Usage
Flavoxate + Ofloxacin is prescribed for the treatment of urinary tract infections (UTIs) and associated symptoms like painful urination (dysuria), frequent urination, urgency, nocturia, suprapubic pain, and bladder spasms.
Pharmacological Classification:
- Flavoxate: Urinary antispasmodic, antimuscarinic agent.
- Ofloxacin: Fluoroquinolone antibiotic.
Mechanism of Action:
This combination drug works through a dual mechanism:
- Ofloxacin inhibits bacterial DNA gyrase and topoisomerase IV, essential enzymes for bacterial DNA replication and repair. This leads to bacterial cell death and clears the infection.
- Flavoxate relaxes the smooth muscles in the bladder and urinary tract by antagonizing the effects of acetylcholine, a neurotransmitter responsible for muscle contractions. This reduces bladder spasms and associated pain.
Alternate Names
While “Flavoxate + Ofloxacin” is the generic name, several brand names exist, including Zenflox-UTI and Flavoxite 0. There may be other international or regional variations.
How It Works
Pharmacodynamics: Ofloxacin exerts its bactericidal effect by inhibiting bacterial DNA replication. Flavoxate reduces urinary tract spasms by blocking the muscarinic receptors in the bladder smooth muscle, reducing the effect of acetylcholine.
Pharmacokinetics:
- Absorption: Both drugs are absorbed orally. Food may delay the absorption of ofloxacin, but does not significantly affect its overall bioavailability.
- Metabolism: Ofloxacin undergoes minimal hepatic metabolism. Flavoxate metabolism is not fully understood.
- Elimination: Primarily renal excretion for both drugs. Dose adjustments may be necessary in patients with renal impairment.
Mode of Action:
Ofloxacin inhibits bacterial topoisomerase II (DNA gyrase) and topoisomerase IV. Flavoxate competitively inhibits the effects of acetylcholine on smooth muscle muscarinic receptors in the bladder and urinary tract.
Receptor Binding, Enzyme Inhibition, or Neurotransmitter Modulation:
- Ofloxacin: Inhibits bacterial DNA gyrase and topoisomerase IV enzymes.
- Flavoxate: Muscarinic receptor antagonist.
Elimination Pathways: Primarily renal excretion for both Ofloxacin and Flavoxate.
Dosage
Standard Dosage
Adults:
One tablet containing Ofloxacin 200mg and Flavoxate 200mg twice daily. The duration of treatment typically ranges from 5 to 10 days, depending on the severity of the infection and clinical response. Administer orally with a full glass of water. May be taken with or without food; taking it with meals can help to reduce stomach upset.
Children:
Use in children under 18 years of age is generally not recommended due to limited safety and efficacy data. Pediatric dosing should be determined by a doctor if deemed necessary.
Special Cases:
- Elderly Patients: Dose adjustment may be required due to age-related decline in renal function.
- Patients with Renal Impairment: Dosage reduction is necessary based on creatinine clearance.
- Patients with Hepatic Dysfunction: Careful monitoring is recommended, although specific dose adjustments are not typically required.
- Patients with Comorbid Conditions: Caution is advised in patients with a history of seizures, cardiac conditions, or myasthenia gravis.
Clinical Use Cases
The primary clinical use case is the treatment of uncomplicated and complicated UTIs, including cystitis, pyelonephritis, and prostatitis. Dosage adjustments for specific clinical settings like intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations are not relevant for Flavoxate + Ofloxacin.
Dosage Adjustments
Dose adjustments are primarily based on renal function. Consult specific guidelines for recommendations based on creatinine clearance.
Side Effects
Common Side Effects:
Nausea, diarrhea, headache, dizziness, dry mouth, drowsiness, abdominal pain, vomiting.
Rare but Serious Side Effects:
Allergic reactions (rash, hives, itching, swelling), severe dizziness or fainting, tendonitis or tendon rupture, peripheral neuropathy (tingling or numbness in extremities), QT prolongation, cardiac arrhythmias, seizures, hallucinations, pseudomembranous colitis.
Long-Term Effects:
Long-term use of fluoroquinolones like ofloxacin is associated with a risk of tendinopathy and peripheral neuropathy.
Adverse Drug Reactions (ADR):
Severe allergic reactions, anaphylaxis, angioedema, Stevens-Johnson syndrome, toxic epidermal necrolysis, hepatotoxicity.
Contraindications
- Hypersensitivity to ofloxacin, flavoxate, or other quinolones.
- Myasthenia gravis.
- Gastrointestinal or genitourinary obstruction.
- Uncorrected hypokalaemia.
- Severe ulcerative colitis.
- Pregnancy (unless absolutely necessary).
Drug Interactions
- Antacids: Reduce ofloxacin absorption. Administer at least two hours apart.
- Warfarin and other anticoagulants: Ofloxacin can enhance anticoagulant effects. Monitor INR closely.
- Theophylline: Flavoxate can increase theophylline levels.
- Anticholinergics: Additive anticholinergic effects with flavoxate.
- Other QT-prolonging drugs: Increased risk of QT prolongation with ofloxacin.
- Corticosteroids: Increased risk of tendon rupture with ofloxacin.
Pregnancy and Breastfeeding
- Pregnancy: Ofloxacin is classified as Pregnancy Category C. It should be avoided during pregnancy unless the potential benefits outweigh the risks. Safer alternatives should be considered.
- Breastfeeding: Ofloxacin is excreted in breast milk. Potential adverse effects on the nursing infant include arthropathy. Breastfeeding should be discontinued or the drug avoided.
Drug Profile Summary
- Mechanism of Action: Ofloxacin inhibits bacterial DNA gyrase and topoisomerase IV. Flavoxate is a muscarinic receptor antagonist that relaxes the urinary tract muscles.
- Side Effects: Nausea, diarrhea, headache, dizziness, dry mouth, drowsiness; rarely: tendon rupture, peripheral neuropathy, seizures.
- Contraindications: Hypersensitivity to quinolones, myasthenia gravis, GI/GU obstruction.
- Drug Interactions: Antacids, warfarin, theophylline, anticholinergics.
- Pregnancy & Breastfeeding: Avoid if possible due to potential risks to the fetus/infant.
- Dosage: Adults: Ofloxacin 200 mg + Flavoxate 200 mg twice daily for 5-10 days.
- Monitoring Parameters: Renal function, signs of tendonitis, ECG in patients at risk of QT prolongation.
Popular Combinations
Flavoxate + Ofloxacin is itself a popular combination, exploiting the synergistic effect of antibiotic action with symptom relief. It is not commonly combined with other medications for the same indication.
Precautions
- Assess for allergies, renal/hepatic function, and history of seizures before initiating therapy.
- Monitor for tendon pain or swelling during and after treatment.
- Advise patients to avoid driving or operating machinery if dizziness occurs.
- Advise patients about the importance of completing the full course of treatment.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Flavoxate + Ofloxacin?
A: The standard adult dose is Ofloxacin 200 mg + Flavoxate 200 mg twice daily for 5-10 days. Dosage adjustments are required for renal impairment.
Q2: Can Flavoxate + Ofloxacin be used in children?
A: It is generally not recommended for children under 18 due to limited safety data.
Q3: What are the most common side effects?
A: Nausea, diarrhea, headache, dizziness, dry mouth, and drowsiness are common side effects.
Q4: What are the serious side effects to watch out for?
A: Tendon rupture, peripheral neuropathy, seizures, allergic reactions, and QT prolongation are rare but serious side effects.
Q5: Can this medication be taken during pregnancy or while breastfeeding?
A: It should be avoided during pregnancy and breastfeeding unless absolutely necessary, due to potential risks to the fetus/infant.
Q6: Are there any drug interactions I should be aware of?
A: Yes, interactions can occur with antacids, warfarin, theophylline, and other anticholinergic drugs. Inform patients about potential interactions with other medications they are taking.
Q7: How does Flavoxate + Ofloxacin work?
A: Ofloxacin is an antibiotic that kills bacteria causing UTIs, and flavoxate relaxes bladder muscles to relieve symptoms like spasms and pain.
Q8: What precautions should be taken before prescribing Flavoxate + Ofloxacin?
A: Assess renal function, screen for allergies to quinolones, and consider potential drug interactions. Caution is advised in patients with a history of seizures.
Q9: What should patients be advised about while taking this medication?
A: Patients should be advised to complete the full course of treatment, even if symptoms improve. They should also be aware of potential side effects and instructed to report any tendon pain, unusual neurological symptoms, or signs of an allergic reaction. Avoid driving or operating heavy machinery if dizziness or drowsiness occurs. Avoid excessive sun exposure.
