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Drug Interaction Report

1 drug interaction and 19 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

metroNIDAZOLE loperamide

Applies to: metronidazole, loperamide

Using excessive doses of loperamide can cause serious and potentially fatal complications such as irregular heart rhythm and cardiac arrest, and the risk may be increased when combined with other medications that can also cause cardiac problems such as metroNIDAZOLE. You may also be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). Do not exceed the dose and frequency or duration of use of loperamide recommended on the product label or prescribed by your doctor. Talk to your doctor if you have any questions or concerns. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food/lifestyle interactions

Major food/lifestyle interactions

Major:

Food/Lifestyle metroNIDAZOLE

Applies to: metronidazole

Consumption of alcoholic beverages or products containing alcohol or propylene glycol during treatment with metroNIDAZOLE is not recommended. Doing so may occasionally trigger a reaction in some patients similar to the disulfiram reaction, which includes unpleasant effects such as flushing, throbbing in head and neck, throbbing headache, difficulty breathing, nausea, vomiting, sweating, thirst, chest pain, rapid heartbeat, palpitation, low blood pressure, dizziness, lightheadedness, blurred vision, and confusion. Rarely, more severe reactions may include abnormal heart rhythm, heart attack, heart failure, unconsciousness, convulsions, and even death. Patients treated with metroNIDAZOLE should continue to avoid using any products containing alcohol or propylene glycol for at least 3 days until after completion of therapy. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate food/lifestyle interactions

Moderate:

Food/Lifestyle loperamide

Applies to: loperamide

Alcohol can increase the nervous system side effects of loperamide such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with loperamide. Do not use more than the recommended dose of loperamide, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

Disease interactions

17 potential interactionsApplies to: 16 conditions, including High Blood Pressure, Heart Failure, Peripheral Neuropathy, Inflammatory Bowel Disease, and Hemodialysis.

Alcoholism

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Alcoholism.

Nitroimidazoles (e.g., metronidazole, tinidazole, fexinidazole, secnidazole) may inhibit alcohol dehydrogenase and occasionally precipitate a disulfiram-like reaction in patients who consume alcohol while being treated. Symptoms may include abdominal cramps, nausea, vomiting, headache, flushing, rash, weakness, diarrhea, abdominal pain, dizziness, sweating, and hypotension. Patients should be instructed to avoid alcohol-containing products during nitroimidazole therapy and for at least 48 hours (fexinidazole, secnidazole) to 72 hours (metronidazole, tinidazole) after the last dose. Therapy with nitroimidazoles should be administered cautiously in patients who might be prone to acute alcohol intake. An alternative therapy may be appropriate.

Bone Marrow Depression/Low Blood Counts

Major:

metronidazole

metroNIDAZOLE has a major potential interaction with Bone Marrow Depression/Low Blood Counts.

The use of nitroimidazoles (e.g., metronidazole, tinidazole) has rarely been associated with hematologic adverse effects such as mild, transient leukopenia, thrombocytopenia, and bone marrow aplasia. The manufacturers recommend that therapy with nitroimidazoles be administered cautiously in patients with evidence of or a history of blood dyscrasias, and that total and differential leukocyte counts be performed before and after treatment with these drugs, particularly in patients receiving repeated courses of therapy.

Central Nervous System Disorders

Major:

metronidazole

metroNIDAZOLE has a major potential interaction with Central Nervous System Disorders.

The use of nitroimidazoles (e.g., metronidazole, tinidazole) has been associated with the development of nervous system toxicity including convulsive seizures and dose-related peripheral neuropathy, the latter characterized primarily by numbness or paresthesia of an extremity. Persistent peripheral neuropathy has been reported in some patients treated for prolonged periods. Other neurologic adverse effects include vertigo, incoordination, ataxia, confusion, agitation, hallucinations, and depression. Therapy with nitroimidazoles should be administered cautiously in patients with or predisposed to seizures or other nervous system abnormalities. Nitroimidazole therapy should be discontinued promptly if neurologic disturbances occur.

Dehydration

Moderate:

loperamide

Loperamide has a moderate potential interaction with Dehydration.

Diarrhea can cause severe dehydration and electrolyte imbalance. Fluid accumulation within the GI track due to antiperistaltic-associated decrease in peristalsis can further aggravate dehydration and electrolyte imbalance. Antiperistaltic agents should be administered cautiously in patients with electrolyte imbalance and rehydration and electrolyte replacement should be initiated prior to initiation of therapy.

Fluid Retention

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Fluid Retention.

Flagyl I.V. RTU (brand of metronidazole ready-to-use injection) contains 14 mEq of sodium per each 500 mg dose of metronidazole. The sodium content should be considered when this product is used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

Heart Failure

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Heart Failure.

Flagyl I.V. RTU (brand of metronidazole ready-to-use injection) contains 14 mEq of sodium per each 500 mg dose of metronidazole. The sodium content should be considered when this product is used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

Hemodialysis

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Hemodialysis.

Metronidazole and its metabolites are moderately removed by hemodialysis. Doses should either be scheduled for administration after dialysis or supplemental doses be given after dialysis.

High Blood Pressure

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with High Blood Pressure.

Flagyl I.V. RTU (brand of metronidazole ready-to-use injection) contains 14 mEq of sodium per each 500 mg dose of metronidazole. The sodium content should be considered when this product is used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

History of Blood Dyscrasias

Major:

metronidazole

metroNIDAZOLE has a major potential interaction with History of Blood Dyscrasias.

The use of nitroimidazoles (e.g., metronidazole, tinidazole) has rarely been associated with hematologic adverse effects such as mild, transient leukopenia, thrombocytopenia, and bone marrow aplasia. The manufacturers recommend that therapy with nitroimidazoles be administered cautiously in patients with evidence of or a history of blood dyscrasias, and that total and differential leukocyte counts be performed before and after treatment with these drugs, particularly in patients receiving repeated courses of therapy.

Hypernatremia

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Hypernatremia.

Flagyl I.V. RTU (brand of metronidazole ready-to-use injection) contains 14 mEq of sodium per each 500 mg dose of metronidazole. The sodium content should be considered when this product is used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

Infectious Gastroenteritis

Major:

loperamide

Loperamide has a major potential interaction with Infectious Gastroenteritis.

The use of drugs with antiperistaltic activity (primarily antidiarrheal and antimuscarinic agents, but also antispasmodic agents such as dicyclomine or oxybutynin at high dosages) is contraindicated in patients with diarrhea due to pseudomembranous enterocolitis or enterotoxin-producing bacteria. These drugs may prolong and/or worsen diarrhea associated with organisms that invade the intestinal mucosa, such as toxigenic E. coli, Salmonella and Shigella, and pseudomembranous colitis due to broad-spectrum antibiotics. Other symptoms and complications such as fever, shedding of organisms and extraintestinal illness may also be increased or prolonged. In general, because antiperistaltic agents decrease gastrointestinal motility, they may delay the excretion of infective gastroenteric organisms or toxins and should be used cautiously in patients with any infectious diarrhea, particularly if accompanied by high fever or pus or blood in the stool. Some cough and cold and other combination products may occasionally include antimuscarinic agents for their drying effects and may, therefore, require careful selection when necessary.

Inflammatory Bowel Disease

Moderate:

loperamide

Loperamide has a moderate potential interaction with Inflammatory Bowel Disease.

Decreased intestinal motility and prolonged transit time have resulted in toxic megacolon in patients with acute ulcerative colitis. Paralytic ileus has also occurred. Antiperistaltic agent GI motility and prolongs transit time and therapy should be administered cautiously in these patients.

Liver Disease

Moderate:

loperamide

Loperamide has a moderate potential interaction with Liver Disease.

Therapy with antiperistaltic agents should be administered with extreme caution in patients with hepatorenal disease or abnormal liver enzymes. Antiperistaltic agents are metabolized by the liver (diphenoxylate to an active form) and primarily excreted in the feces. Hepatic coma can be precipitated.

Moderate:

metronidazole

metroNIDAZOLE has a moderate potential interaction with Liver Disease.

Metronidazole is extensively metabolized by the liver to both pharmacologically active and inactive compounds. The plasma clearance of metronidazole may be decreased and the half-life prolonged in patients with impaired hepatic function. Therapy with metronidazole should be administered cautiously at reduced dosages in patients with severe liver disease.

Noninfectious Colitis

Major:

metronidazole

metroNIDAZOLE has a major potential interaction with Noninfectious Colitis.

Clostridioides difficile-associated diarrhea (CDAD), formerly pseudomembranous colitis, has been reported with almost all antibacterial drugs and may range from mild diarrhea to fatal colitis. The most common culprits include clindamycin and lincomycin. Antibacterial therapy alters the normal flora of the colon, leading to overgrowth of C difficile, whose toxins A and B contribute to CDAD development. Morbidity and mortality are increased with hypertoxin-producing strains of C difficile; these infections can be resistant to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea after antibacterial use. Since CDAD has been reported to occur more than 2 months after antibacterial use, careful medical history is necessary. Therapy with broad-spectrum antibacterials and other agents with significant antibacterial activity should be administered cautiously in patients with history of gastrointestinal disease, particularly colitis; pseudomembranous colitis (generally characterized by severe, persistent diarrhea and severe abdominal cramps, and sometimes associated with the passage of blood and mucus), if it occurs, may be more severe in these patients and may be associated with flares in underlying disease activity. Antibacterial drugs not directed against C difficile may need to be stopped if CDAD is suspected or confirmed. Appropriate fluid and electrolyte management, protein supplementation, antibacterial treatment of C difficile, and surgical evaluation should be started as clinically indicated.

Peripheral Neuropathy

Major:

metronidazole

metroNIDAZOLE has a major potential interaction with Peripheral Neuropathy.

The use of nitroimidazoles (e.g., metronidazole, tinidazole) has been associated with the development of nervous system toxicity including convulsive seizures and dose-related peripheral neuropathy, the latter characterized primarily by numbness or paresthesia of an extremity. Persistent peripheral neuropathy has been reported in some patients treated for prolonged periods. Other neurologic adverse effects include vertigo, incoordination, ataxia, confusion, agitation, hallucinations, and depression. Therapy with nitroimidazoles should be administered cautiously in patients with or predisposed to seizures or other nervous system abnormalities. Nitroimidazole therapy should be discontinued promptly if neurologic disturbances occur.

Renal Dysfunction

Moderate:

loperamide

Loperamide has a moderate potential interaction with Renal Dysfunction.

Therapy with antiperistaltic agents should be administered with extreme caution in patients with hepatorenal disease or abnormal liver enzymes. Antiperistaltic agents are metabolized by the liver (diphenoxylate to an active form) and primarily excreted in the feces. Hepatic coma can be precipitated.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.