Hydrocodone

What is this medication for?

• Antitussive of choice for harsh dry non-productive cough: collapsing trachea, chronic bronchitis, kennel cough (C-URI); oral analgesia (moderate pain, incl. APAP-combination in dogs); opioid-related stereotypies/lick granuloma (exogenous opioid substitution)
• Only the stereotypy/lick-granuloma substitution use (plain hydrocodone)

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Sedation, constipation (chronic), vomiting/stomach/intestinal upset (Common)

Worth a phone call to your veterinarian

• Masks the cough of progressing respiratory disease (The monitoring trap — suppressing the alarm)

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Respiratory depression with co-depressants (High-dose class risk)

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Narcotic hypersensitivity; MAOIs (selegiline, amitraz); toxin-diarrhea; APAP products in cats
• has or has had: Addison's/hypothyroid/renal insufficiency/head trauma/acute abdomen/geriatric; respiratory disease with increased secretions or nebulization (liquify-then-can't-clear problem)

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • MAOIs
  • CNS depressants (anesthetics, antihistamines, phenothiazines, barbiturates, tranquilizers)
  • Antitussive stacking (butorphanol, dextromethorphan)

Storage and handling

C-III (combination products) — records/security tier below C-II.

Good to know

• Dry-harness rule: hydrocodone belongs to harsh DRY non-productive coughs (tracheal collapse) — productive/wet coughs need the secretions moved, not silenced.
• The stereotypy substitution trick: acral lick granuloma as self-opiate behavior → pharmacologic replacement (same logic as naltrexone approaches, opposite direction).
• APAP-combination arithmetic in dogs: dose by the hydrocodone component, but the ceiling is acetaminophen's (≤15 mg/kg every 8 hours) — double-math dispensing check.