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Helidac Side Effects

Generic name: bismuth subsalicylate / metronidazole / tetracycline

Medically reviewed by Drugs.com. Last updated on Sep 12, 2024.

Note: This document provides detailed information about Helidac Side Effects associated with bismuth subsalicylate / metronidazole / tetracycline. Some dosage forms listed on this page may not apply specifically to the brand name Helidac.

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

Important warnings This medicine can cause some serious health issues

Oral route (kit)

Metronidazole has been shown to be carcinogenic in mice and rats.

It is unknown whether metronidazole is associated with carcinogenicity in humans.

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.

Do not use this medicine if you are also using methoxyflurane (Penthrane®) or have used disulfiram (Antabuse®) in the last 2 weeks. Do not drink alcohol and other products containing propylene glycol while you are using this medicine and for at least 3 days after your last dose.

If your condition does not improve or if it becomes worse, check with your doctor.

Using this medicine while you are pregnant, especially during the second and later part of a pregnancy, can harm your unborn baby. Birth control pills may not work as well to prevent pregnancy when used with this medicine. Use an effective form of birth control (eg, condoms, spermicide) to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.

Metronidazole may cause some people to become dizzy, clumsy, or trouble seeing clearly.

Children or teenagers who have or who are recovering from chickenpox or influenza should not use this medicines unless directed by the child's doctor. If nausea or vomiting occurs after using this medicine, check with the child's doctor right away.

Tetracycline may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking tetracycline:

You may still be more sensitive to sunlight or sunlamps for 2 weeks to several months or more after stopping tetracycline. If you have a severe reaction, check with your doctor.

Bismuth subsalicylate may cause your tongue to become a darker color or even black. It may also make your stools (bowel movements) black. This is only temporary and will not hurt you. Your tongue and stools will go back to normal when you stop using this medicine. Ask your doctor about this if you have any concerns.

Check with your doctor right away if you start to have a stiff neck, drowsiness, fever, severe headache, nausea, vomiting, painful eye movements, or eye sensitivity to light. These could be symptoms of a serious condition called aseptic meningitis.

Check with your doctor right away if you are having burning, numbness, tingling, or painful sensations in the arms, hands, legs, or feet. These could be symptoms of a condition called peripheral neuropathy.

This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. Avoid people who are sick. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.

Serious skin reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS) can occur with this medicine. Check with your doctor right away if you have black, tarry stools, blistering, peeling, or loosening of the skin, chest pain, chills, cough, diarrhea, fever, itching, joint or muscle pain, painful or difficult urination, red irritated eyes, red skin lesions, severe acne or skin rash, sore throat, sores or ulcers on the skin, swollen glands, unusual bleeding or bruising, or unusual tiredness or weakness while you are using this medicine.

This medicine may cause serious allergic reactions. Check with your doctor right away if you have feeling of warmth, itching, redness of the face, neck, arms and occasionally, upper chest, or redness of the skin.

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests (eg, x-rays).

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or non-prescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Helidac

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:

Less common side effects

  • black, tarry stools
  • body aches or pain
  • burning, itching, numbness, prickling, "pins and needles", or tingling feelings
  • burning upper stomach pain
  • chills
  • cough
  • difficulty in breathing
  • ear congestion
  • fever
  • headache
  • loss of appetite
  • loss of voice
  • nausea
  • pain or tenderness around the eyes and cheekbones
  • runny or stuffy nose
  • sneezing
  • sore throat
  • tightness in the chest
  • unusual tiredness or weakness
  • vomiting
  • vomiting of blood or material that looks like coffee grounds
  • weight loss

Rare side effects

  • bladder pain
  • bleeding from the rectum
  • bloody or cloudy urine
  • blurred vision
  • bruising
  • burning, dry, or itching eyes
  • chest pain or discomfort
  • confusion
  • diarrhea
  • difficult, burning, or painful urination
  • discharge, excessive tearing
  • dizziness
  • fainting
  • frequent urge to urinate
  • general feeling of discomfort or illness
  • increased sensitivity of the skin to sunlight
  • itching, skin rash
  • joint pain
  • large, flat, blue or purplish patches in the skin
  • lower back or side pain
  • muscle aches and pains
  • nervousness
  • pain or discomfort in the arms, jaw, back, or neck
  • pounding in the ears
  • redness or other discoloration of the skin
  • redness, pain, swelling of the eye, eyelid, or inner lining of the eyelid
  • redness, swelling, or soreness of the tongue
  • severe constipation
  • severe numbness, especially on one side of the face or body
  • severe sunburn
  • shivering
  • slow or fast heartbeat
  • sore throat
  • stomach pain
  • sweating
  • tooth disorder
  • trouble sleeping
  • trouble swallowing
  • tumor
  • white patches in the mouth or on the tongue

Incidence not known

  • blistering, peeling, loosening of the skin
  • chest pain
  • clumsiness
  • decreased vision
  • joint or muscle pain
  • red irritated eyes
  • red skin lesions, often with a purple center
  • redness or soreness around fingernails or loosening of the fingernails
  • sores, ulcers, or white spots in the mouth or on the lips
  • swollen glands
  • unusual bleeding or bruising

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

Symptoms of overdose

Other side effects of Helidac

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 side effects

  • belching
  • bloating
  • burning or itching around the anus
  • change in or loss of taste
  • darkening of the tongue
  • excess air or gas in the stomach or bowels
  • feeling of fullness
  • heartburn
  • indigestion
  • lack or loss of strength
  • passing gas
  • stomach discomfort or upset

Rare side effects

  • blemishes on the skin
  • difficulty in moving
  • drowsiness
  • dry mouth
  • joint swelling or stiffness
  • pimples

For healthcare professionals

Applies to bismuth subsalicylate / metronidazole / tetracycline: oral kit.

General adverse events

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

Gastrointestinal

Metronidazole:

Tetracycline:

Nervous system

Metronidazole:

Tetracycline:

Other

Metronidazole:

Tetracycline:

Respiratory

Metronidazole:

Psychiatric

Metronidazole:

Metabolic

Metronidazole:

Tetracycline:

Dermatologic

Metronidazole:

Tetracycline:

Cardiovascular

Metronidazole:

Tetracycline:

Musculoskeletal

Metronidazole:

Tetracycline:

Genitourinary

Metronidazole:

Hepatic

Tetracycline:

Immunologic

Tetracycline:

Ocular

Metronidazole:

Oncologic

Hematologic

Metronidazole:

Tetracycline:

Renal

Metronidazole:

Tetracycline:

Hypersensitivity

Tetracycline:

See also:

References

1. (2022) "Product Information. Helidac (bismuth subsalicylate/metronidazole/TCN)." Prometheus Inc

Further information

Helidac side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.