COWS score: scoring, withdrawal, and buprenorphine

In this article▾

1. What is the COWS score?
2. How to calculate a COWS score
3. COWS score ranges
4. What does a COWS score of 5-12 mean?
5. What does a COWS score of 13-24 mean?
6. What does a COWS score of 25 or higher mean?
7. COWS score and buprenorphine induction
8. Why the COWS score at induction matters
9. Does the patient need a specific COWS score before buprenorphine?
10. COWS and fentanyl: why timing can be more complicated
11. COWS should be interpreted alongside objective signs
12. How to document a COWS assessment
13. COWS and level-of-care decisions
14. COWS and concurrent review
15. COWS and H0010
16. Common COWS documentation mistakes
17. COWS scoring quick reference
18. Frequently asked questions about COWS scores
19. Final takeaway
20. Sources

The COWS score, or Clinical Opiate Withdrawal Scale, is an 11-item clinician-administered instrument used to assess the severity of opioid withdrawal.

Each item is scored according to the patient's observed or reported symptoms. The maximum possible score is 48. The COWS assesses pulse rate, sweating, restlessness, pupil size, bone or joint aches, runny nose or tearing, gastrointestinal symptoms, tremor, yawning, anxiety or irritability, and gooseflesh skin.

For clinicians treating opioid use disorder, the COWS has another practical role: it helps document whether a patient is experiencing objective opioid withdrawal before buprenorphine is initiated.

That timing matters because administering buprenorphine before sufficient withdrawal has developed can cause or worsen precipitated opioid withdrawal. NIDA's buprenorphine guidance recommends confirming that the patient is experiencing opioid withdrawal before the first dose.

The COWS score is therefore both a clinical measurement and an important part of the induction record.

What is the COWS score?

The Clinical Opiate Withdrawal Scale was developed as an 11-item clinician-administered measure of opioid withdrawal. NIDA describes it as a tool that can be used in both inpatient and outpatient settings to reproducibly rate common opioid withdrawal signs and symptoms and monitor them over time.

The 11 domains are:

1. Resting pulse rate
2. Sweating
3. Restlessness
4. Pupil size
5. Bone or joint aches
6. Runny nose or tearing
7. Gastrointestinal upset
8. Tremor
9. Yawning
10. Anxiety or irritability
11. Gooseflesh skin

The instrument is explicit that each item is scored only for the component attributable to opioid withdrawal. An elevated heart rate caused by recent exercise is not withdrawal-related tachycardia, and the bone-and-joint-aches item says the same thing directly: if the patient already had pain, score only the additional component.

That distinction is important. A COWS score should reflect opioid withdrawal, not every abnormal finding present during the encounter.

How to calculate a COWS score

For each of the 11 items:

1. Assess the patient's current signs and symptoms.
2. Select the score that best describes the finding.
3. Attribute the finding to opioid withdrawal when clinically appropriate.
4. Add the 11 item scores.
5. Record the total and the time of assessment.

The maximum possible COWS score is 48.

Example

A patient presents after stopping an opioid and has:

The patient's COWS score is 19, which falls in the moderate withdrawal range.

The score should then be considered alongside the patient's opioid exposure, time since last use, clinical history, and treatment protocol.

COWS score ranges

The severity bands printed on the published instrument are:

Those bands come from Wesson and Ling's original scale and are printed on the form NIDA distributes.

A score below 5 does not mean opioid withdrawal is absent. It means the patient has not reached the mild range on this scale at that assessment.

The score should also be interpreted in context. COWS is a measurement of the patient's current withdrawal state, not a standalone diagnosis of opioid use disorder or a complete assessment of future withdrawal risk.

What does a COWS score of 5-12 mean?

A COWS score from 5 to 12 falls in the mild withdrawal range.

This range can be clinically important for buprenorphine induction because the patient may be developing objective withdrawal but may not yet have sufficient withdrawal for every induction protocol.

Induction timing follows the local protocol, and objective withdrawal is established before induction. Published thresholds cluster in the 8 to 12 range, but the facility's protocol is what governs.

ASAM's older induction flow sheet similarly describes waiting when withdrawal is insufficient and states that COWS scores above 10 are preferable in its conventional induction approach.

The practical point is that a COWS score of 5 is not a universal "start buprenorphine now" threshold.

What does a COWS score of 13-24 mean?

A score of 13 to 24 falls in the moderate withdrawal category.

For a patient being evaluated for standard buprenorphine induction, a score in this range generally provides stronger objective evidence that withdrawal is underway than a low or borderline score.

But the score is still only one component of the induction decision.

The clinician should also document:

• Opioid used
• Last reported use
• Pattern and amount of use when clinically relevant
• Whether other opioids were used
• Objective withdrawal findings
• Current intoxication or sedation
• Prior experience with buprenorphine
• Relevant medical and psychiatric considerations
• Induction strategy selected

The guidance is consistent on the principle even where the numbers differ: assess for opioid withdrawal and physiological dependence before the first buprenorphine dose, and COWS is the usual way to document it.

What does a COWS score of 25 or higher mean?

A COWS score of 25 to 36 is moderately severe withdrawal, and more than 36 is severe withdrawal.

These scores indicate substantial withdrawal symptoms and require clinical attention.

They do not, however, automatically determine the appropriate treatment setting.

The clinician should consider the patient's overall medical and psychiatric condition, withdrawal history, ability to participate in treatment, available monitoring, and other clinical factors.

Under the ASAM Criteria Fourth Edition, withdrawal sits in Dimension 1: Intoxication, Withdrawal, and Addiction Medications. Level-of-care recommendations come from the multidimensional assessment, not from a single withdrawal score. The levels of care guide covers what each setting can actually manage.

COWS score and buprenorphine induction

This is where COWS becomes particularly important.

Buprenorphine has high affinity for the mu-opioid receptor. If it is introduced while a full opioid agonist is still exerting substantial effects, it can displace the full agonist and produce precipitated withdrawal.

For conventional buprenorphine initiation, the patient should therefore have developed objective opioid withdrawal before the first dose.

SAMHSA's TIP 63 states that the patient should exhibit signs of opioid withdrawal before the first dose to avoid precipitated withdrawal. The number it gives is worth tracing: it cites the buprenorphine REMS, which indicates that a COWS score of 12 or higher is typically adequate for a first dose. That is a regulatory-programme figure quoted by a treatment protocol, not a clinical cutoff TIP 63 derived itself.

Sources: SAMHSA TIP 63, Medications for Opioid Use Disorder · NIDA: initiating buprenorphine in the emergency department

However, this should not be interpreted as a universal rule for every patient or induction strategy.

ASAM's more recent clinical considerations recognize that buprenorphine initiation may need to be individualized, particularly for people using high-potency synthetic opioids such as fentanyl. That guidance describes standard initiation as one option when opioid withdrawal is present and notes COWS 8 or above with at least one objective sign of opioid withdrawal in its clinical considerations table.

This difference illustrates why clinicians should document the actual protocol and clinical rationale, rather than simply writing "COWS 12 or higher required."

Why the COWS score at induction matters

The most important COWS score for documentation is often the score obtained immediately before the first buprenorphine dose.

That score establishes the patient's withdrawal state at the point when the medication was initiated.

For example:

COWS 11 at 0930. Patient reports last fentanyl use approximately 18 hours ago. Objective findings include dilated pupils, rhinorrhea, observable tremor, sweating, and restlessness. Patient is alert and not intoxicated or sedated. Per facility induction protocol, buprenorphine initiated following confirmation of objective withdrawal.

This is considerably more useful than:

"Started Suboxone when COWS was positive."

The record should show why the clinician believed the patient was in sufficient withdrawal to proceed.

Does the patient need a specific COWS score before buprenorphine?

There is no single COWS number that applies to every buprenorphine induction strategy and every opioid exposure.

For conventional induction, published guidance commonly uses objective withdrawal thresholds, with some protocols using COWS 8-12 or higher. SAMHSA's TIP 63 gives COWS 12 or higher as an example typically adequate for a first dose, while ASAM's 2023 clinical considerations describe standard initiation in patients with COWS 8 or above plus at least one objective withdrawal sign.

The appropriate threshold should therefore come from the protocol governing the patient's care and the clinician's assessment.

The severity bands are a description of withdrawal intensity. They are not an induction order, and induction timing follows the protocol governing the patient's care.

COWS and fentanyl: why timing can be more complicated

Patients exposed to fentanyl and other high-potency synthetic opioids may not follow the same withdrawal and induction patterns clinicians learned from older opioid exposures.

ASAM's Clinical Considerations for high-potency synthetic opioids states that buprenorphine initiation may require individualized strategies and emphasizes managing withdrawal before and during initiation.

The practical implication is not that every fentanyl-exposed patient requires a particular alternative induction method.

It is that clinicians should document:

• The opioid exposure known or suspected
• Time since last use
• Current withdrawal findings
• COWS score
• Objective withdrawal signs
• Induction strategy
• Patient response after initiation

A COWS score should inform the decision, but it should not be detached from the patient's opioid exposure and clinical presentation.

COWS should be interpreted alongside objective signs

The COWS contains both subjective and objective components.

For example:

• Pulse is measured.
• Pupils are observed.
• Tremor is observed.
• Restlessness is observed.
• Sweating is assessed.
• Some symptoms, such as aches or anxiety, depend substantially on patient report.

The NIDA COWS instrument notes that patients should generally exhibit observable signs or symptoms rather than simply reporting maximum severity across categories.

This is why documentation should not simply say:

"COWS 14."

Instead, identify the findings that produced the score.

How to document a COWS assessment

The surrounding history matters as much as the score, and OLDCARTS is a workable structure for it. A useful COWS note should include:

• Date and time
• Individual item scores
• Total COWS score
• Last opioid use
• Current opioid or suspected opioid exposure
• Objective withdrawal findings
• Current intoxication/sedation status
• Action taken
• Reassessment plan
• Response to treatment

The published form carries fields for date, time, reason for assessment and the rater's initials, and instructs the clinician to score only what is attributable to opioid withdrawal.

Example: Initial withdrawal assessment

COWS at 0900: 9. Patient reports last opioid use approximately 16 hours ago. Resting pulse 102, mild diaphoresis, frequent shifting, moderately dilated pupils, rhinorrhea, mild tremor, yawning twice, and mild anxiety. No GI symptoms or gooseflesh. Patient alert and not sedated. Continue withdrawal monitoring and reassess per protocol.

Example: Documentation immediately before buprenorphine

COWS at 1100: 13. Patient reports continued opioid abstinence since last assessment. Objective withdrawal findings include tachycardia, sweating, dilated pupils, restlessness, rhinorrhea, tremor, and yawning. No signs of intoxication or sedation. COWS reviewed before first buprenorphine dose. Standard induction initiated according to facility protocol. Patient to be reassessed following administration.

Example: Serial assessment

COWS: 0900 = 7; 1100 = 12; 1200 pre-induction = 14; 1400 post-induction = 8. Patient demonstrated increasing objective withdrawal before induction and subsequent improvement after treatment. Continue monitoring per protocol.

The exact numbers and findings should always reflect the actual assessment.

COWS and level-of-care decisions

COWS can provide important evidence for withdrawal-management needs, but it should not be converted directly into an ASAM level of care.

The ASAM Criteria Fourth Edition uses a multidimensional Level of Care Assessment. Dimension 1 includes intoxication, withdrawal, and addiction medication needs, while the broader assessment also considers biomedical, psychiatric/cognitive, substance-use-related, recovery-environment, and person-centered factors.

ASAM's current Level of Care Assessment Guide includes a field for the current COWS score alongside withdrawal history and addiction-medication needs, which is a good indication of how the instrument is meant to be used: as an input to the dimensional assessment, not a substitute for it. Our walkthrough of that assessment covers the rest of it.

That makes COWS particularly useful as supporting evidence within the broader assessment.

The clinical logic should look like:

COWS score → withdrawal severity → monitoring/treatment needs → multidimensional assessment → level of care

Not:

COWS score → automatic placement

COWS and concurrent review

For utilization review, the most useful record is a sequence of assessments showing the patient's changing clinical needs. Alcohol withdrawal has its own instrument and its own thresholds; see CIWA-Ar scoring if both are in play.

A reviewer can understand the case much more easily from:

COWS 7 → COWS 12 → COWS 15 → buprenorphine initiated → COWS 8 after treatment

than from a single statement:

"Patient admitted for opioid withdrawal."

Document the relationship between the score and the services provided.

For example:

"Patient's COWS increased from 7 to 14 over four hours with worsening restlessness, diaphoresis, rhinorrhea, tremor, and anxiety. Serial assessment was required to determine readiness for buprenorphine initiation. Following induction, COWS decreased to 8. Continued monitoring remains necessary due to ongoing withdrawal symptoms and need for medication adjustment."

This gives the reviewer the clinical trajectory, not just the instrument result.

ASAM's Fourth Edition service-request materials specifically prompt providers to include standard measures such as COWS scores for patients experiencing withdrawal, alongside the broader dimensional information used for authorization and continued service decisions.

COWS and H0010

COWS documentation can also be relevant when opioid withdrawal management is part of a billed withdrawal-management service.

For the coding side, see our H0010 code guide, and CO-50 for medical-necessity denials on withdrawal-management claims.

The important documentation principle is the same: the COWS score does not establish the service by itself.

The record should connect the patient's withdrawal symptoms to the clinical services delivered, including assessment, monitoring, medication management, and the need for the treatment setting.

Common COWS documentation mistakes

1. Recording only the total score

"COWS 12" does not show which withdrawal signs were present.

Record the individual findings when the scale is administered.

2. Using a COWS threshold as an automatic buprenorphine order

A particular threshold may be part of a facility protocol, but COWS thresholds vary by induction strategy and opioid exposure.

Document the protocol and clinical reasoning.

3. Recording the score after the first dose but not before it

The pre-induction score is particularly important because it documents the patient's withdrawal state when buprenorphine was initiated.

4. Ignoring the opioid exposure

Time since last use and the opioid involved can affect induction planning.

Document the relevant history.

5. Treating COWS as a diagnosis

COWS measures withdrawal symptoms. It does not establish OUD.

For diagnostic coding, see our opioid use disorder ICD-10 guide. Where more than one substance is in play, polysubstance coding covers the trap of defaulting to an unspecified code.

6. Using COWS as the sole level-of-care justification

COWS is one part of a multidimensional assessment. ASAM's Fourth Edition uses Dimension 1 alongside the other dimensions to inform level-of-care recommendations.

COWS scoring quick reference

The published instrument carries the full scoring anchors for each domain.

COWS severity ranges

These are the categories printed on the published instrument.

Buprenorphine induction quick reference

Published guidance does not establish one universal COWS threshold for every induction strategy. SAMHSA's TIP 63 gives COWS 12 or higher as an example typically adequate for a first dose in conventional initiation, while ASAM's 2023 high-potency-synthetic-opioid clinical considerations describe standard initiation when COWS 8 or above with at least one objective sign of opioid withdrawal.

Frequently asked questions about COWS scores

What is a COWS score?

COWS is the Clinical Opiate Withdrawal Scale, an 11-item clinician-administered instrument for measuring opioid withdrawal symptoms. The maximum score is 48.

What is a normal COWS score?

A score of 0 to 4 is below the mild withdrawal range. A low score means that relatively few withdrawal symptoms were present at that assessment; it does not by itself establish the patient's future withdrawal risk.

What is a COWS score of 8?

A score of 8 falls in the mild withdrawal category. Some current buprenorphine guidance considers COWS 8 or above plus at least one objective withdrawal sign sufficient for standard initiation, while other conventional protocols use higher thresholds. The applicable clinical protocol and patient presentation should determine timing.

What COWS score is needed to start buprenorphine?

There is no single threshold that applies to every patient and induction strategy. SAMHSA's TIP 63 gives 12 or higher as an example typically adequate for a first dose in conventional induction. ASAM's 2023 clinical considerations for patients exposed to high-potency synthetic opioids describe standard initiation at COWS 8 or above with at least one objective withdrawal sign.

Why does COWS matter before buprenorphine?

Buprenorphine should generally be started when sufficient opioid withdrawal has developed during conventional induction because starting it too early can cause precipitated withdrawal. The COWS provides a structured way to document the patient's withdrawal state before the first dose.

Does fentanyl change the COWS threshold?

Fentanyl and other high-potency synthetic opioids can make buprenorphine initiation more challenging. ASAM recommends individualized initiation strategies for patients exposed to high-potency synthetic opioids rather than relying on a single universal approach.

Does COWS determine the ASAM level of care?

No. COWS contributes to assessment of withdrawal and addiction-medication needs, but ASAM's Fourth Edition uses a multidimensional assessment to determine level-of-care recommendations.

Who developed the COWS?

Wesson and Ling, in a 2003 paper in the Journal of Psychoactive Drugs. It rates eleven common opiate withdrawal signs and symptoms, and the summed score supports inferences about the patient's level of physical dependence.

What is the maximum COWS score?

Forty-eight. The eleven items are not scored on the same scale: restlessness, pupil size, gastrointestinal upset and gooseflesh run 0 to 5, while the other seven run 0 to 4.

Should every abnormal finding be scored on the COWS?

No, and this is the most common scoring error. Each item is scored only for the component attributable to opioid withdrawal. Tachycardia from recent exertion is not withdrawal tachycardia, and on the bone-and-joint item the instrument says it directly: if the patient already had pain, score only the additional component.

Should the COWS score be documented before or after buprenorphine?

Ideally, document the pre-induction COWS score and time immediately before the first dose, then document subsequent assessments and response. The pre-dose score establishes the patient's withdrawal state at the time of induction. Record the score and the time immediately before the first dose; that pairing is what establishes the patient's state at induction.

Final takeaway

The COWS score gives clinicians a structured way to measure opioid withdrawal and track its progression.

For buprenorphine induction, its most important role is documenting that the patient has developed sufficient withdrawal before the first dose under the applicable induction protocol.

The strongest documentation connects:

opioid exposure → time since last use → objective withdrawal signs → COWS score → induction decision → response

The score should not be treated as an automatic medication order or an automatic level-of-care decision.

For conventional induction, published guidance commonly uses a COWS threshold in the mild-to-moderate withdrawal range, but the exact threshold varies. SAMHSA's TIP 63 gives COWS 12 or higher as an example typically adequate for a first dose, while ASAM's more recent guidance for high-potency synthetic opioid exposure describes standard initiation at COWS 8 or above plus at least one objective withdrawal sign.

For concurrent review, the most important record is therefore not simply "COWS = 12." It is a dated sequence showing the patient's withdrawal symptoms, the pre-induction score, the clinical rationale for starting buprenorphine, and the patient's response afterward.

Sources

1. Wesson, D. R., & Ling, W. (2003). The Clinical Opiate Withdrawal Scale (COWS). Journal of Psychoactive Drugs, 35(2), 253-259. pubmed.ncbi.nlm.nih.gov
2. National Institute on Drug Abuse. Clinical Opiate Withdrawal Scale [instrument PDF]. nida.nih.gov
3. Substance Abuse and Mental Health Services Administration. Medications for opioid use disorder (TIP 63). nida.nih.gov
4. National Institute on Drug Abuse. Initiating buprenorphine treatment in the emergency department. nida.nih.gov
5. American Society of Addiction Medicine. Clinical recommendations, including clinical considerations for buprenorphine treatment of OUD in individuals using high-potency synthetic opioids. asam.org
6. American Society of Addiction Medicine. The ASAM Criteria, Fourth Edition. asam.org

Related guides: CIWA-Ar scoring · CAGE questionnaire · Opioid use disorder ICD-10 · H0010 code guide · ASAM level of care assessment

Every source above was opened and checked on October 4, 2026. This is educational content and does not replace the published instrument, your facility's induction protocol, or clinical judgment.