Paromomycin
Paromomycin sulfate
Also known as: Humatin · Gabbromicina · Gabbroral · Gabroral · Humagel · Kaman · Sinosid · aminosidin sulphate · aminosidine sulphate · catenulin sulphate · crestomycin sulphate · hydroxymycin sulphate · monomycin A sulphate · neomycin E sulphate · paucimycin sulphate
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 |
|---|---|---|---|---|---|
| Treatment of cryptosporidiosis | 125-165 mg/kg | PO | twice daily | 5 days | 🌎 NA |
| Treatment of cryptosporidiosis | 150 mg/kg | PO | once a day | 5 days | 🌎 NA |
- Treatment of cryptosporidiosis: Caution: nephrotoxicity.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Treatment of cryptosporidiosis | 125-165 mg/kg | PO | twice daily | 5 days | 🌎 NA |
| Treatment of cryptosporidiosis | 150 mg/kg | PO | once a day | 5 days | 🌎 NA |
| Treatment of cryptosporidiosis | 150 mg/kg | PO | q12-24hr | Until 1 week past clinical resolution of diarrhea | 🌎 NA |
- Treatment of cryptosporidiosis: Consider using an alternate treatment first (e.g., azithromycin) or paromomycin at an initially reduced dosage level.
- Treatment of cryptosporidiosis: Caution: nephrotoxicity.
- Treatment of cryptosporidiosis: If the cat is responding to the first 7 days of therapy and toxicity has not been noted.
Reptiles
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Treatment of cryptosporidiosis | 300-800 mg/kg | PO | q24-48h | 7-14 days or as needed | 🌎 NA |
Sheep
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Treatment of cryptosporidiosis in Camelids (crias) | 50 mg/kg | PO | once per day (assumed) | 5-10 days | 🌎 NA |
- Treatment of cryptosporidiosis in Camelids (crias): Dosing interval not specified in original source, assumed once per day by Plumb.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Paromomycin is an oral aminoglycoside antibiotic primarily utilized in veterinary medicine for its antiparasitic properties, specifically against Cryptosporidium spp. and Leishmania spp. Because it is structurally related to neomycin, it remains largely unabsorbed in the gastrointestinal tract when the mucosa is intact, allowing it to act locally on enteric pathogens.
Clinical Pearl: While effective for enteric protozoa, its use in cats is highly controversial due to reports of severe systemic toxicity (including acute kidney injury, ototoxicity, and blindness) even without obvious GI ulceration. Many clinicians prefer alternative therapies like azithromycin for felines.
Mechanism of action
Paromomycin binds to the 30S ribosomal subunit of susceptible organisms → causes misreading of mRNA → inhibits protein synthesis, leading to cell death. In protozoa such as Leishmania, it is believed to target the mitochondria and ribosomes, disrupting cellular respiration and protein synthesis.
Safety & warnings
Contraindications
- Known hypersensitivity to paromomycin
- Ileus or intestinal obstruction
- Gastrointestinal ulceration
- Presence of blood in the stool (indicates mucosal breakdown and risk of systemic absorption)
Adverse effects
- Nausea
- Vomiting
- Diarrhea
- Inappetence
- Nonsusceptible bacterial or fungal overgrowth
- Nephrotoxicity (if systemically absorbed)
- Ototoxicity (if systemically absorbed)
- Pancreatitis (if systemically absorbed)
- Blindness (reported in cats)
Precautions
Use with extreme caution in cats. Because of potential severe toxicity (renal dysfunction, ototoxicity, blindness), some clinicians recommend avoiding this drug entirely in felines.
Do not use in animals with blood in the stool, as this signals compromised intestinal integrity, allowing the drug to be absorbed systemically and causing severe nephrotoxicity, ototoxicity, or pancreatitis.
Use with caution in patients with any form of intestinal ulceration.
Drug interactions
Paromomycin may reduce digoxin absorption
Paromomycin may reduce methotrexate absorption
Monitoring
- Clinical efficacy (resolution of diarrhea, negative fecal tests)
- Gastrointestinal adverse effects
- Renal function (especially if used in cats or if GI ulceration is suspected)
Pharmacokinetics
Absorption
Very poorly absorbed when given orally in patients with an intact gastrointestinal tract.
Distribution
Acts locally within the gastrointestinal lumen. Systemic distribution is minimal unless the GI mucosa is ulcerated or compromised.
Metabolism
Not significantly metabolized.
Elimination
Excreted primarily unchanged in the feces.
Overdose
Because paromomycin is not absorbed orally, acute overdose adverse effects should be limited to gastrointestinal distress (nausea, vomiting, diarrhea) in patients with an intact GI system.
Chronic overdoses or administration in patients with compromised GI mucosa may lead to severe systemic toxicity, including nephrotoxicity, ototoxicity, and pancreatitis.
Available products
Formulations
- Oral capsules
Human-labeled
- Paromomycin Sulfate Oral Capsules: 250 mg (Humatin®, generic)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Paromomycin capsules should be stored at room temperature (15-30°C; 59-86°F) in tight containers.
Client information
- Unless otherwise instructed by your veterinarian, give this medication with food.
- Monitor the stool: If you notice blood in your pet's stool, stop the medication immediately and contact your veterinarian, as this can increase the risk of severe side effects.
- Watch closely for signs of kidney issues (such as changes in drinking or urination habits), hearing loss, or vision changes, especially in cats.
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.