Flagyl Nursing Considerations

Flagyl Nursing Implications

Flagyl Nursing Pharmacology

Flagyl, a brand name of metronidazole, is an antibiotic used to treat a wide range of infections. This antibiotic is used for specific bacterial and parasitic illnesses. Flagyl functions by preventing the development of specific bacteria and parasites.

Viral infections will not be treated by it (such as common cold, or flu). There are some stomach/intestinal ulcers brought on by a bacteria called H.pylori that can be treated with metronidazole in combination with other drugs.

Indications of Flagyl

  • Parasitic Infections. Flagyl is used to treat parasitic infections including trichomonas vaginal infections, amebic liver abscess, Giardia infections of the small intestine, and amebic dysentery (colon infection causing bloody diarrhea), and carriers of trichomonas (both sexual partners) who do not exhibit symptoms of infection.
  • Bacterial Infections. Infection of the colon brought on by the bacterium C. difficile is also treated with Flagyl. Numerous routinely prescribed antibiotics can change the sort of bacteria that live in the colon. C. When the regular forms of bacteria in the colon are suppressed by ordinary antibiotics, difficile, an anaerobic bacterium, can invade the colon and cause infection. Due to this, the colon becomes inflamed (pseudomembranous colitis), which causes stomach pain and severe diarrhea. Flagyl is also used to treat abscesses in the liver, pelvis, abdomen, and brain brought on by anaerobic bacteria that are sensitive to it, either by themselves or in combination with other antibiotics. For the treatment of bacterial vaginosis, Flagyl vaginal gel is also prescribed.
  • Stomach or Intestinal Ulcer. In treating Helicobacter pylori (H. pylori), which can lead to stomach or intestinal ulcers, Flagyl is also frequently used in conjunction with other medications.

Mechanism of Actions of Flagyl

In an anaerobic setting, Flagyl acts in the following ways to combat microorganisms

potential mechanism: When Flagyl enters the body, it decreases by proteins that transport electrons inside cells. With this modification to the metronidazole molecule, a gradient in concentration is kept that encourages the drug’s intracellular distribution transport. It is likely that free radicals are created, which then react with biological components. Components that cause the bacteria to die. The majority of obligate anaerobes are susceptible to metronidazole’s activity, however, it lacks any action against obligatory aerobes or facultative anaerobes that is therapeutically meaningful.

Pharmacokinetics of Flagyl

  • Absorption. When a multiple-dose regimen of 500mg three times a day was supplied intravenously, steady-state concentrations were obtained in around 3 days, and peak concentration was measured at 26 mg/L16. When taken orally in tablet form, metronidazole is completely absorbed, exhibiting a bioavailability of greater than 90%.
  • The volume of distribution. Metronidazole is found in a variety of bodily fluids and is readily dissolved throughout the body5. They consist of the placenta, cerebrospinal fluid, breastmilk, bile, saliva, and saliva.16 Metronidazole’s steady-state volume distribution in adults ranges from 0.51 to 1.1 L/kg. It reaches plasma concentrations of 60 to 100 percent in a variety of organs, including the central nervous system, but is not found in significant amounts in the placental tissue.
  • Protein Binding. Less than 20% of metronidazole is linked to plasma proteins.
  • Metabolism. Flagyl is metabolized in the liver through the processes of hydroxylation, oxidation, and glucuronidation.
  • Route of elimination. 60 to 80 percent of metronidazole and its metabolites are excreted in the urine, while 6 to 15 percent are eliminated in the feces.
  • Half-life. Flagyl has an elimination half-life of 6 to 10 hours.
  • Clearance. Due to their reduced clearance, patients with liver impairment may need dose modifications.

Side Effects of Flagyl

Most medications might have undesirable side effects in addition to their beneficial ones, however, not everyone encounters them. Some of the side effects of Flagyl are listed below. As the body becomes used to the new medication, the negative effects frequently disappear completely. However, if any of the following persist or side effects start to bother the patient, they should seek medical counsel from their physician.

Notable side effects of Flagyl include:

  • depression, sleep issues, and irritability
  • headache, dizziness, and weakness;
  • nausea, vomiting, appetite loss, and abdominal pain;
  • constipation, diarrhea
  • unfavorable metallic flavor;
  • rash and itching
  • pain during intercourse, itching or discharge from the vagina;
  • mouth sores
  • swollen tongue

If the patient gets neurologic side effects (more common while taking Flagyl long-term), advise them to stop taking the medication and contact the doctor right once:

  • pain, tingly sensation, or numbness in the hands or feet;
  • visual issues, pain behind the eyes, and light flashes
  • weakness in the muscles, issues with coordination or speaking;
  • difficulty understanding what is being said to or speaking;
  • seizure
  • stiff neck, fever, and heightened light sensitivity.

Get immediate medical attention if the patient experience any of the following symptoms of an allergic response to Flagyl:

  • hives
  • itching
  • warmth or tingling
  • fever
  • joint pain
  • dry mouth
  • dry vagina
  • stuffy nose
  • difficulty breathing
  • swelling in the face or throat
  • burning eyes
  • skin pain
  • skin rashes that blister and peel

Adverse Reactions to Flagyl

During metronidazole treatment, the following reactions have been documented:

  • Central Nervous System. The most severe adverse responses experienced by patients

receiving treatment with metronidazole are convulsive seizures, encephalopathy, aseptic meningitis, optic and peripheral neuropathy, which is primarily characterized by numbness or pain, and paresthesia in a body part. Moreover, patients also have mentioned headaches, syncope, nausea, vertigo, and other symptoms of ataxia and confusion, irritability, depression, weakness, dysarthria, and sleeplessness.

  • Gastrointestinal. The most often reported adverse effects might be referred to as

the digestive system, particularly nausea, which is occasionally accompanied by headache, anorexia, vomiting, diarrhea, epigastric discomfort, cramping in the abdomen, and constipation. It’s not rare to get a strong, unpleasant metallic taste. tongue with fur, glossitis, and stomatitis has happened; they may be linked to a sudden overgrowth of Candida that might happen while receiving treatment.

  • Dermatologic. Pruritus, Erythematous rash.
  • Cardiovascular. Electrocardiographic traces may reveal a flattening of the T-wave.
  • Renal. Cystitis, polyuria, incontinence, dysuria, and a feeling of pressure in the pelvis.

Instances of darkened urine.

  • Hematologic. Occasionally, reversible neutropenia (leukopenia); thrombocytopenia.

Drug Interactions of Flagyl

  • Disulfiram. Disulfiram and Flagyl should not be combined. The results of doing so could be harmful to the body. Its use in conjunction with metronidazole can result in psychotic responses. Some symptoms include:
  • Confusion
  • Having hallucinations, or experiencing unreal sights or sounds
  • Having delusions (believing falsehoods)

If disulfiram has been consumed during the last two weeks, avoid taking Flagyl.

  • Lithium. Elevated levels of lithium are associated with an increase in adverse effects. If the patient takes these medications together, the doctor needs to keep an eye on the patient’s lithium levels.
  • Blood thinners. The risk of bleeding increases when taking Flagyl and blood thinners, and this is one of the side effects of warfarin and other blood thinners.
  • Busulfan. If at all possible, stay away from combining busulfan and metronidazole. If the patient takes these medications together, the doctor might monitor the patient’s busulfan levels more frequently.
  • Cimetidine. Combining cimetidine and Flagyl may raise the body’s level of the drug and enhance its negative effects.
  • Phenytoin or phenobarbital. The body’s level of metronidazole may drop if the patient takes one of these medications along with it. The metronidazole may not be able to treat the infection as a result.

Flagyl Nursing considerations

  • Examine the patient’s history of allergies. This product can include inactive components that could lead to allergic reactions or other issues.
  • Examine the patient’s medical history, particularly for: liver disease, kidney disease, specific blood disorders (low blood cell counts), and a rare genetic illness (Cockayne syndrome).
  • Give the patient the advice to abstain from alcohol and items containing propylene glycol while using this medicine and for a minimum of three days after it has worn off because they may induce severe stomach cramps, nausea, vomiting, headaches, and flushing.
  • Inform the patient that taking this medication could make them dizzy. Do not drive, operate machines, or perform any activity that requires alertness until they can do so safely.
  • Keep an eye out for seizures and contact the doctor right once if the patient starts to exhibit more or more of them.
  • Observe peripheral neuropathy symptoms (numbness, tingling). To record any neuropathic changes, perform objective testing such as nerve conduction, and monofilaments.
  • Observe any symptoms of a reaction similar to taking disulfiram, a toxic reaction occurring when this drug is taken with alcohol). The symptoms include a severe headache, trouble breathing, nausea, vomiting, sweating, thirst, palpitations, chest discomfort, hypotension, syncope, anxiety, confusion, fatigue, dizziness, and blurred vision. Inform the doctor if these symptoms right away.
  • Evaluate the presence of dizziness that may impair balance, walking, or another functional status. Inform the medical team about any balance issues and functional limits, and advise the patient’s family and caregivers to be cautious to prevent injuries from falls.
  • Watch out for any changes in the patient’s mental state, such as irritability, headaches, or disorientation. If the patient experience any of these symptoms, call the doctor right away.
  • Check the Intravenous injection site for any discomfort, bruising, and irritation. Inform the doctor of any sustained or severe injection site reactions.
  • To help stop the spread of infection, always wash hands properly and disinfect equipment. As necessary for particular patients, use general precautions or isolation techniques.
  • Give the patient the advice to only use this medication as prescribed by their doctor. Tell the patient not to take more of it, not to take it more frequently, and not to take it for longer than the doctor has prescribed.
  • Remind the patient to continue taking this medication for the entire course of treatment, even if they begin to feel better after a few days, to help the infection completely clear up. The infection can come back if they discontinue using this medication too soon.
  • Advise the patient that If they miss a dosage of this medication, take it as soon as they remember. To resume their regular dosing schedule, skip the missed dose if it is almost time for the next dose. Not two dosages at once.
  • Tell the patient to keep the medication at room temperature, in a closed container, free of heat, moisture, and bright light. Keep away from children’s reach and avoid freezing.
  • Remind the patient that consuming alcohol while taking this medication can result in abdominal discomfort, nausea, vomiting, headaches, face flushing, and/or redness. Elixirs, cough syrups, and tonics are a few more alcohol-containing treatments that could be problematic. After the patient stop taking Flagyl, these issues could persist for at least a day. Alcoholic beverages may also taste different as a result of this medication. While taking this medication and for a minimum of three days after discontinuing it, they shouldn’t consume alcohol or use other alcohol-containing medications.
  • The outcomes of some medical tests may be impacted by this medication. Tell the patient that before undergoing any medical testing, they should let their doctor know they are taking Flagyl.
  • Call the emergency hotline if the patient has overdosed and exhibits dangerous symptoms like fainting out or difficulty breathing. If not, immediately dial a poison control hotline. Overdose symptoms can include dizziness, nausea, and vomiting.
  • To ensure that the infection is treated successfully, it’s crucial to monitor the patient’s progress and suggest that they schedule routine doctor visits. The necessity for blood tests to check for side effects may arise.
  • Discuss with the patient the possibility that Flagyl could result in dry mouth, a disagreeable or strong metallic taste, and an alteration in taste perception. Encourage the patient to use sugar-free sweets or gum, melt pieces of ice in their mouth, or use a saliva substitute to temporarily relieve dry mouth. Tell them to consult their physician or dentist if their mouth feels dry for more than two weeks. The likelihood of dental diseases such as dental caries, gum disease, and fungal infections may rise if the mouth remains dry.

Nursing Care Plan for Patients on Metronidazole (Flagyl)

Possible Nursing Diagnosis for Flagyl

Nursing Assessment

Flagyl Nursing InterventionsRationale
Assess the patient for signs and symptoms of bacterial infection.To confirm the indication for administering metronidazole (Flagyl).
Assess if the patient has kidney disease, yeast infection, seizures, and bone marrow problems.Metronidazole (Flagyl) should be administered with caution for patients with kidney disease, yeast infection, seizures, and bone marrow problems as the drug may worsen the condition.
Check the patient’s allergy status.Previous allergic reactions to metronidazole (Flagyl) may render the patient unable to take them. Alternatives to metronidazole (Flagyl) should therefore be considered in case of allergy.
Assess if the patient is pregnant or lactating.Metronidazole (Flagyl) can be prescribed to a pregnant women as this drug is under pregnancy category B which means it does not impose known harm to humans. Flagyl must only be administered under the direction of the physician.
Perform a focused neurological assessment of the patient.Metronidazole (Flagyl) may cause adverse CNS effects such as ataxia, neuropathy, and encephalopathy.  
Assess the patient’s veins in preparation for administering Flagyl.To ensure that there is a viable venous access before metronidazole (Flagyl) is given.
Collect blood for a kidney function check.metronidazole (Flagyl) may cause adverse effects on the kidneys if not dosed properly.

Nursing Planning and Intervention

Flagyl Nursing InterventionsRationale
Administer intravenous metronidazole (Flagyl) via a peripheral or central venous line. If giving oral Flagyl, it is best to take it with meals.       To ensure optimal absorption and therapeutic action by metronidazole (Flagyl), as well as reduce possible side effects. Flagyl may cause upset stomach, so it is recommended to take it with food. However, the oral medication can be taken on an empty stomach as well.
Monitor the venous access after administration. Ask the patient to report any pain or discomfort during and after administration of the drug.To check for any infiltration or phlebitis around the IV site.  
Educate the patient about the action, indication, common side effects, and adverse reactions to note when taking metronidazole (Flagyl).To inform the patient on the basics of metronidazole (Flagyl).
Monitor the patient’s input and output and commence stool chart.metronidazole (Flagyl) may cause diarrhea. Early detection of diarrhea can help institute a bowel program and relieve them effectively.
Discourage alcohol intake when on metronidazole (Flagyl).Alcohol can increase the possible GI side effects of Flagyl, such as nausea and vomiting.
Inform the patient that metronidazole (Flagyl) may cause nausea and vomiting and this should be reported to any healthcare professional once noticed.To inform the patient of the possible side effect of Flagyl on the gastrointestinal system, and to be able to administer antiemetics as soon as the patient reports the symptom.

Nursing Evaluation

Flagyl Nursing InterventionsRationale
Ask the patient to repeat the information about metronidazole (Flagyl).To evaluate the effectiveness of health teaching on metronidazole (Flagyl).
Check for any signs of allergic reaction to Flagyl, such as shortness of breath, skin rash, or swelling.To ensure the patient’s safety after the initial dose of Flagyl and to be able to reverse anaphylaxis quickly.
Monitor the patient’s full blood count and kidney function.To ensure that the metronidazole (Flagyl) did not cause any anemia, leukopenia, or thrombocytopenia, as well as damage to the kidney function.  
Monitor the patient for any signs of bleeding such as bruising.To check for any adverse effect of Flagyl which is the risk for bleeding.

Nursing References

Ackley, B. J., Ladwig, G. B., Makic, M. B., Martinez-Kratz, M. R., & Zanotti, M. (2020). Nursing diagnoses handbook: An evidence-based guide to planning care. St. Louis, MO: Elsevier.  Buy on Amazon

Gulanick, M., & Myers, J. L. (2022). Nursing care plans: Diagnoses, interventions, & outcomes. St. Louis, MO: Elsevier. Buy on Amazon

Ignatavicius, D. D., Workman, M. L., Rebar, C. R., & Heimgartner, N. M. (2020). Medical-surgical nursing: Concepts for interprofessional collaborative care. St. Louis, MO: Elsevier.  Buy on Amazon

Silvestri, L. A. (2020). Saunders comprehensive review for the NCLEX-RN examination. St. Louis, MO: Elsevier.  Buy on Amazon


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Anna Curran. RN, BSN, PHN

Anna Curran. RN-BC, BSN, PHN, CMSRN I am a Critical Care ER nurse. I have been in this field for over 30 years. I also began teaching BSN and LVN students and found that by writing additional study guides helped their knowledge base, especially when it was time to take the NCLEX examinations.

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