Cannabis is often discussed as if the science has reached one simple answer on chronic pain. It has not. The 2025 update of the federal Agency for Healthcare Research and Quality living review offers a more useful conclusion: some specific cannabinoid preparations probably produce small short-term improvements for some adults, while common adverse effects increase and many popular products remain poorly studied.
Best supported: short-term use of certain THC-and-CBD oral sprays for mainly neuropathic pain. Effect size: small. Important harms: dizziness, sedation, and nausea. Evidence for whole-plant cannabis, many retail CBD products, long-term outcomes, and reduced opioid use remains limited or insufficient.
What the 2025 Review Included
The AHRQ report was the fourth and final annual update of a living systematic review. Its searches ran through April 28, 2025. The authors included 29 randomized controlled trials and 15 comparative observational studies, then grouped cannabis products by THC-to-CBD ratio and by whether the product was whole-plant, extracted, purified, or synthetic.
That grouping matters. “Cannabis” can refer to flower, an oral spray, a purified compound, a synthetic drug, a topical preparation, or a product with a very different THC-to-CBD ratio. A finding about one formulation should not be transferred automatically to every item sold at a dispensary or hemp store.
The Clearest Benefit Was Small
For adults with chronic pain—mainly neuropathic pain—an extracted oral spray with roughly comparable THC and CBD was probably associated with small improvements in pain severity and overall function versus placebo. The review rated that evidence moderate strength. “Small” is important: the average improvement was not a dramatic disappearance of pain.
High-THC purified or synthetic products may also produce a small pain improvement, but the certainty was lower. Low-THC-to-CBD products, including purified CBD alone, generally were not associated with improved pain or function in the evidence reviewed.
Side Effects Were Not a Footnote
The comparable THC-to-CBD oral spray may carry a large increase in dizziness and sedation and a moderate increase in nausea. High-THC products were also linked with more withdrawals due to adverse effects, sedation, nausea, and dizziness. These risks matter for driving, fall risk, work, alcohol use, and interactions with other medicines that cause drowsiness.
The report could not draw firm conclusions about several longer-term or serious outcomes, including cannabis use disorder, psychosis, cognitive effects, and the impact on opioid use. An absence of adequate evidence is not evidence that a risk is absent.
What the Review Does Not Prove
- It does not show that any retail product labeled “pain relief” will work.
- It does not establish that higher THC produces better results.
- It does not show that CBD alone reliably treats chronic pain.
- It does not prove that cannabis lets patients safely stop opioids.
- It does not settle long-term safety for daily use.
How to Read Pain-Product Claims
Look for the exact formulation, route, dose, comparison group, study length, and type of pain. A short trial of a standardized oral spray in neuropathic pain is not evidence for a high-potency vape marketed for back pain. Testimonials can describe one person’s experience but cannot establish average benefit, side-effect frequency, or causation.
For medical use, discuss the evidence with a clinician who knows the patient’s diagnoses, medicines, fall risk, mental-health history, and substance-use history. Do not stop a prescribed medicine because of a retail claim or an article. CannaWize reports the evidence; it does not prescribe a product or dose.
The Responsible Bottom Line
The current federal review supports neither “cannabis does nothing” nor “cannabis is a proven pain cure.” It supports a narrower statement: selected cannabinoid products can yield small short-term improvements for some chronic-pain patients, while adverse effects increase and large evidence gaps remain. That is less dramatic than marketing, but far more useful for an informed conversation.
Why Average Effects Can Hide Different Experiences
A trial reports an average across participants. Some people improve more than the average, some do not improve, and some stop because of adverse effects. That distribution is one reason a modest mean result can coexist with strong personal stories on both sides. It is also why a testimonial cannot tell another patient the probability of benefit.
Neuropathic pain made up much of the evidence base. Results should not be assumed to apply equally to inflammatory pain, low-back pain, migraine, cancer pain, acute injury, or pain in adolescents. The report also required at least four weeks of treatment, so it did not address questions about one-time use for acute pain.
Evidence Strength Is Not the Same as Effect Size
“Moderate evidence” describes confidence that the estimated result is reasonably close to the truth; it does not mean the benefit itself was moderate. In this review, the better-supported pain benefit was still small. A large side-effect risk can appear alongside a small average benefit.
That distinction should appear in news coverage and product pages. A headline that says “moderate evidence cannabis works” removes the size of the effect, the formulation, the pain population, and the adverse events—the details needed to understand the finding.
Questions for a Clinical Conversation
- What type of pain is being treated, and does the evidence address it?
- What measurable goal would count as worthwhile improvement?
- Which product and THC-to-CBD ratio are being considered?
- How will dizziness, sedation, mood change, and function be monitored?
- When will the plan be stopped if the benefit is too small?