the MTUS. See independent medical review.

The presumption of correctness and how to rebut it

Under Labor Code §4604.5 and 8 CCR §9792.21, MTUS guidelines are presumptively correct on the extent and scope of medical treatment. The presumption is rebuttable: a treating physician who wants care outside the guidelines must show, by a preponderance of the scientific medical evidence, that the variance is reasonably required to cure or relieve your injury.

In practice, that means the doctor’s request should cite the specific studies or other guidelines that support the treatment for a patient like you, and explain why the MTUS recommendation doesn’t fit. A request that simply says “patient needs more therapy” is unlikely to overcome the presumption.

When the MTUS doesn’t address your condition

Treatment may not be denied on the sole basis that the condition or injury isn’t addressed by the MTUS. In that situation, care can be based on other evidence-based guidelines or peer-reviewed studies, found through the MTUS’s medical evidence search sequence, which starts with the ACOEM guidelines adopted into the MTUS and then moves to other sources. When competing recommendations exist, reviewers must weigh the quality of the underlying studies, with higher levels of evidence taking priority.

The 24-visit cap on therapy and chiropractic care

For injuries on or after January 1, 2004, Labor Code §4604.5(c) generally limits each injury to 24 chiropractic visits, 24 occupational therapy visits and 24 physical therapy visits. The cap doesn’t apply when the employer authorizes additional visits in writing, or to post-surgical physical medicine provided under the post-surgical treatment rules.

Common reasons requests are denied

• The requested amount or duration of treatment exceeds what the guideline recommends.
• The records don’t show functional improvement from earlier treatment.
• The request lacks the documentation the guideline calls for, such as specific exam findings or prior conservative care.
• Medication requests don’t match the MTUS Drug List rules or the opioid guideline.
• The request doesn’t cite any evidence for treatment outside the guidelines.

A hypothetical example

Marcus injures his lower back loading trucks. After 24 physical therapy visits, he is improving but still can’t lift at work. His doctor requests eight more sessions. UR denies the request, citing the visit cap and the low back guideline. Because Marcus didn’t have surgery, the cap applies unless his employer authorizes more visits in writing.

His doctor then requests a different, guideline-supported treatment and documents his functional gains in each report, showing measurable progress in lifting and walking tolerance. Marcus also requests IMR on the first denial within 30 days. Careful documentation of function is what gives a later request a fair chance.

What you can do

• Track your function, not just pain. Tell your doctor what you can lift, how long you can sit or stand, and what daily tasks have improved.
• Keep every UR letter. Each one starts an IMR deadline.
• Ask your doctor to cite the guideline. Requests that reference the MTUS section, or the evidence for a variance, are stronger.
• Consider changing doctors if requests keep failing. See our page on medical treatment rights in California.

Frequently asked questions

Does the MTUS apply to every California workers’ comp claim?

The MTUS is the standard of care for all injured workers diagnosed with industrial conditions, and UR and IMR decisions must follow it.

Can I get treatment the MTUS doesn’t recommend?

Possibly. Your doctor must rebut the presumption with a preponderance of scientific medical evidence showing the treatment is reasonably required for your injury.

What if my condition isn’t covered by any MTUS guideline?

Treatment can’t be denied just for that reason. Your doctor can rely on other evidence-based guidelines or peer-reviewed studies.

How long do I have to appeal a UR denial?

Generally 30 days after the UR decision is served on you, or 10 days for drug formulary disputes. Check the deadline stated in your UR letter.

Who pays for IMR?

The employer pays the cost of IMR.

Talk to a California workers’ comp lawyer

Employees First Labor Law represents workers exclusively, including injured workers whose treatment has been denied or delayed. We offer free virtual consultations to review your UR denials and options. Contact us online or call (310) 853-3461.

This article is general information about California law as of 2026, not legal advice for your situation. Reading it does not create an attorney-client relationship.