💊 Opioid agonist · Schedule II high-alert

Hydrocodone: Nursing Drug Guide, Respiratory Depression & NCLEX Review

Hydrocodone bitartrate and acetaminophen can cause fatal respiratory depression—especially with benzodiazepines, sleep apnea, COPD, or dose increases. Nurses must verify tablet strength, count daily maximums for both hydrocodone and hidden APAP, and assess ventilation before every dose.

⏱️14 min read
📅Updated May 27, 2026
Pharmacist Reviewed
🚨 Major safety note — Life-threatening respiratory depression

Hydrocodone bitartrate and acetaminophen tablets can cause serious, life-threatening, or fatal respiratory depression, especially during initiation or following a dose increase. Concomitant benzodiazepines, other CNS depressants, or alcohol may cause profound sedation, coma, and death. Combination products also contain acetaminophen—cumulative APAP from multiple sources can cause acute liver failure. Highest-risk patients include those with COPD, sleep apnea, renal or hepatic impairment, and the elderly. Assess respiratory rate, sedation, and oxygenation before every dose; ensure naloxone access per labeling when risk factors exist.

Quick facts

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Class
Opioid agonist (Schedule II)
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Route
Oral tablet
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Usual adult dose
1–2 tabs q4–6h PRN
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Main risk
Respiratory depression

💡 Key takeaway

Before every hydrocodone dose, assess respiratory rate, oxygen saturation, and arousability—and reconcile cumulative tablets and acetaminophen from all sources. An acceptable pain score never overrides inadequate ventilation.

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Most common brand names

Most inpatient and outpatient hydrocodone orders are for combination tablets containing hydrocodone bitartrate plus acetaminophen (APAP). Always verify strength on the MAR—5/325, 7.5/325, and 10/325 refer to hydrocodone mg per acetaminophen mg per tablet, not total daily limits.

Common combination brands include Norco, Vicodin, Lortab, and numerous generics. Single-entity hydrocodone products exist in some markets; institutional formularies vary. Do not assume two combination products are interchangeable without checking both opioid and acetaminophen content.

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Why we give it — Indications

Hydrocodone bitartrate and acetaminophen tablets are indicated for pain severe enough to require an opioid analgesic when alternative treatments are inadequate. Reserve opioids for patients who cannot tolerate or do not obtain adequate relief from non-opioid options, and limit duration when possible per prescribing information.

Use Detail
Moderate to severe acute pain Short-term analgesia after surgery, injury, or acute painful conditions when non-opioid analgesics are insufficient—many acute pain episodes require only a few days of opioid therapy per labeling.
Limitations of use Because of addiction, abuse, and misuse risks at any dose or duration, reserve hydrocodone/APAP for patients for whom alternative analgesics (e.g., non-opioid options) have not been tolerated or are not expected to provide adequate analgesia.

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How it works

Hydrocodone is a full mu-opioid receptor agonist producing analgesia and dose-related respiratory depression by reducing brain-stem responsiveness to carbon dioxide. There is no ceiling effect for analgesia; adverse effects—including sedation and respiratory depression—often limit dosing before maximum pain relief is reached. Acetaminophen in combination products adds non-opioid analgesia through central mechanisms; it does not reverse opioid respiratory depression but adds separate hepatotoxicity risk when cumulative APAP exceeds labeling limits.

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Dosing overview

Use the lowest effective dosage for the shortest duration consistent with treatment goals. Respiratory depression can occur at any time during therapy, especially during initiation or after dose increases. Institutional protocols and product formulations may vary—always verify the specific strength ordered.

5 mg / 325 mg or 2.5 mg / 325 mg
1–2 tabs q4–6h PRN
Initiate 1 to 2 tablets every 4 to 6 hours as needed; max 8 tablets/day per reviewed hydrocodone/APAP labeling
7.5 mg / 325 mg or 10 mg / 325 mg
1 tab q4–6h PRN
Initiate 1 tablet every 4 to 6 hours as needed; max 6 tablets/day per reviewed labeling
Pediatrics
Not established
Safety and effectiveness in pediatric patients have not been established in reviewed prescribing information
Combination APAP ceiling
Track total APAP
Labeling warns that acetaminophen liver injury often involves doses exceeding 4,000 mg/day from more than one APAP-containing product

Missed dose: Take the next dose at the usual time; do not double doses. Medication Guide instructs patients not to take more than prescribed and to call the prescriber if pain is not controlled.

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Onset, peak, duration, and half-life

ParameterValueNursing relevance
Hydrocodone peak (oral)~1.3 hours (mean after 10 mg dose in labeling PK data)Reassess sedation and respiratory rate within the first few hours after a new dose or strength change
Hydrocodone half-life~3.8 hours (mean in labeling PK data)Effects may persist through overlapping PRN intervals—count cumulative doses before approving another
Acetaminophen half-life1.25–3 hours (may increase with liver injury)Separate APAP toxicity timeline from opioid sedation when both components are involved in overdose
MetabolismCYP3A4 (primary) and CYP2D6 pathwaysCYP3A4 inhibitors may increase hydrocodone levels and prolong respiratory depression—notify prescriber/pharmacist

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Before you give it — Safety check

Pretreatment checks

  • Confirm indication, ordered strength (hydrocodone/APAP ratio), route, and interval; reconcile all other opioids and APAP sources on the MAR
  • Review baseline respiratory status, history of COPD, sleep apnea, obesity hypoventilation, and concurrent CNS depressants (midazolam, diazepam, other opioids, alcohol)
  • Perform medication reconciliation and verify cumulative 24-hour tablet count against labeling maximums for the ordered strength

Contraindications

  • Significant respiratory depression
  • Acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment
  • Known or suspected gastrointestinal obstruction, including paralytic ileus
  • Hypersensitivity to hydrocodone or acetaminophen (e.g., anaphylaxis)

Major interactions — verify before administration

Interacting drug / class Effect Nursing action
Benzodiazepines and other CNS depressants Profound sedation, respiratory depression, coma, death Hold and clarify unless prescriber documents lowest effective concurrent plan; ensure naloxone access per labeling
CYP3A4 inhibitors (e.g., macrolides, azole antifungals, protease inhibitors) Increased hydrocodone plasma concentration; prolonged opioid adverse reactions Monitor closely for sedation and respiratory depression; notify prescriber/pharmacist when new inhibitor starts
Mixed agonist/antagonists or partial agonists (e.g., buprenorphine) Reduced analgesia and/or precipitated withdrawal Do not co-administer without prescriber/pharmacy guidance; verify opioid rotation orders

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Administration

Route: Oral tablet (hydrocodone bitartrate and acetaminophen). Swallow whole with water; do not crush or chew unless a specific alternate formulation is ordered and pharmacy confirms safety.

  • Verify tablet strength and count tablets administered against the daily maximum for that strength per prescribing information
  • Confirm PRN interval (typically every 4 to 6 hours as needed) and time of last opioid dose before giving another
  • Assess pain with a validated tool (pain assessment) alongside sedation and respiratory status—not pain score alone
⚠️ Schedule II controlled substance

Hydrocodone is a Schedule II opioid with addiction, abuse, and misuse potential even at recommended doses. Store securely, follow controlled-substance documentation, and never administer based on patient or family requests alone without verifying the order and interval.

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Expected therapeutic response

  • Reduced pain intensity on reassessment without excessive sedation or respiratory depression
  • Patient remains arousable, maintains adequate respiratory rate and oxygen saturation for baseline risk profile
  • Functional goal met (e.g., deep breathing, ambulation) when pain was limiting activity—analgesia should enable safe movement, not unsafe somnolence
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Red flags — Stop and act

Escalate immediately when opioid toxicity or acetaminophen injury is suspected. Do not give another dose while these findings are unresolved unless prescriber directs a specific emergency plan.

  • Respiratory rate decline, shallow breathing, apnea, or SpO2 drop despite supplemental oxygen—support airway and initiate opioid antagonist protocol per facility policy
  • Marked somnolence, inability to arouse, or confusion with pinpoint pupils (or mydriasis if hypoxic)
  • Shortness of breath, chest tightness, or cyanosis after a dose—treat as respiratory emergency
  • Signs of APAP hepatotoxicity: nausea, vomiting, right upper quadrant pain, or jaundice—especially if total APAP from all sources may exceed 4,000 mg/day
  • Serious skin reaction, angioedema, or anaphylaxis—discontinue permanently and treat per emergency protocol
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Adverse effects

Adverse effectFrequency / severityNursing response
Respiratory depressionSerious; may be fatalStop opioid, support airway, administer naloxone per protocol, notify prescriber, continuous monitoring until spontaneous respiration is reliably re-established
Lightheadedness, dizziness, sedationMost frequently reported per labelingMonitor sedation and RR; hold additional doses if oversedated; fall precautions
Nausea and vomitingCommonSupportive care; protect airway if sedated; assess for opioid-induced ileus if severe
ConstipationCommon opioid effectProactive bowel regimen per prescriber; teach patients to report absence of bowel movement
Acetaminophen hepatotoxicitySerious with overdoseTrack cumulative APAP; notify prescriber for LFT trends; escalate if overdose suspected
Serotonin syndromeReported with serotonergic co-drugsHold and notify prescriber for hyperreflexia, agitation, autonomic instability, or tremor

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Overdose, toxicity, and antidote

Overdose may involve hydrocodone toxicity, acetaminophen toxicity, or both. Hydrocodone overdose presents with respiratory depression progressing to stupor or coma, skeletal muscle flaccidity, miosis (or mydriasis with hypoxia), bradycardia, hypotension, and death. Acetaminophen overdose may cause dose-dependent hepatic necrosis with delayed laboratory evidence.

Early signs

  • Increasing sedation, declining respiratory rate, hypoxemia on pulse oximetry
  • After APAP excess: nausea, vomiting, diaphoresis, malaise—hepatic injury may not appear for 48–72 hours per labeling

Antidote

Opioid antagonists such as naloxone are specific antidotes for clinically significant hydrocodone respiratory depression per reviewed prescribing information. Titrate to restore adequate ventilation; repeat doses may be needed because antagonist duration may be shorter than hydrocodone action. For acetaminophen component overdose, N-acetylcysteine (NAC) is the antidote when hepatic injury is suspected—follow toxicology and product labeling.

📞Poison control

Contact local poison control or medical toxicology services for overdose guidance per facility protocol and local emergency guidance. Maintain airway and ventilation while awaiting specialist input.

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Look-alike / sound-alike and error prevention

  • Hydrocodone vs morphine vs oxycodone—verify generic name and strength on label and MAR; potency and tablet count differ
  • 5/325 vs 10/325 vs 7.5/325—strength mix-ups change both opioid and APAP exposure; read both numbers every time
  • Combination vs single-entity products—duplicate APAP from “pain pills” plus standalone acetaminophen is a common overdose pathway
  • Hydrocodone vs hydromorphone—sound-alike names with very different potency; independent double-check high-alert orders
  • PRN interval errors—giving early doses before prior peak effect increases respiratory depression risk
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Practical bedside notes

TopicBedside guidance
Before first inpatient doseConfirm opioid tolerance, home opioid use, sleep apnea/COPD history, and whether benzodiazepines are active on the MAR.
APAP mathMultiply tablets given × 325 mg APAP per tablet; add IV/PO acetaminophen and other combination products before approving another dose.
Night shiftRespiratory depression risk rises when patients sleep unobserved—follow institutional sleep monitoring protocol after opioid doses.
Discharge teachingDiscuss secure storage, no sharing, and naloxone access when risk factors exist per labeling.
Commonly missedPRN hydrocodone/APAP still ordered after transition to another opioid—reconcile and discontinue duplicates.
Ask pharmacy whenNew CYP3A4 inhibitor starts, unclear tablet maximum, or patient reports worsening pain despite escalating doses (consider hyperalgesia).

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High-risk populations

Population Considerations
Elderly, cachectic, or debilitated Increased sensitivity to respiratory depression; start at low end of dosing range and titrate slowly with frequent reassessment per labeling.
Chronic pulmonary disease / sleep apnea Decreased respiratory reserve; even therapeutic doses may cause hypoxemia—enhanced monitoring and lower initial doses.
Renal or hepatic impairment Higher plasma hydrocodone concentrations may occur; use low initial dose and monitor for sedation and respiratory depression. APAP hepatotoxicity risk rises with liver disease and alcohol use.
Pregnancy Pregnancy Category C; extended use during pregnancy can cause neonatal opioid withdrawal syndrome (NOWS)—ensure neonatology availability if extended use is required. Not recommended during or immediately before labor when other techniques are appropriate per labeling.
Lactation Hydrocodone is present in human milk; monitor breastfed infants for excess sedation and respiratory depression. Withdrawal can occur in infants when maternal opioid is stopped or breastfeeding ceases.

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Monitoring and documentation

Monitor

  • Respiratory rate, depth, and pattern; sedation level; blood pressure and heart rate per protocol
  • SpO2 when pulmonary disease, sleep apnea, or concurrent CNS depressants are present
  • Pain scores alongside ventilation—adequate analgesia with inadequate breathing is an unsafe outcome
  • Cumulative tablet count and total daily acetaminophen from all sources; liver function tests when hepatotoxicity is suspected

Document

  • Strength (hydrocodone/APAP), number of tablets, route, time, indication, and pre/post respiratory-sedation assessment
  • PRN effectiveness, time of last dose, and prescriber notification when maximum daily tablets approached or exceeded
  • Patient education on sedation, breathing difficulty, constipation, and secure storage/disposal
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Patient teaching

  • Take exactly as prescribed—do not increase dose or frequency; serious breathing problems can occur even at prescribed doses
  • Do not combine with alcohol, benzodiazepines, or other sedating medicines unless the prescriber approves—risk of fatal respiratory depression
  • Do not use any other product containing acetaminophen; ask the pharmacist to identify APAP on labels
  • Report unusual sleepiness, slow or shallow breathing, difficulty waking, severe constipation, or allergic symptoms immediately
  • Store tablets securely out of reach of others; dispose of unused medication promptly per local take-back or labeling guidance; discuss naloxone access when risk factors exist

The Hold Rule

Do not give and contact the prescriber/pharmacist when:

The Hold Rule — When to pause and clarify
  • Respiratory rate or depth below institutional parameters, SpO2 below ordered threshold, or patient difficult or impossible to arouse
  • Order would exceed maximum daily tablets for the prescribed strength (6 or 8 tablets/day per reviewed labeling depending on hydrocodone strength) or cumulative APAP may exceed 4,000 mg/day from all sources
  • Active significant respiratory depression, acute severe asthma without monitoring, suspected GI obstruction, or known hypersensitivity to components
  • New or increased benzodiazepine, muscle relaxant, or other CNS depressant without a documented safe concurrent opioid plan
  • Patient already received alternate opioid or sedative with overlapping effect and prescriber has not clarified whether hydrocodone should still be given

Hold parameters may vary by institutional protocol. Follow prescriber orders, pharmacy guidance, and facility policy.

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Clinical practice integration and workflow

Hydrocodone/APAP is a common postoperative and emergency-department opioid—yet it remains a Schedule II high-alert medication because respiratory depression, CNS depressant stacking, and hidden acetaminophen exposure cause preventable harm. Build every shift workflow around ventilation before analgesia.

1. Check-before-you-give protocol

  • Right patient, strength, tablet count, interval, and route—read both hydrocodone and APAP numbers
  • Right respiratory status—RR, SpO2, sedation level acceptable per policy
  • Right cumulative exposure—24-hour tablet total, other opioids, sedatives, and all APAP sources reconciled
  • Right risk mitigation—naloxone availability considered for high-risk patients per labeling

2. High-alert and safety badge

Schedule II opioid · respiratory depression risk

ISMP classifies opioids as high-alert medications. Combination products add acetaminophen overdose risk when nurses focus only on the opioid component.

3. Clinical workflow: hold and question rules

  • Hold when sedation score or RR crosses protocol thresholds—even if pain remains moderate
  • Question orders that combine hydrocodone/APAP with other APAP products or duplicate PRN opioids
  • Escalate when pain worsens despite appropriate dosing—consider hyperalgesia, incomplete analgesia, or new complication rather than automatic dose increase

4. Critical teach-back questions

  • “What other medicines contain acetaminophen that you must avoid?” Patient should name none beyond what prescriber approved or state they will check labels for APAP/acetaminophen.
  • “When should you seek emergency help for breathing or sleepiness?” Patient should describe slow/shallow breathing, trouble staying awake, or blue lips/skin and need for urgent help per local guidance.

5. Care coordination

Pharmacy: Verify strength, daily maximum tablets, CYP3A4 interactions, and cumulative APAP from all orders before first dose.

Prescriber / pain team: Reassess when PRN use is frequent, sedation exceeds analgesic benefit, or non-opioid options may replace opioids.

🧠 Quick mental checklist

  • How many hydrocodone/APAP tablets in the last 24 hours—and am I at the 6- or 8-tablet daily maximum for this strength?
  • What is the total acetaminophen from this drug plus any other APAP source today?
  • Are benzodiazepines, muscle relaxants, or other opioids active on the MAR right now?
  • Is RR acceptable and is the patient easily arousable before I give this dose?
  • Does this patient have naloxone access or household risk factors that require teaching?
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Hydrocodone NCLEX practice questions

Rehearse NCLEX-style clinical judgment practice for hydrocodone bitartrate and acetaminophen using a tabbed postoperative case (MAR, labs, vitals, nursing notes), then rotate priority action, respiratory cue recognition, deterioration trends, matrix urgency sorting, antagonist management, and antidote cloze—recognise cues → analyse → prioritise → act → evaluate outcomes tied to respiratory depression and combination APAP safety.

Select a tab to view MAR, labs, vitals, and nursing note details for this case.

Medication administration record
  • Hydrocodone/acetaminophen 5/325 mg PO q4h PRN moderate pain — 2 tablets at 0800 and 1 tablet at 1200
  • Acetaminophen 650 mg PO q6h PRN fever — 1 dose at 0900
  • Alprazolam 0.5 mg PO at bedtime — last given 2200 previous evening
  • 0900: patient reports pain 6/10; 1300: pain 5/10 after noon dose
Question 1 — Priority action

After reviewing the case tabs, what is the nurse’s best FIRST action at 1345?

Question 2 — Recognize cues

Which findings increase concern for hydrocodone-related respiratory depression in this patient? Select a tab to review MAR, labs, vitals, and nursing notes.

Select all that apply

Question 3 — Trend interpretation

Despite repositioning and encouragement to deep breathe, updated data at 1355 show:

Trend snapshot
RR 6, shallow respirations; SpO2 86% on room air
Patient responds only to sternal rub; snoring with apneic pauses noted
Hydrocodone/APAP 5/325 mg: 2 tabs at 0800, 1 tab at 1200; alprazolam last dose 2200 yesterday
Naloxone available on the unit per protocol

Select all that apply — which nursing actions are appropriate now?

Question 4 — Matrix judgment

For each finding, select the best nursing urgency category (one per row).

Finding Expected — document and continue monitoring Concerning — notify prescriber/pharmacist Requires immediate follow-up
90 min after 1 tab hydrocodone/APAP: RR 14, SpO2 95% RA, patient alert
RR 10, SpO2 92%, drowsy but arousable after second opioid dose in 4 hours
RR 6, SpO2 86%, unarousable except to painful stimulus
Third hydrocodone/APAP dose requested while separate acetaminophen 650 mg also given today

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Question 5 — Antagonist management

After hydrocodone/APAP, the patient develops RR 5/min, SpO2 84% on 4 L/min, and is minimally responsive. Bag-mask ventilation is started. What is the nurse’s best action?

Question 6 — Cloze

For acetaminophen component overdose with suspected hepatic injury, reviewed prescribing information recommends when impending or evolving liver injury is suspected, in addition to supportive care for any opioid toxicity.

Answer key & rationale

Frequently asked questions

What is the greatest nursing safety risk with hydrocodone?

Serious, life-threatening, or fatal respiratory depression may occur with hydrocodone bitartrate and acetaminophen tablets, especially during initiation or after a dose increase. Concomitant benzodiazepines or other CNS depressants can cause profound sedation, respiratory depression, coma, and death. Nurses must assess respiratory rate, sedation, and oxygenation before every dose and hold when ventilation is inadequate.

What are the maximum daily tablet limits in reviewed prescribing information?

For 5 mg/325 mg or 2.5 mg/325 mg strengths, initiate 1 to 2 tablets every 4 to 6 hours as needed with a maximum of 8 tablets per day. For 7.5 mg/325 mg or 10 mg/325 mg strengths, initiate 1 tablet every 4 to 6 hours as needed with a maximum of 6 tablets per day. Always track cumulative acetaminophen from all sources.

What antidote is used for hydrocodone respiratory depression?

Opioid antagonists such as naloxone are specific antidotes to respiratory depression from hydrocodone overdose per reviewed prescribing information. Monitor until spontaneous respiration is reliably re-established and repeat antagonist doses as directed because reversal duration may be shorter than hydrocodone action. For acetaminophen toxicity, N-acetylcysteine is used when hepatic injury is suspected.

When should a nurse hold hydrocodone and contact the prescriber or pharmacist?

Hold for significant respiratory depression, excessive sedation, order exceeding daily tablet maximum for the prescribed strength, cumulative acetaminophen approaching or exceeding 4,000 mg per day from all sources, gastrointestinal obstruction, hypersensitivity, or new CNS depressants without a safe concurrent plan.

Why must nurses track acetaminophen in hydrocodone combination products?

Each combination tablet contains 325 mg acetaminophen. Labeling warns that acute liver failure has occurred with acetaminophen doses exceeding 4,000 mg per day, often involving more than one acetaminophen-containing product. Nurses must reconcile all APAP sources including standalone acetaminophen and other combination opioids.

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References

  1. DailyMed — Hydrocodone Bitartrate and Acetaminophen Tablets USP (SpecGx LLC), revised November 2023
    https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=73c1059b-0c7d-42ef-9827-f018858fc447
  2. StatPearls / NCBI Bookshelf — Opioid analgesics (nursing-relevant pharmacology reference)
    https://www.ncbi.nlm.nih.gov/books/NBK501202/
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Review and transparency

This medication guide is written and reviewed using NurseOnShift editorial and clinical review standards.

Educational use only. This content does not replace clinical judgment, prescriber orders, pharmacist guidance, product labeling, or institutional protocols.