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Helidac Side Effects

Generic Name: bismuth subsalicylate / metronidazole / tetracycline

Note: This document contains side effect information about bismuth subsalicylate / metronidazole / tetracycline. Some of the dosage forms listed on this page may not apply to the brand name Helidac.

For the Consumer

Applies to bismuth subsalicylate / metronidazole / tetracycline: oral capsule, oral tablet, oral tablet chewable

Along with its needed effects, bismuth subsalicylate / metronidazole / tetracycline may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking bismuth subsalicylate / metronidazole / tetracycline:

More common
  • Abdominal or stomach pain
  • bloody or black, tarry stools
  • diarrhea
  • nausea
Less common
  • Burning, prickling, or tingling sensations
  • dizziness
  • vomiting
Rare
  • Bloody vomit
  • convulsions (seizures)
  • fainting
  • heart attack
  • irritation of the mouth or tongue
  • joint pain and swelling
  • sensitivity of the skin to sunlight
  • skin rash
  • trouble with swallowing

Get emergency help immediately if any of the following symptoms of overdose occur while taking bismuth subsalicylate / metronidazole / tetracycline:

Symptoms of overdose
  • Clumsiness or unsteadiness
  • confusion
  • continuing ringing or buzzing in ears
  • fast heartbeat
  • fast or deep breathing
  • fever
  • pain, numbness, or tingling in the arms, legs, hands, or feet
  • unusual tiredness
  • vomiting

Some side effects of bismuth subsalicylate / metronidazole / tetracycline may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common or rare
  • Burning or itching around the anus
  • constipation
  • general feeling of discomfort or illness
  • loss of appetite
  • nervousness
  • trouble sleeping

For Healthcare Professionals

Applies to bismuth subsalicylate / metronidazole / tetracycline: oral kit

General

The most commonly reported side effects included nausea, abdominal pain, and diarrhea.[Ref]

Gastrointestinal

Very common (10% or more): Nausea (up to 12%)
Common (1% to 10%): Abdominal pain, anal discomfort, constipation, diarrhea, duodenal ulcer, dyspepsia, flatulence, gastrointestinal hemorrhage, melena, stool abnormality/darkening/black stools, tongue discoloration/darkening, vomiting
Frequency not reported: Dry mouth, dysphagia, eructation, gastrointestinal monilia, glossitis, intestinal obstruction, rectal hemorrhage, stomatitis, tooth disorder

Metronidazole:
Frequency not reported: Abdominal pain, constipation, candida overgrowth, diarrhea, dry mouth, furry tongue, glossitis, nausea, pancreatitis, stomatitis, vomiting

Tetracycline:
Frequency not reported: Anogenital region inflammatory lesions/inflammatory lesions with Candida overgrowth, black hairy tongue, diarrhea, dysphagia, enterocolitis, esophagitis, esophageal ulceration, glossitis, nausea, vomiting[Ref]

Nervous system

Common (1% to 10%): Dizziness, dysgeusia/taste perversion/metallic taste, headache, paresthesia
Frequency not reported: Cerebral ischemia, somnolence, syncope

Metronidazole:
Frequency not reported: Aseptic meningitis, ataxia, convulsive seizures, dizziness, dysarthria, encephalopathy, headache, incoordination, metallic taste, peripheral neuropathy, syncope, vertigo

Tetracycline:
Frequency not reported: Intracranial hypertension, pseudotumor cerebri[Ref]

Other

Common (1% to 10%): Asthenia, pain
Frequency not reported: Infection, malaise

Metronidazole:
Frequency not reported: Fever, weakness

Tetracycline:
Frequency not reported: Tinnitus[Ref]

Respiratory

Common (1% to 10%): Sinusitis, upper respiratory infection
Frequency not reported: Rhinitis

Metronidazole:
Frequency not reported: Nasal congestion[Ref]

Psychiatric

Common (1% to 10%): Insomnia
Frequency not reported: Nervousness

Metronidazole:
Frequency not reported: Confusion, decreased libido, depression, insomnia, irritability[Ref]

Metabolic

Common (1% to 10%): Anorexia

Metronidazole:
Frequency not reported: Anorexia

Tetracycline:
Frequency not reported: Anorexia[Ref]

Dermatologic

Frequency not reported: Acne, ecchymosis, photosensitivity reaction, pruritus, rash

Metronidazole:
Frequency not reported: Erythematous rash, pruritus, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria

Tetracycline:
Frequency not reported: Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome, erythema multiforme, exfoliative dermatitis, Henoch-Schonlein purpura, maculopapular/erythematous rash, nail discoloration, onycholysis, photosensitivity, Stevens-Johnson syndrome, systemic lupus erythematosus exacerbation, toxic epidermal necrolysis, urticaria[Ref]

Cardiovascular

Frequency not reported: Chest pain, hypertension, myocardial infarction

Metronidazole:
Frequency not reported: T-wave flattening, flushing

Tetracycline:
Frequency not reported: Pericarditis[Ref]

Musculoskeletal

Frequency not reported: Arthritis, rheumatoid arthritis, tendonitis

Metronidazole:
Frequency not reported: Joint pain

Tetracycline:
Frequency not reported: Myasthenic syndrome[Ref]

Hepatic

Frequency not reported: ALT increase, AST increase

Tetracycline:
Frequency not reported: Hepatotoxicity, liver failure[Ref]

Genitourinary

Frequency not reported: Urinary tract infection

Metronidazole:
Frequency not reported: Darkened urine, dyspareunia, dysuria, incontinence, proctitis, sense of pelvic pressure, vaginal/vulvar dryness[Ref]

Immunologic

Frequency not reported: Flu syndrome

Tetracycline:
Frequency not reported: Serum sickness-like reaction[Ref]

Ocular

Frequency not reported: Conjunctivitis

Metronidazole:
Frequency not reported: Optic neuropathy[Ref]

Oncologic

Frequency not reported: Neoplasm[Ref]

Hematologic

Metronidazole:
Frequency not reported: Reversible neutropenia/leukopenia, reversible thrombocytopenia

Tetracycline:
Frequency not reported: Eosinophilia, hemolytic anemia, neutropenia, thrombocytopenia, thrombocytopenic purpura

Renal

Metronidazole:
Frequency not reported: Cystitis

Tetracycline:
Frequency not reported: Increased blood urea nitrogen

Hypersensitivity

Tetracycline:
Frequency not reported: Anaphylaxis, angioedema[Ref]

References

1. "Product Information. Helidac (bismuth subsalicylate/metronidazole/TCN)." Prometheus Inc, San Diego, CA.

Some side effects of Helidac may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

More about Helidac (bismuth subsalicylate / metronidazole / tetracycline)

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Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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