Hydrocodone and Homatropine

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Syrup, Oral:

Hydromet: Hydrocodone bitartrate 5 mg and homatropine methylbromide 1.5 mg per 5 mL (480 mL) [cherry flavor]

Generic: Hydrocodone bitartrate 5 mg and homatropine methylbromide 1.5 mg per 5 mL (473 mL)

Tablet, Oral:

Tussigon: Hydrocodone bitartrate 5 mg and homatropine methylbromide 1.5 mg [DSC]

Generic: Hydrocodone bitartrate 5 mg and homatropine methylbromide 1.5 mg

Pharmacology

Mechanism of Action

Hydrocodone: Binds to opiate receptors in the CNS, altering the perception of and response to pain; suppresses cough in medullary center; produces generalized CNS depression.

Homatropine: Anticholinergic agent; present in a subtherapeutic amount to discourage deliberate overdose.

Pharmacokinetics/Pharmacodynamics

Half-Life Elimination

Hydrocodone: ~4 hours

Use: Labeled Indications

Cough: Symptomatic relief of cough in adults.

Limitations of use: Reserve hydrocodone/homatropine for use in adult patients for whom the benefits of cough suppression outweigh the risks and who have had an adequate assessment of cough etiology.

Contraindications

Hypersensitivity to hydrocodone, homatropine, or any component of the formulation; children <6 years; significant respiratory depression; acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment; GI obstruction, including paralytic ileus (known or suspected).

Documentation of allergenic cross-reactivity for opioids or belladonna alkaloids is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Dosage and Administration

Dosing: Adult

Cough: Oral: Hydrocodone 5 mg/homatropine 1.5 mg (1 tablet or 5 mL) every 4 to 6 hours as needed (maximum: hydrocodone 30 mg/homatropine 9 mg [6 tablets or 30 mL] per 24 hours).

Discontinuation of therapy: For patients on long-term opioid therapy, reduce dose gradually by 25% to 50% every 2 to 4 days; consider dose increase to previous level if patient develops signs/symptoms of withdrawal, and then reduce dose more slowly by increasing the interval between dose reductions, decreasing amount of daily dose reduction, or both.

Dosing: Geriatric

Refer to adult dosing. Use with caution.

Dosing: Pediatric

Cough (antitussive):

Note: Due to risk of adverse effects (slowed or difficult breathing, misuse, abuse, addiction, overdose, and death), the FDA in January 2018 recommended against routine use of codeine/hydrocodone-containing cough/cold products for patients <18 years and that future manufacturer labeling for these products include a contraindication in this population (AAP 2018; FDA 2018a; FDA 2018b).

Manufacturer's labeling:

Tablet (Hydrocodone 5 mg and homatropine 1.5 mg per tablet):

Children 6 to 11 years: Oral: One-half (¹/₂) tablet every 4 to 6 hours as needed; maximum daily dose: 3 tablets/24 hours

Children ≥12 years and Adolescents: Oral: One tablet every 4 to 6 hours as needed; maximum daily dose: 6 tablets/24 hours

Syrup (Hydrocodone 5 mg and homatropine 1.5 mg per 5 mL):

Children 6 to 11 years: Oral: 2.5 mL every 4 to 6 hours as needed; maximum daily dose: 15 mL/24 hours

Children ≥12 years and Adolescents: Oral: 5 mL every 4 to 6 hours as needed; maximum daily dose: 30 mL/24 hours

Administration

Oral syrup: Use an accurate measuring device; a household teaspoon is not an accurate measuring device and could lead to overdosage.

Storage

Store at 20°C to 25°C (68°F to 77°F).

Drug Interactions

Acetylcholinesterase Inhibitors: May diminish the therapeutic effect of Anticholinergic Agents. Anticholinergic Agents may diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Monitor therapy

Aclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Alcohol (Ethyl): May enhance the CNS depressant effect of HYDROcodone. Alcohol (Ethyl) may increase the serum concentration of HYDROcodone. Management: Patients using the Zohydro ER brand of extended-release hydrocodone must not consume alcohol or alcohol-containing products due to possibly fatal outcomes. Other hydrocodone products are also expected to interact, but to a less significant degree. Avoid combination

Alizapride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Alvimopan: Opioid Agonists may enhance the adverse/toxic effect of Alvimopan. This is most notable for patients receiving long-term (i.e., more than 7 days) opiates prior to alvimopan initiation. Management: Alvimopan is contraindicated in patients receiving therapeutic doses of opioids for more than 7 consecutive days immediately prior to alvimopan initiation. Consider therapy modification

Amantadine: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy

Amphetamines: May enhance the analgesic effect of Opioid Agonists. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of other Anticholinergic Agents. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of Opioid Agonists. Specifically, the risk for constipation and urinary retention may be increased with this combination. Monitor therapy

Aprepitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification

Bosentan: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Botulinum Toxin-Containing Products: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromopride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromperidol: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Consider therapy modification

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Cimetropium: Anticholinergic Agents may enhance the anticholinergic effect of Cimetropium. Avoid combination

Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

CNS Depressants: May enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Conivaptan: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

CYP2D6 Inhibitors (Strong): May decrease serum concentrations of the active metabolite(s) of HYDROcodone. Specifically, concentrations of hydromorphone may be decreased. Monitor therapy

CYP3A4 Inducers (Moderate): May decrease the serum concentration of HYDROcodone. Monitor therapy

CYP3A4 Inducers (Strong): May decrease the serum concentration of HYDROcodone. Monitor therapy

CYP3A4 Inhibitors (Moderate): May increase the serum concentration of HYDROcodone. Monitor therapy

CYP3A4 Inhibitors (Strong): May increase the serum concentration of HYDROcodone. Monitor therapy

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Desmopressin: Opioid Agonists may enhance the adverse/toxic effect of Desmopressin. Monitor therapy

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Diuretics: Opioid Agonists may enhance the adverse/toxic effect of Diuretics. Opioid Agonists may diminish the therapeutic effect of Diuretics. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Consider therapy modification

Duvelisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Eluxadoline: Opioid Agonists may enhance the constipating effect of Eluxadoline. Avoid combination

Eluxadoline: Anticholinergic Agents may enhance the constipating effect of Eluxadoline. Avoid combination

Enzalutamide: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Concurrent use of enzalutamide with CYP3A4 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP3A4 substrate should be performed with caution and close monitoring. Consider therapy modification

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Erdafitinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification

Fosaprepitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fosnetupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Gastrointestinal Agents (Prokinetic): Anticholinergic Agents may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy

Gastrointestinal Agents (Prokinetic): Opioid Agonists may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy

Glucagon: Anticholinergic Agents may enhance the adverse/toxic effect of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Monitor therapy

Glycopyrrolate (Oral Inhalation): Anticholinergic Agents may enhance the anticholinergic effect of Glycopyrrolate (Oral Inhalation). Avoid combination

Glycopyrronium (Topical): May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Ipratropium (Oral Inhalation): May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Itopride: Anticholinergic Agents may diminish the therapeutic effect of Itopride. Monitor therapy

Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Larotrectinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Lemborexant: May enhance the CNS depressant effect of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Consider therapy modification

Levosulpiride: Anticholinergic Agents may diminish the therapeutic effect of Levosulpiride. Avoid combination

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy

Lorlatinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Avoid concurrent use of lorlatinib with any CYP3A4 substrates for which a minimal decrease in serum concentrations of the CYP3A4 substrate could lead to therapeutic failure and serious clinical consequences. Consider therapy modification

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

MiFEPRIStone: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Minimize doses of CYP3A4 substrates, and monitor for increased concentrations/toxicity, during and 2 weeks following treatment with mifepristone. Avoid cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus. Consider therapy modification

Minocycline (Systemic): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mirabegron: Anticholinergic Agents may enhance the adverse/toxic effect of Mirabegron. Monitor therapy

Mitotane: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Doses of CYP3A4 substrates may need to be adjusted substantially when used in patients being treated with mitotane. Consider therapy modification

Monoamine Oxidase Inhibitors: May enhance the adverse/toxic effect of HYDROcodone. Management: Consider alternatives to this combination when possible. Consider therapy modification

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Nalmefene: May diminish the therapeutic effect of Opioid Agonists. Management: Avoid the concomitant use of nalmefene and opioid agonists. Discontinue nalmefene 1 week prior to any anticipated use of opioid agonistss. If combined, larger doses of opioid agonists will likely be required. Consider therapy modification

Naltrexone: May diminish the therapeutic effect of Opioid Agonists. Management: Seek therapeutic alternatives to opioids. See full drug interaction monograph for detailed recommendations. Consider therapy modification

Netupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Nitroglycerin: Anticholinergic Agents may decrease the absorption of Nitroglycerin. Specifically, anticholinergic agents may decrease the dissolution of sublingual nitroglycerin tablets, possibly impairing or slowing nitroglycerin absorption. Monitor therapy

Ombitasvir, Paritaprevir, and Ritonavir: May increase the serum concentration of HYDROcodone. Management: Reduce the hydrocodone dose by 50% during concurrent use of ombitasvir, paritaprevir, and ritonavir; monitor closely for both analgesic effectiveness and for signs of toxicity or withdrawal. Consider therapy modification

Ombitasvir, Paritaprevir, Ritonavir, and Dasabuvir: May increase the serum concentration of HYDROcodone. Management: Reduce the hydrocodone dose by 50% during concurrent use of ombitasvir, paritaprevir, ritonavir, and dasabuvir; monitor closely for both analgesic effectiveness and for signs of toxicity or withdrawal. Consider therapy modification

Opioid Agonists: Anticholinergic Agents may enhance the adverse/toxic effect of Opioid Agonists. Specifically, the risk for constipation and urinary retention may be increased with this combination. Monitor therapy

Opioids (Mixed Agonist / Antagonist): May diminish the analgesic effect of Opioid Agonists. Management: Seek alternatives to mixed agonist/antagonist opioids in patients receiving pure opioid agonists, and monitor for symptoms of therapeutic failure/high dose requirements (or withdrawal in opioid-dependent patients) if patients receive these combinations. Avoid combination

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination

Oxatomide: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Palbociclib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Pegvisomant: Opioid Agonists may diminish the therapeutic effect of Pegvisomant. Monitor therapy

Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification

PHENobarbital: May enhance the CNS depressant effect of HYDROcodone. PHENobarbital may decrease the serum concentration of HYDROcodone. Management: Avoid use of hydrocodone and phenobarbital when possible. Monitor for respiratory depression/sedation. Because phenobarbital is also a strong CYP3A4 inducer, monitor for decreased hydrocodone efficacy and withdrawal if combined. Consider therapy modification

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy

Potassium Chloride: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Avoid combination

Potassium Citrate: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Citrate. Avoid combination

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

Pramlintide: May enhance the anticholinergic effect of Anticholinergic Agents. These effects are specific to the GI tract. Consider therapy modification

Primidone: May enhance the CNS depressant effect of HYDROcodone. Primidone may decrease the serum concentration of HYDROcodone. Management: Avoid use of hydrocodone and primidone when possible. Monitor for respiratory depression/sedation. Because primidone is also a strong CYP3A4 inducer, monitor for decreased hydrocodone efficacy and withdrawal if combined. Consider therapy modification

Ramosetron: Anticholinergic Agents may enhance the constipating effect of Ramosetron. Monitor therapy

Ramosetron: Opioid Agonists may enhance the constipating effect of Ramosetron. Monitor therapy

Revefenacin: Anticholinergic Agents may enhance the anticholinergic effect of Revefenacin. Avoid combination

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Secretin: Anticholinergic Agents may diminish the therapeutic effect of Secretin. Management: Avoid concomitant use of anticholinergic agents and secretin. Discontinue anticholinergic agents at least 5 half-lives prior to administration of secretin. Consider therapy modification

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Serotonergic Agents (High Risk): Opioid Agonists may enhance the serotonergic effect of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Sincalide: Drugs that Affect Gallbladder Function may diminish the therapeutic effect of Sincalide. Management: Consider discontinuing drugs that may affect gallbladder motility prior to the use of sincalide to stimulate gallbladder contraction. Consider therapy modification

Sodium Oxybate: May enhance the CNS depressant effect of CNS Depressants. Management: Consider alternatives to combined use. When combined use is needed, consider minimizing doses of one or more drugs. Use of sodium oxybate with alcohol or sedative hypnotics is contraindicated. Consider therapy modification

Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification

Succinylcholine: May enhance the bradycardic effect of Opioid Agonists. Monitor therapy

Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Consider therapy modification

Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Avoid concomitant use of tapentadol and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Thiazide and Thiazide-Like Diuretics: Anticholinergic Agents may increase the serum concentration of Thiazide and Thiazide-Like Diuretics. Monitor therapy

Tiotropium: Anticholinergic Agents may enhance the anticholinergic effect of Tiotropium. Avoid combination

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Umeclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Consider therapy modification

Test Interactions

Some quinolones may produce a false-positive urine screening result for opioids using commercially available immunoassay kits. This has been demonstrated most consistently for levofloxacin and ofloxacin, but other quinolones have shown cross-reactivity in certain assay kits. Confirmation of positive opioid screens by more specific methods should be considered.

Adverse Reactions

Frequency not defined.

Central nervous system: Anxiety, clouding of consciousness, dizziness, drowsiness, drug dependence (physical and psychological dependence with prolonged use), dysphoria, fear, lethargy, mental deficiency, mood changes, sedation

Dermatologic: Pruritus, skin rash

Gastrointestinal: Constipation, nausea, vomiting, xerostomia

Genitourinary: Urinary retention

Neuromuscular & skeletal: Genitourinary tract spasm

Respiratory: Respiratory depression

Warnings/Precautions

Concerns related to adverse effects:

• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).
• Hypotension: May cause severe hypotension (including orthostasis and syncope); risk is increased in patients with reduced blood volume or taking concurrent CNS depressants (eg, phenothiazines, general anesthetics). Avoid use in patients with circulatory shock.
• Phenanthrene hypersensitivity: Use with caution in patients with hypersensitivity reactions to other phenanthrene derivative opioid agonists (codeine, hydromorphone, levorphanol, morphine, oxycodone, oxymorphone).
• Respiratory depression: [US Boxed Warning]: Serious, life-threatening, or fatal respiratory depression may occur. Monitor closely for respiratory depression, especially during initiation or when used in patients at higher risk. Carbon dioxide retention from opioid-induced respiratory depression can exacerbate the sedating effects of opioids.

Disease-related concerns:

• Abdominal conditions: May obscure diagnosis or clinical course of patients with acute abdominal conditions. Use with caution in patients with underlying intestinal motility disorders; may result in constipation or obstructive bowel disease. Use is contraindicated with known or suspected obstruction, including paralytic ileus.
• Adrenocortical insufficiency: Use with caution in patients with adrenal insufficiency, including Addison disease. Long-term opioid use may cause secondary hypogonadism, which may lead to sexual dysfunction, infertility, mood disorders, and osteoporosis (Brennan 2013).
• Biliary tract impairment: Use with caution in patients with biliary tract dysfunction or acute pancreatitis; opioids may cause constriction of sphincter of Oddi and increase biliary tract pressure.
• Delirium tremens: Use with caution in patients with delirium tremens.
• Head trauma: Use with extreme caution in patients with head injury, intracranial lesions, or elevated intracranial pressure; exaggerated elevation of ICP may occur.
• Hepatic impairment: Use with caution in patients with severe hepatic impairment.
• Increased intraocular pressure/glaucoma: Use with caution in patients with increased intraocular pressure or glaucoma.
• Obesity: Use with caution in patients who are morbidly obese.
• Prostatic hyperplasia/urinary obstruction: Use with caution in patients with prostatic hyperplasia and/or urinary stricture.
• Psychosis: Use with caution in patients with toxic psychosis.
• Renal impairment: Use with caution in patients with severe renal impairment.
• Respiratory disease: Use with caution and monitor for respiratory depression in patients with significant chronic obstructive pulmonary disease or cor pulmonale and those having a substantially decreased respiratory reserve, hypoxia, hypercapnia, or preexisting respiratory depression, particularly when initiating therapy; critical respiratory depression may occur, even at therapeutic dosages. Avoid use in patients with acute febrile illness associated with productive cough or in patients with chronic respiratory disease unable to clear secretions. Use is contraindicated in patients with acute or severe bronchial asthma in an unmonitored setting or without resuscitative equipment.
• Seizure: Use with caution in patients with a history of seizure disorder; may cause or exacerbate preexisting seizures.
• Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.

Concurrent drug therapy issues:

• Alcohol: [US Boxed Warning]: Patients should not consume alcoholic beverages or use prescription or nonprescription products containing alcohol while taking hydrocodone/homatropine. The coingestion of alcohol may result in increased plasma levels and a potentially fatal overdose of hydrocodone.
• CYP 3A4 interactions: [US Boxed Warning]: Concomitant use of hydrocodone/homatropine with all CYP 3A4 inhibitors may result in an increase in hydrocodone plasma concentrations, which could increase or prolong adverse drug effects and may cause potentially fatal respiratory depression. In addition, discontinuation of a concomitantly used CYP 3A4 inducer may result in an increase in hydrocodone plasma concentration. Avoid use in patients taking a CYP 3A4 inhibitor or inducer. If concomitant use is necessary, monitor for signs and symptoms of toxicity or withdrawal.
• Benzodiazepines or other CNS depressants: [US Boxed Warning]: Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Avoid concomitant use in patients taking benzodiazepines, other CNS depressants, or alcohol.
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

• CYP2D6 "poor metabolizers": Due to the role of CYP2D6 in the metabolism of hydrocodone to hydromorphone (an active metabolite with higher binding affinity to mu-opioid receptors compared to hydrocodone), patients with genetic variations of CYP2D6, including "poor metabolizers" or "extensive metabolizers," may have decreased or increased hydromorphone formation, respectively. Variable effects in positive and negative opioid effects have been reported in these patients; however, limited data exists to determine if clinically significant differences of analgesia and toxicity can be predicted based on CYP2D6 phenotype (Hutchinson 2004; Otton 1993; Zhou 2009).
• Cachectic or debilitated patients: Use with caution in cachectic or debilitated patients; there is a greater potential for critical respiratory depression, even at therapeutic dosages.
• Elderly: Use with caution in the elderly; may be more sensitive to adverse effects.
• Neonates: Neonatal withdrawal syndrome: [US Boxed Warning]: Prolonged use of opioids during pregnancy can cause neonatal withdrawal syndrome, which may be life-threatening if not recognized and treated according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. Signs and symptoms include irritability, hyperactivity and abnormal sleep pattern, high-pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. Onset, duration, and severity depend on the drug used, duration of use, maternal dose, and rate of drug elimination by the newborn.
• Pediatric: Respiratory depression may occur even at therapeutic dosages; FDA and AAP recommend against use in pediatric patients <18 years due to risk of adverse effects (AAP 2018; FDA 2018a; FDA 2018b). Use with extreme caution in children.

Dosage form specific issues:

• Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity ("gasping syndrome") in neonates; the "gasping syndrome" consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer’s labeling.
• Oral solution: [US Boxed Warning]: Ensure accuracy when prescribing, dispensing, and administering hydrocodone/homatropine oral solution. Dosing errors can result in accidental overdose and death. Always use an accurate milliliter measuring device when measuring and administering. A household teaspoon is not an accurate measuring device and could lead to overdosage, which can result in serious adverse reactions.
• Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures and respiratory depression; use caution (AAP ["Inactive" 1997]; Zar 2007).

Other warnings/precautions:

• Addiction, abuse, and misuse: [US Boxed Warning]: Hydrocodone/homatropine exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Reserve for use in adult patients for whom the benefits of cough suppression are expected to outweigh the risks, and in whom an adequate assessment of the etiology of the cough has been made. Assess each patient's risk prior to prescribing and prescribe for the shortest duration consistent with individual patient treatment goals, monitor all patients regularly for the development of addiction or abuse, and refill only after reevaluation of the need for continued treatment. Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists; do not abruptly discontinue in a physically-dependent patient. Other risk factors associated with increased risk include a personal or family history of substance use disorder or mental illness (eg, major depression).
• Accidental ingestion: [US Boxed Warning]: Accidental ingestion of even one dose of hydrocodone/homatropine, especially in children, can result in a fatal overdose of hydrocodone.
• Cough: Appropriate use: Underlying cause of cough should be determined prior to prescribing and re-evaluated within 5 days for an unresponsive cough. Reserve for use in adult patients for whom benefits of cough suppression outweigh the risks and who have had an adequate assessment of cough etiology.

Monitoring Parameters

Relief of cough; signs/symptoms of addiction, abuse, or misuse; respiratory status; blood pressure (if clinically indicated)

Pregnancy

Pregnancy Considerations

[US Boxed Warning]: Prolonged use of opioids during pregnancy can cause neonatal withdrawal syndrome, which may be life-threatening if not recognized and treated according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.

Refer to individual monographs for additional information.

Patient Education

What is this drug used for?

• It is used to relieve coughing.
• Children:
• This drug is not for use in children younger than 18 years of age. The benefits of taking this drug for a cough due to allergies, a cold, or other infection do not outweigh the risks in children. If your child has been given this drug or if you have any questions, talk with your child's doctor.
• The use of hydrocodone in children younger than 6 years has led to deadly breathing problems. Talk with the doctor.

Frequently reported side effects of this drug

• Dry mouth
• Nausea
• Vomiting

Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:

• Severe dizziness
• Passing out
• Sexual dysfunction (males)
• No menstrual periods
• Decreased sex drive
• Trouble getting pregnant
• Chest pain
• Fast heartbeat
• Abnormal heartbeat
• Seizures
• Severe abdominal pain
• Severe headache
• Vision changes
• Severe fatigue
• Trouble breathing
• Slow breathing
• Shallow breathing
• Confusion
• Severe constipation
• Severe loss of strength and energy
• Trouble urinating
• Mood changes
• Pancreatitis like severe abdominal pain, severe back pain, severe nausea, or vomiting
• Adrenal gland problems like severe nausea, vomiting, severe dizziness, passing out, muscle weakness, severe fatigue, mood changes, lack of appetite, or weight loss
• Serotonin syndrome like dizziness, severe headache, agitation, sensing things that seem real but are not, fast heartbeat, abnormal heartbeat, flushing, tremors, sweating a lot, change in balance, severe nausea, or severe diarrhea
• Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.