GABBRORAL

Indications

• Amoebic dysentery
• Intestinal infections caused by susceptible bacteria
• Leishmaniasis
• Certain parasitic infections

Dosage

Children: Refer to the BNF for Children for appropriate paediatric dosing guidance.

Adults: Refer to the BNF for specific adult dosing information based on the condition being treated.

Mechanism of action

Paromomycin inhibits protein synthesis by binding to 16S ribosomal RNA within the bacterial ribosome. This binding occurs at the A site of the 30S subunit, disrupting the normal binding of transfer RNA (tRNA) and leading to the production of defective polypeptide chains. The accumulation of these defective proteins ultimately results in bacterial cell death.

Pharmacodynamics

Paromomycin exhibits a broad antibacterial spectrum, and its activity is comparable to that of neomycin. It is effective against various gram-positive and gram-negative bacteria, and its mode of action involves the inhibition of protein synthesis, thereby hindering bacterial growth and replication.

Pharmacokinetics

Paromomycin is not significantly absorbed from the gastrointestinal tract when administered orally, which makes it particularly useful for treating intestinal infections. The drug is primarily excreted unchanged in the feces. When given parenterally, it is distributed throughout the body tissues, with a variable half-life depending on the route of administration. Renal function may significantly impact its clearance, necessitating dosage adjustments in patients with impaired kidney function.

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Abdominal pain
• Ototoxicity
• Nephrotoxicity

Precautions

• Use with caution in patients with renal impairment
• Monitor renal function during therapy
• Assess for potential hearing loss

Pregnancy

Paromomycin should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus. Limited data on use in pregnancy is available.

Breast-feeding

Paromomycin is excreted in breast milk, caution should be exercised when administering to nursing mothers.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Formulations

• Oral tablets
• Oral solution
• Injection

Mechanism of action

Paromomycin inhibits protein synthesis by binding to 16S ribosomal RNA. Bacterial proteins are synthesized by ribosomal RNA complexes which are composed of 2 subunits, a large subunit (50s) and small (30s) subunit, which forms a 70s ribosomal subunit. tRNA binds to the top of this ribosomal structure. Paramomycin binds to the A site, which causes defective polypeptide chains to be produced. Continuous production of defective proteins eventually leads to bacterial death.

Pharmacodynamics

Paromomycin is a broad spectrum aminoglycoside antibiotic produced by <i>Streptomyces rimosus</i> var. paromomycinus. The in vitro and in vivo antibacterial action of paromomycin closely parallels that of neomycin.