What is Humatin (Paromomycin Sulfate)?
Humatin is an oral aminoglycoside antibiotic (paromomycin sulfate) FDA-approved for treating intestinal amebiasis and as adjunctive therapy in hepatic coma. 1
Drug Description and Formulation
Paromomycin sulfate is a broad-spectrum antibiotic produced by Streptomyces riomosus var. paromomycinus. It is a water-soluble aminoglycoside with the molecular formula C23H45N5O14•xH2SO4 and molecular weight of 615.64 (base). 1
Each capsule contains 250 mg of paromomycin (as the sulfate salt) for oral administration. 1
FDA-Approved Indications
The drug has two primary FDA-approved uses 1:
- Intestinal amebiasis (both acute and chronic)
- Note: NOT effective for extraintestinal amebiasis
- Hepatic coma (as adjunctive therapy)
Mechanism and Clinical Use
Paromomycin functions as a luminal amebicide, meaning it works within the intestinal lumen to eliminate Entamoeba histolytica cysts. This is critical because even after treating acute amebic colitis or liver abscess with metronidazole or tinidazole, patients require a luminal agent to prevent relapse. 2
Standard Dosing for Amebiasis
For luminal eradication after acute treatment: 30 mg/kg per day orally in 3 divided doses (approximately 500 mg three times daily for adults) for 10 days. 2 This follows completion of metronidazole or tinidazole therapy for acute disease.
Contraindications
Paromomycin is contraindicated in 1:
- Previous hypersensitivity reactions to the drug
- Intestinal obstruction
Adverse Effects Profile
The drug is generally well-tolerated with predominantly gastrointestinal side effects 3:
- Most common: Diarrhea (13.8% of cases) and other GI symptoms
- These effects typically resolve after treatment completion or discontinuation
- Rare cases of bloody stools, skin rash, or elevated liver enzymes have been reported
- Important: HIV infection does not appear to increase adverse effect incidence 3
Off-Label Uses (Not FDA-Approved)
While not FDA-approved for these indications, paromomycin has demonstrated efficacy in:
Visceral Leishmaniasis
- Dosing: 11 mg/kg intramuscularly daily for 21 days showed 94.6% cure rates in India 4
- Higher doses (15 mg/kg for 28 days or 20 mg/kg for 21 days) achieved 80-81% efficacy in Sudan 5
- Licensed in India (2007) as an affordable VL treatment 6
Cutaneous Leishmaniasis
- Topical formulations: 15% paromomycin with 12% MBCL or 0.5% gentamicin cream 7
Other Parasitic Infections
- Cryptosporidiosis (immunocompromised): 500 mg three times daily for 14-28 days 8
- Dientamoeba fragilis: More effective than metronidazole (81.8% vs 65.4% eradication) 9
Key Clinical Pearls
- Paromomycin is poorly absorbed from the GI tract, making it ideal for intestinal infections but ineffective for systemic/extraintestinal disease
- Always use as part of combination therapy for amebiasis: nitroimidazole first for tissue invasion, then paromomycin for luminal cysts
- The drug should be used only for proven or strongly suspected susceptible infections to prevent resistance development 1
- For leishmaniasis treatment, combination therapy is preferred over monotherapy to prevent resistance emergence 6