COWS (Clinical Opiate Withdrawal Scale)

What goes into the COWS (opioid withdrawal)

• Resting pulse: ≤ 80 (0); 81–100 (1); 101–120 (2); > 120 (4)
• Sweating (past 30 min): None (0); Barely perceptible (1); Beads on brow or face (2); Sweat streaming off face (4)
• Restlessness: Able to sit still (0); Reports difficulty sitting still (1); Frequent shifting or extraneous movements (3); Unable to sit still for more than a few seconds (5)
• Pupil size: Normal or pinned (0); Possibly larger than normal (1); Moderately dilated (2); Only iris rim visible (5)
• Bone or joint aches: None (0); Mild diffuse discomfort (1); Severe diffuse aching (2); Rubbing joints, unable to sit still (4)
• Runny nose or tearing: None (0); Nasal stuffiness or moist eyes (1); Runny nose or tearing (2); Constant running or streaming tears (4)
• GI upset (past 30 min): None (0); Stomach cramps (1); Nausea or loose stool (2); Vomiting or diarrhea (3); Multiple episodes (5)
• Tremor (outstretched hands): None (0); Felt, not seen (1); Slight tremor (2); Gross tremor or twitching (4)
• Yawning: None (0); Once or twice (1); Three or more times (2); Several times a minute (4)
• Anxiety or irritability: None (0); Reports it (1); Obviously irritable or anxious (2); Unable to participate in assessment (4)
• Gooseflesh skin: Smooth (0); Piloerection felt or hairs standing (3); Prominent piloerection (5)

How to interpret the result

• 5–12: mild
• 13–24: moderate
• 25–36: moderately severe
• > 36: severe
• Buprenorphine is usually started at COWS ≥ 8–12

Clinical pearls

• With fentanyl use, precipitated withdrawal is more common; wait for a higher score or use a low-dose induction.
• If precipitated withdrawal occurs, giving more buprenorphine usually helps.
• Since 2023 any clinician with a DEA Schedule III registration can prescribe buprenorphine for opioid use disorder.

Evidence

1. Wesson DR, Ling W. The Clinical Opiate Withdrawal Scale (COWS). J Psychoactive Drugs. 2003;35:253-259.

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