Home Drug Guide Bismuth Subsalicylate, Metronidazole, Tetracycline Hydrochloride

Drug Guide

Generic Name

Bismuth Subsalicylate, Metronidazole, Tetracycline Hydrochloride

Brand Names Helidac

Classification

Therapeutic: Helidac is used for Helicobacter pylori eradication in combination therapy.

Pharmacological: Combination of antibacterial agents and bismuth compound.

FDA Approved Indications

Helidac is indicated for the eradication of Helicobacter pylori infection in adults.

Mechanism of Action

Bismuth subsalicylate exhibits antimicrobial activity and coats the gastric mucosa; metronidazole disrupts DNA synthesis in anaerobic bacteria; tetracycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit.

Dosage and Administration

Adult: Typically, the regimen involves taking multiple capsules or tablets over 10-14 days as prescribed.

Pediatric: Use in children is not standard; consult specific pediatric dosing guidelines.

Geriatric: Dose adjustments may be necessary due to renal or hepatic function, monitor accordingly.

Renal Impairment: Adjust dose as needed, especially for tetracycline and metronidazole.

Hepatic Impairment: Use with caution; monitor liver function.

Pharmacokinetics

Absorption: Absorbed from the gastrointestinal tract; bioavailability varies.

Distribution: Widely distributed in body tissues and fluids.

Metabolism: Metronidazole is metabolized in the liver; tetracycline is partially metabolized; bismuth compounds are poorly metabolized.

Excretion: Renal excretion; fecal excretion also occurs.

Half Life: Approximately 8-10 hours for metronidazole; variable for others.

Contraindications

Hypersensitivity to any component.
Use with caution in patients with renal or hepatic impairment.
History of hypersensitivity to salicylates.

Precautions

Monitor for allergic reactions, especially in patients with salicylate sensitivity.
Use cautiously in pregnant women and lactation; consult current guidelines.

Adverse Reactions - Common

Nausea or vomiting (Common)
Darkening of stool or tongue (bismuth) (Common)

Adverse Reactions - Serious

Allergic reactions including anaphylaxis (Rare)
Clostridioides difficile-associated diarrhea (Rare)
Hepatotoxicity (Very rare)

Drug-Drug Interactions

Warfarin (increased bleeding risk)
Methotrexate (increased toxicity)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Assess for allergy history, prior hepatic or renal impairment.

Diagnoses:

Risk for infection that is resistant to treatment

Implementation: Administer with food to minimize GI upset; complete full course.

Evaluation: Monitor for eradication of H. pylori, symptom relief, and adverse effects.

Patient/Family Teaching

Take medication exactly as prescribed.
Report any allergic reactions, severe diarrhea, or signs of liver problems.
Avoid alcohol during therapy and for at least 48 hours after completion.

Special Considerations

Black Box Warnings:

None specifically for this combination.

Genetic Factors: Metronidazole has known genetic resistance concerns in some strains.

Lab Test Interference: Bismuth can interfere with certain laboratory tests, including stool tests.

Overdose Management

Signs/Symptoms: Nausea, vomiting, ataxia, lethargy, seizure.

Treatment: Supportive care, activated charcoal if ingestion is recent, and symptomatic treatment. Dialysis may be considered for severe metronidazole overdose.

Storage and Handling

Storage: Store at room temperature, away from moisture and light.

Stability: Stable under proper storage conditions for the duration of the expiration date.