Moxifloxacin Krka
Fluoroquinolone antibiotic — moxifloxacin 400 mg
Moxifloxacin Krka is a fluoroquinolone antibiotic containing the active substance moxifloxacin. It is prescribed for adults (18 years and older) to treat certain bacterial infections — including acute bacterial sinusitis, exacerbation of chronic bronchitis, community-acquired pneumonia, and mild to moderate pelvic inflammatory disease — when conventional antibiotics cannot be used or have failed. Due to serious safety concerns, moxifloxacin should be reserved as a last-resort treatment option.
Quick Facts
Key Takeaways
- Moxifloxacin Krka is a reserve antibiotic — only used when first-line antibiotics are ineffective or unsuitable.
- The standard dose is one 400 mg tablet once daily, taken with or without food.
- Fluoroquinolones carry FDA and EMA black box warnings for tendon rupture, peripheral neuropathy, and CNS effects that may be irreversible.
- Do not take with antacids, iron, or zinc supplements — separate doses by at least 6 hours.
- Contraindicated in pregnancy, breastfeeding, patients under 18, and those with QT prolongation or severe liver disease.
What Is Moxifloxacin Krka and What Is It Used For?
Moxifloxacin Krka contains the active substance moxifloxacin, which belongs to a group of antibiotics called fluoroquinolones. These antibiotics work by targeting two essential bacterial enzymes — DNA gyrase (topoisomerase II) and topoisomerase IV — which are critical for bacterial DNA replication, transcription, repair, and recombination. By inhibiting these enzymes, moxifloxacin causes rapid bacterial cell death, making it a bactericidal rather than merely bacteriostatic agent.
Moxifloxacin demonstrates broad-spectrum activity against Gram-positive bacteria (including Streptococcus pneumoniae and Staphylococcus aureus), Gram-negative bacteria (such as Haemophilus influenzae and Moraxella catarrhalis), atypical respiratory pathogens (including Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila), and certain anaerobic organisms. This broad coverage makes it particularly useful for mixed infections where multiple organism types are suspected.
Importantly, Moxifloxacin Krka is not a first-line antibiotic. According to guidelines from the European Medicines Agency (EMA) and the U.S. Food and Drug Administration (FDA), fluoroquinolones should be reserved for infections where no alternative treatment options exist. This restriction stems from the potential for serious, disabling, and potentially irreversible adverse effects associated with this drug class.
Approved Indications
Moxifloxacin Krka tablets (400 mg) are approved for adults aged 18 years and older for the following bacterial infections, but only when conventional antibiotics cannot be used or have proven ineffective:
- Acute bacterial sinusitis: Infection of the sinuses caused by susceptible bacteria, when the infection is sufficiently severe to warrant antibiotic treatment and first-line agents have failed.
- Acute exacerbation of chronic bronchitis: A sudden worsening of long-standing airway inflammation, characterised by increased sputum production, purulence, and worsening shortness of breath.
- Community-acquired pneumonia (non-severe): Lung infection acquired outside of a hospital setting. Moxifloxacin should not be used for severe or complicated pneumonia cases as initial therapy.
- Mild to moderate pelvic inflammatory disease (PID): Infection of the female upper reproductive tract, including fallopian tubes and uterine lining. Treatment of PID with moxifloxacin alone is insufficient — an additional antibiotic must be co-prescribed to ensure adequate coverage.
When initial treatment with intravenous moxifloxacin has shown improvement, oral Moxifloxacin Krka tablets may be prescribed as step-down therapy to complete the treatment course for community-acquired pneumonia and complicated skin and soft tissue infections. However, oral moxifloxacin tablets should never be used as initial therapy for skin or soft tissue infections.
What Should You Know Before Taking Moxifloxacin Krka?
Moxifloxacin carries significant safety warnings that both patients and healthcare providers must carefully consider before initiating treatment. The decision to prescribe this antibiotic should involve a thorough risk-benefit analysis, particularly given the availability of safer alternatives for most common infections. Your doctor should only prescribe Moxifloxacin Krka after confirming that first-line antibiotics are unsuitable for your specific condition.
Contraindications
Any of the following conditions apply to you. Contact your doctor immediately if you are uncertain.
- Allergy: You are allergic to moxifloxacin, any other fluoroquinolone antibiotic, or any of the inactive ingredients.
- Pregnancy or breastfeeding: Moxifloxacin is contraindicated during pregnancy and lactation.
- Age: You are younger than 18 years. Safety and efficacy have not been established in children and adolescents.
- Tendon history: You have previously experienced tendon disease or tendon problems related to any quinolone antibiotic.
- Cardiac conditions: You have congenital or documented QT prolongation, electrolyte imbalances (particularly low potassium or magnesium), very slow heart rate (bradycardia), heart failure, or a history of abnormal heart rhythms.
- QT-prolonging medications: You are currently taking other medications known to prolong the QT interval.
- Severe liver disease: You have liver enzyme (transaminase) levels exceeding 5 times the upper limit of normal.
Warnings and Precautions
Fluoroquinolone antibiotics, including moxifloxacin, are associated with disabling and potentially irreversible serious adverse reactions that may occur together. These include tendinitis and tendon rupture, peripheral neuropathy, and central nervous system effects. Discontinue immediately if any of these occur and avoid use in patients who have previously experienced these effects with any fluoroquinolone.
Speak with your doctor before taking Moxifloxacin Krka if any of the following apply to you:
- Heart conditions: Moxifloxacin can alter the electrical activity of your heart (QT prolongation). Women and elderly patients are at increased risk. If you take medications that lower potassium levels, discuss this with your doctor.
- Aortic aneurysm: If you have been diagnosed with an enlargement or bulging of a large blood vessel (aortic aneurysm or peripheral aneurysm), or have a family history of these conditions, or risk factors such as connective tissue disorders (Marfan syndrome, Ehlers-Danlos syndrome), high blood pressure, or atherosclerosis.
- Heart valve disorders: If you have leaking heart valves or a family history of congenital heart valve disease.
- Epilepsy or seizure disorders: Moxifloxacin may lower the seizure threshold.
- Mental health conditions: Fluoroquinolones can trigger psychiatric adverse events including depression, anxiety, psychosis, and in very rare cases, suicidal thoughts.
- Myasthenia gravis: Moxifloxacin can worsen muscle weakness. Contact your doctor immediately if symptoms deteriorate.
- Glucose-6-phosphate dehydrogenase (G6PD) deficiency: This rare hereditary condition may increase your risk of adverse reactions.
- Diabetes: Blood glucose levels may fluctuate during treatment. Monitor carefully.
During Treatment — When to Seek Immediate Medical Attention
Contact your doctor or seek emergency care immediately if you experience any of the following during treatment with Moxifloxacin Krka:
- Heart palpitations or irregular heartbeat — your doctor may need to perform an ECG.
- Severe allergic reaction (anaphylaxis) — chest tightness, dizziness, feeling faint, difficulty breathing. Can occur with the very first dose.
- Liver damage — sudden malaise, nausea, yellowing of eyes or skin, dark urine, itching, bleeding tendency. Moxifloxacin can cause acute, potentially fatal hepatotoxicity.
- Seizures — stop taking moxifloxacin and seek immediate medical help.
- Tendon pain or swelling — especially in the Achilles tendon, wrist, elbow, or shoulder. Risk increases with age over 60, organ transplant recipients, kidney problems, or concurrent corticosteroid use. Tendon damage may occur within 48 hours or months after treatment.
- Nerve damage (peripheral neuropathy) — pain, burning, tingling, numbness, or weakness in hands or feet. Stop immediately to prevent potentially permanent damage.
- Severe diarrhoea containing blood or mucus — may indicate Clostridioides difficile-associated colitis, a potentially life-threatening complication.
- Severe skin reactions — Stevens-Johnson syndrome, toxic epidermal necrolysis (widespread blistering), or DRESS syndrome (rash with fever and organ involvement).
- Sudden severe pain in abdomen, chest, or back — may indicate aortic aneurysm or dissection, a medical emergency.
Pregnancy and Breastfeeding
Do not take Moxifloxacin Krka if you are pregnant, think you may be pregnant, or are breastfeeding. Fluoroquinolones cross the placental barrier and are excreted in breast milk. Animal studies have shown potential risks to developing cartilage in offspring. If you become pregnant during treatment, contact your doctor immediately. Animal studies do not suggest impairment of fertility.
Driving and Operating Machinery
Moxifloxacin may cause dizziness, light-headedness, transient visual disturbances, or fainting. If you experience these effects, do not drive or operate machinery. You are responsible for assessing your own fitness to drive while taking this medication.
How Does Moxifloxacin Krka Interact with Other Drugs?
Drug interactions with moxifloxacin can be dangerous and in some cases life-threatening. The most critical interactions involve the heart's electrical system — moxifloxacin prolongs the QT interval, and combining it with other QT-prolonging medications dramatically increases the risk of serious cardiac arrhythmias, including torsades de pointes, a potentially fatal heart rhythm disorder.
Always inform your doctor, pharmacist, or other healthcare professional about all medications you are currently taking, have recently taken, or plan to take. This includes over-the-counter medicines, herbal supplements, and vitamin preparations.
Major Interactions — Do Not Combine
| Drug Category | Examples | Risk |
|---|---|---|
| Antiarrhythmics | Quinidine, amiodarone, sotalol, disopyramide, dofetilide, ibutilide | Additive QT prolongation — risk of fatal arrhythmia |
| Antipsychotics | Haloperidol, pimozide, sertindole, phenothiazines, sultopride | QT prolongation and torsades de pointes |
| Tricyclic antidepressants | Amitriptyline, nortriptyline, imipramine | QT prolongation |
| Certain antimicrobials | Sparfloxacin, IV erythromycin, pentamidine, halofantrine, saquinavir | QT prolongation |
| Certain antihistamines | Terfenadine, astemizole, mizolastine | QT prolongation |
| Other QT-prolonging agents | Cisapride, IV vincamine, bepridil, diphemanil | QT prolongation |
Absorption-Reducing Interactions
Certain medications significantly reduce the absorption of moxifloxacin from the gastrointestinal tract, rendering the antibiotic less effective or potentially ineffective. These products must be taken at least 6 hours before or after moxifloxacin:
- Antacids containing magnesium or aluminium
- Iron supplements and iron-containing multivitamins
- Zinc supplements
- Sucralfate (used for stomach ulcers)
- Didanosine (antiviral medication)
Oral activated charcoal taken simultaneously with moxifloxacin severely reduces its efficacy and these should never be taken concurrently.
Other Important Interactions
- Warfarin and other oral anticoagulants: Moxifloxacin may enhance anticoagulant effects. Your doctor may need to monitor your INR/coagulation time more frequently.
- Potassium-lowering drugs: Diuretics, laxatives (in high doses), corticosteroids, and amphotericin B can lower blood potassium, increasing the risk of dangerous heart rhythm disturbances.
- Corticosteroids: Concurrent use increases the risk of tendon inflammation and rupture, as well as aortic aneurysm.
The efficacy of Moxifloxacin Krka is not affected by food, including dairy products. You may take your tablet with or without meals.
What Is the Correct Dosage of Moxifloxacin Krka?
Always take Moxifloxacin Krka exactly as your doctor or pharmacist has instructed. Do not exceed the recommended dose, as higher doses increase the risk of cardiac side effects, particularly QT prolongation. The tablet should be swallowed whole (to avoid its extremely bitter taste) with a generous amount of water or other non-dairy liquid.
Adults
Standard Adult Dose
400 mg (one tablet) once daily, taken at approximately the same time each day. Can be taken with or without food. No dose adjustment required for low body weight or renal impairment.
| Indication | Duration | Notes |
|---|---|---|
| Acute bacterial sinusitis | 7 days | Only when first-line treatment has failed |
| Acute exacerbation of chronic bronchitis | 5–10 days | Reserve antibiotic use |
| Community-acquired pneumonia (non-severe) | 10 days | Oral only; not for severe CAP |
| Community-acquired pneumonia (IV to oral switch) | 7–14 days total | Most patients switch to oral within 4 days |
| Pelvic inflammatory disease (mild to moderate) | 14 days | Must be combined with another antibiotic |
| Skin and soft tissue infections (IV to oral switch) | 7–21 days total | Oral switch usually within 6 days; not for initial therapy |
Children and Adolescents
Moxifloxacin Krka is not approved for use in patients under 18 years of age. Safety and efficacy have not been established in this population. Fluoroquinolones may cause damage to developing cartilage in growing children and adolescents.
Elderly Patients
No dose adjustment is required for elderly patients. However, older adults (over 60 years) are at significantly increased risk of fluoroquinolone-associated tendon disorders, especially when corticosteroids are used concurrently. Elderly patients with kidney problems should ensure adequate hydration to prevent dehydration-related kidney injury.
Missed Dose
If you forget to take your tablet, take it as soon as you remember on the same day. If you do not remember until the next day, take your normal dose (one tablet) — do not take a double dose to make up for the missed one. If you are unsure what to do, contact your doctor or pharmacist.
Overdose
If you take more than the prescribed dose (more than one tablet per day), or if a child accidentally ingests this medication, contact your doctor, emergency department, or poison control centre immediately. Bring the remaining tablets or the packaging with you. Overdose data in humans is limited; single doses up to 1200 mg and multiple doses of 600 mg over 10 days have been tolerated in clinical trials, though QT prolongation risk increases with dose.
It is essential to complete the full prescribed course of treatment, even if you feel better after a few days. Stopping too early may result in incomplete eradication of the infection, recurrence, or development of antibiotic-resistant bacteria.
What Are the Side Effects of Moxifloxacin Krka?
Like all medicines, Moxifloxacin Krka can cause side effects, although not everyone experiences them. The fluoroquinolone class of antibiotics is associated with unique safety concerns that distinguish it from other antibiotic classes. Some adverse effects can be long-lasting (months to years), disabling, and potentially permanent — this is the primary reason why moxifloxacin should only be prescribed when no safer alternative exists.
Abnormally fast heartbeat; signs of liver damage (yellowing of skin/eyes, dark urine, severe nausea); severe skin reactions (blistering, peeling); tendon pain or swelling; nerve damage symptoms (burning, tingling, numbness in extremities); severe bloody diarrhoea; severe allergic reaction (difficulty breathing, swelling of face/throat); sudden severe abdominal/chest/back pain.
Common
- Nausea
- Diarrhoea
- Dizziness
- Headache
- Abdominal pain
- Vomiting
- Elevated liver enzymes (transaminases)
- Fungal superinfection (oral or vaginal candidiasis)
Uncommon
- Skin rash, itching, hives
- Taste disturbances
- Insomnia and sleep disturbances
- Constipation, flatulence, dyspepsia
- Vertigo, drowsiness, tremor
- Anxiety, restlessness, confusion
- Palpitations, irregular heartbeat, ECG changes
- Joint pain, muscle pain, back pain
- Decreased appetite, sweating
- Visual disturbances (blurred or double vision)
- Low white blood cell count
- Shortness of breath
- Chest pain, angina
- Dry skin, dehydration
Rare
- Tendinitis (tendon inflammation)
- Peripheral neuropathy (nerve damage in extremities)
- Seizures
- Depression (may lead to self-harm in very rare cases)
- Severe diarrhoea (antibiotic-associated colitis including pseudomembranous colitis)
- Anaphylactic reaction (severe allergy)
- Airway swelling
- Liver inflammation (hepatitis), jaundice
- Hallucinations, abnormal dreams
- Impaired kidney function
- Muscle cramps, muscle twitching
- Tinnitus (ringing in ears)
- High or low blood pressure
- Memory loss, concentration difficulties
- Hearing impairment (usually reversible)
- Altered sense of smell
Very Rare
- Tendon rupture (especially Achilles tendon)
- Fulminant hepatitis (potentially fatal liver failure)
- Torsades de pointes (life-threatening heart arrhythmia)
- Cardiac arrest
- Transient vision loss
- Psychosis
- Suicidal ideation
- Rhabdomyolysis (muscle breakdown)
- Stevens-Johnson syndrome, toxic epidermal necrolysis
- DRESS syndrome (drug reaction with eosinophilia and systemic symptoms)
- SIADH (syndrome of inappropriate antidiuretic hormone)
- Hypoglycaemic coma
- Vasculitis (inflammation of blood vessels)
- Agranulocytosis, pancytopenia
- Aortic aneurysm and dissection
In very rare cases, fluoroquinolone antibiotics have caused adverse effects lasting months to years or becoming permanent. These include tendon inflammation and rupture, joint pain, difficulty walking, abnormal sensations (tingling, burning, numbness), neuropathy, fatigue, memory impairment, sleep disorders, anxiety, depression, and impaired hearing, vision, taste, and smell. If you experience any of these, contact your doctor immediately before continuing treatment.
How Should You Store Moxifloxacin Krka?
Proper storage of Moxifloxacin Krka ensures the medication remains effective and safe throughout its shelf life. Incorrect storage may reduce the potency of the active ingredient or lead to degradation of the tablet coating.
- Keep out of sight and reach of children.
- Store in the original packaging to protect from moisture.
- No special temperature requirements — store at room temperature.
- Do not use after the expiry date (EXP) printed on the carton. The expiry date refers to the last day of the stated month.
- Disposal: Do not throw unused medicines in household waste or down the drain. Return unused medication to your pharmacy for proper disposal to protect the environment.
What Does Moxifloxacin Krka Contain?
Active Ingredient
Each film-coated tablet contains moxifloxacin hydrochloride, equivalent to 400 mg moxifloxacin.
Inactive Ingredients
Tablet core: Microcrystalline cellulose, croscarmellose sodium, magnesium stearate.
Film coating: Hypromellose 6 mPa·s, macrogol 4000, titanium dioxide (E171), red iron oxide (E172).
Appearance
The film-coated tablets are dark pink, biconvex, capsule-shaped, measuring approximately 15.9–16.6 mm in length and 5.8–7.0 mm in thickness. They are available in blister packs (OPA/Al/PVC-Al foil) containing 5, 7, 10, 14, 25, 28, 30, 50, 70, 80, 100, or 120 tablets. Not all pack sizes may be marketed.
This medicine contains less than 1 mmol (23 mg) sodium per tablet, which means it is essentially sodium-free. This is relevant for patients on a controlled sodium diet.
Frequently Asked Questions About Moxifloxacin Krka
Moxifloxacin Krka is a fluoroquinolone antibiotic used to treat bacterial sinusitis, acute exacerbation of chronic bronchitis, community-acquired pneumonia (non-severe cases), and mild to moderate pelvic inflammatory disease. It is strictly a reserve antibiotic, meaning it should only be used when first-line antibiotics have failed or are contraindicated. The oral tablet form (400 mg) is the most commonly prescribed version, though an intravenous infusion form is available for hospital use.
The most serious side effects include tendon inflammation and rupture (especially the Achilles tendon), peripheral neuropathy (nerve damage causing pain, burning, tingling, or numbness), QT prolongation (potentially fatal heart rhythm disorder), severe hepatotoxicity (liver failure, which has been fatal in some cases), aortic aneurysm and dissection, and Clostridioides difficile-associated diarrhoea. Some of these effects, particularly tendon damage and neuropathy, can be long-lasting or permanent. These risks are the reason fluoroquinolones carry an FDA black box warning.
Antacids containing magnesium or aluminium, iron supplements, zinc supplements, sucralfate, and didanosine all significantly reduce moxifloxacin absorption. If you need to take any of these products, you must separate the doses by at least 6 hours — take moxifloxacin either 6 hours before or 6 hours after the interfering product. Never take activated charcoal at the same time as moxifloxacin. Food and dairy products do not affect moxifloxacin absorption.
Treatment duration varies by indication: 7 days for acute bacterial sinusitis, 5–10 days for acute exacerbation of chronic bronchitis, 10 days for community-acquired pneumonia, and 14 days for pelvic inflammatory disease. When switching from IV to oral therapy, total treatment may last 7–14 days for pneumonia or 7–21 days for skin infections. It is critically important to complete the full course even if you feel better, as stopping early can lead to treatment failure and antibiotic resistance.
Moxifloxacin Krka is contraindicated in: patients under 18 years of age; pregnant or breastfeeding women; anyone allergic to moxifloxacin or other fluoroquinolones; patients with a history of tendon disorders from quinolone use; patients with QT prolongation, bradycardia, heart failure, or electrolyte imbalances (low potassium or magnesium); patients taking other QT-prolonging medications; and patients with severe liver disease (transaminases >5x upper limit of normal).
Yes, this is one of the most important safety concerns with moxifloxacin. It must not be combined with any drug that prolongs the QT interval, including antiarrhythmics (amiodarone, sotalol, quinidine, disopyramide), certain antipsychotics (haloperidol, pimozide), and tricyclic antidepressants. Medications that lower potassium levels (diuretics, certain laxatives, corticosteroids) also increase the risk of dangerous heart rhythm disturbances. Always provide your doctor with a complete list of all medications you take.
References
This article is based on the following peer-reviewed sources and regulatory documents:
- European Medicines Agency (EMA). Moxifloxacin — Summary of Product Characteristics. European Medicines Agency. Updated 2025.
- U.S. Food and Drug Administration (FDA). FDA Drug Safety Communication: FDA updates warnings for oral and injectable fluoroquinolone antibiotics due to disabling side effects. FDA Safety Announcements. 2018.
- World Health Organization (WHO). WHO Model List of Essential Medicines — 23rd List. World Health Organization. 2023.
- British National Formulary (BNF). Moxifloxacin monograph. National Institute for Health and Care Excellence. Updated 2025.
- Mandell LA, Wunderink RG, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clinical Infectious Diseases. 2019;44(Suppl 2):S27–72.
- EMA Pharmacovigilance Risk Assessment Committee (PRAC). Fluoroquinolone and quinolone antibiotics: PRAC recommends restrictions on use. European Medicines Agency. 2018.
- Daneman N, Lu H, Redelmeier DA. Fluoroquinolones and collagen associated severe adverse events: a longitudinal cohort study. BMJ Open. 2015;5(11):e010077.
- Etminan M, Brophy JM, Samii A. Oral fluoroquinolone use and risk of peripheral neuropathy: a pharmacoepidemiologic study. Neurology. 2014;83(14):1261–1263.
Medical Editorial Team
Written by
iMedic Medical Editorial Team
Specialists in clinical pharmacology and infectious disease with documented academic background and clinical experience.
Reviewed by
iMedic Medical Review Board
Independent panel of medical experts who review all content according to international guidelines (WHO, EMA, FDA, BNF).
Evidence Framework: All medical claims in this article are supported by Level 1A evidence (systematic reviews and meta-analyses of randomised controlled trials) or official regulatory documents from the EMA and FDA. Content follows the GRADE evidence framework.
Conflict of Interest: No commercial funding. Independent medical editorial content with no pharmaceutical company sponsorship.