Paregoric
Camphorated Tincture of Opium
Also known as: Camphorated Tincture of Opium
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Acute colitis | 0.06 mg/kg PO three times daily | PO | TID | — | 🌎 NA |
| Maldigestion; malabsorption; antidiarrheal | 0.05-0.06 mg/kg PO two to three times daily | PO | BID to TID | — | 🌎 NA |
| Antidiarrheal | 0.05-0.06 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Maldigestion, malabsorption, anti-diarrheal | 0.05-0.06 mg/kg PO two to three times daily | PO | BID to TID | — | 🌎 NA |
- Maldigestion, malabsorption, anti-diarrheal: Use is controversial; this species may react with excitatory behavior.
Horses
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Antidiarrheal | 15-30 mL PO (Foals); 15-60 mL PO (Adults) | PO | — | — | 🌎 NA |
- Antidiarrheal: May have a detrimental effect in acute/bacterial diarrhea by delaying microbe clearance.
Cattle
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Antidiarrheal | 15-30 mL PO | PO | — | — | 🌎 NA |
- Antidiarrheal: Dose for calves.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Paregoric is an opiate-based gastrointestinal motility modifier occasionally used for the symptomatic treatment of diarrhea in veterinary patients.
Key Clinical Points:
- Composition: Contains 2 mg of anhydrous morphine equivalent per 5 mL, along with anise oil, glycerin, benzoic acid, camphor, and alcohol.
- Regulatory Status: It is a Schedule III (C-III) controlled substance.
- Critical Warning: Do NOT confuse paregoric with opium tincture (tincture of opium). Opium tincture contains 50 mg of anhydrous morphine equivalent per 5 mL, making it 25 times more potent than paregoric. Fatal overdoses can occur if these are interchanged.
- Species Considerations: Its use in cats is highly controversial due to the risk of paradoxical CNS excitation. In horses and other animals with potentially infectious diarrhea, opiates can delay the clearance of pathogens and worsen the clinical picture.
Mechanism of action
Paregoric exerts its antidiarrheal effects primarily through the action of morphine on mu-opioid receptors in the gastrointestinal tract.
- Motility Inhibition: Binding to enteric opioid receptors decreases the release of acetylcholine → inhibits excessive GI propulsion and peristalsis, increasing intestinal transit time.
- Secretion Reduction: Decreases intestinal secretion induced by cholera toxin, prostaglandin E2, and calcium-mediated (non-cyclic AMP/GMP mediated) diarrheas.
- Absorption: Prolonged transit time allows for enhanced mucosal absorption of water and electrolytes, solidifying the stool.
Safety & warnings
Contraindications
- Known hypersensitivity to narcotic analgesics
- Patients receiving monoamine oxidase inhibitors (MAOIs)
- Diarrhea caused by toxic ingestion (until the toxin is eliminated from the GI tract)
Adverse effects
- Dogs: Constipation, bloat, sedation, paralytic ileus, toxic megacolon, pancreatitis, CNS effects
- Cats: Excitatory behavior (controversial use)
- Horses: Delayed clearance of GI microbes, prolonged febrile state
Precautions
Diagnostic Warning: Opiates may obscure the diagnosis or clinical course of acute abdominal conditions (e.g., colic).
- Hepatic Disease: Use with extreme caution in patients with hepatic encephalopathy; hepatic coma may result.
- Respiratory Disease: Use with extreme caution in patients suffering from respiratory disease or acute respiratory dysfunction (e.g., pulmonary edema secondary to smoke inhalation).
- General Cautions: Use cautiously in patients with hypothyroidism, severe renal insufficiency, adrenocortical insufficiency (Addison's disease), head injuries, increased intracranial pressure, and in geriatric or severely debilitated patients.
- Infectious Diarrhea: May enhance bacterial proliferation and delay pathogen clearance.
Drug interactions
May cause increased CNS or respiratory depression when used concurrently.
Contraindicated. Opiates should not be used for at least 14 days after receiving MAOIs due to the risk of severe, potentially fatal reactions.
Monitoring
- Clinical efficacy (resolution of diarrhea)
- Fluid and electrolyte status (especially in severe diarrhea)
- CNS effects (sedation in dogs, excitation in cats), particularly if using high dosages
Pharmacokinetics
Absorption
The morphine in paregoric is absorbed in a variable fashion from the GI tract.
Metabolism
Rapidly metabolized in the liver. Serum morphine levels are considerably less than when morphine is administered parenterally.
Overdose
Acute overdosage of opiate antidiarrheals can result in severe CNS, cardiovascular, gastrointestinal, or respiratory toxicity.
- Because opiates significantly reduce GI motility, absorption of the drug from the GI tract may be delayed and prolonged, leading to a sustained toxic effect.
- Treatment: Naloxone is the specific reversal agent and may be necessary to reverse opiate-induced respiratory depression and CNS effects. Supportive care is essential.
Available products
Formulations
- Oral liquid: 2 mg morphine equivalent per 5 mL (with 45% alcohol)
Human-labeled
- Paregoric (camphorated tincture of opium): 2 mg of morphine equiv. per 5 mL (45% alcohol) in 473 mL; generic; (Rx; C-III)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store in tight, light-resistant containers. Avoid exposure to excessive heat or direct exposure to sunlight.
Client information
- Monitor your pet closely: If diarrhea persists, or if your animal appears listless, overly sedated, or develops a high fever, contact your veterinarian immediately.
- Strict Dosing: Give this medication exactly as prescribed. Because it contains an opiate, overdosing can cause serious breathing problems and extreme sedation.
- Do not substitute: Never substitute this medication with other human anti-diarrheal products or other opiate tinctures without explicit veterinary approval.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.