Orasquin320 mg

Orasquin is a fluoroquinolone antibacterial approved for the treatment of specific bacterial infections in adults caused by susceptible strains of designated microorganisms. Because fluoroquinolones as a class carry a risk of serious, potentially irreversible adverse effects, Orasquin should be reserved for patients who have no other appropriate treatment options for the following indications.

Established (FDA-Approved) Uses

• Acute bacterial exacerbation of chronic bronchitis (ABECB) caused by Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, or Moraxella catarrhalis.
• Community-acquired pneumonia (mild to moderate), including cases caused by multi-drug-resistant strains of S. pneumoniae, H. influenzae, M. catarrhalis, Mycoplasma pneumoniae, Chlamydophila pneumoniae, or Klebsiella pneumoniae.

Orasquin is not indicated for uncomplicated infections that typically respond to narrower-spectrum agents; culture and susceptibility data should guide therapy whenever possible.

Each film-coated tablet contains Gemifloxacin mesylate equivalent to 320 mg of Gemifloxacin base, along with standard pharmaceutical excipients used in tablet formulation.

Orasquin is a synthetic, broad-spectrum fluoroquinolone antibacterial agent given by the oral route. It is chemically related to other fluoroquinolones (such as levofloxacin and moxifloxacin) but has a distinct substitution pattern that enhances activity against Streptococcus pneumoniae, including some strains resistant to older fluoroquinolones. Orasquin is bactericidal and is used specifically for lower respiratory tract infections.

Orasquin belongs to the fluoroquinolone class of antibacterial agents.

Gemifloxacin exerts its bactericidal effect by inhibiting two essential bacterial enzymes, DNA gyrase (topoisomerase II) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination. Gemifloxacin shows a distinctive "dual-targeting" action against Streptococcus pneumoniae, retaining activity even against some strains that carry mutations conferring resistance to other fluoroquinolones.

Pharmacokinetics

• Absorption: Rapidly absorbed after oral administration; peak plasma concentration reached in about 0.5–2 hours; absolute oral bioavailability is approximately 71%.
• Distribution: Approximately 60–70% bound to plasma proteins; achieves high concentrations in lung tissue and respiratory fluids.
• Metabolism: Undergoes limited hepatic metabolism; most circulating drug is unchanged.
• Excretion: Eliminated via both fecal (~61%) and renal (~36%) routes; mean elimination half-life is approximately 7 hours.

Orasquin tablets can be taken with or without food, and should be swallowed whole with plenty of liquid. Avoid taking antacids, sucralfate, or mineral supplements (aluminum, magnesium, iron, zinc) at the same time as Orasquin; if needed, separate dosing by several hours (see Interactions). Complete the full course as prescribed.

The following interactions with Orasquin are clinically significant and well documented:

• Antacids and multivalent cations (aluminum, magnesium, iron, zinc): Co-administration substantially reduces absorption of Orasquin through chelation, markedly lowering plasma concentrations and potentially reducing antibacterial effect. Administer Orasquin at least 3 hours before or 2 hours after these products.
• Sucralfate: Similarly reduces Orasquin absorption when taken before Orasquin; administer Orasquin at least 2 hours before sucralfate.
• Warfarin and other oral anticoagulants: Although controlled studies did not show a significant pharmacokinetic interaction, post-marketing reports describe increased anticoagulant effect (elevated INR/PT) and bleeding with concomitant fluoroquinolone use. Monitor coagulation parameters closely if used together.
• Drugs that prolong the QT interval (e.g., Class IA antiarrhythmics such as quinidine and procainamide, Class III antiarrhythmics such as amiodarone and sotalol): Concomitant use increases the risk of additive QT prolongation and should be avoided.
• Probenecid: Increases Orasquin plasma concentration by reducing its renal clearance; dose adjustment is generally not required at standard doses but clinical monitoring is prudent.
• Non-steroidal anti-inflammatory drugs (NSAIDs): Concomitant use with fluoroquinolones may increase the risk of central nervous system stimulation and seizures.

The most commonly reported adverse effects of Orasquin (occurring in ≥2% of patients) are generally mild to moderate and include:

• Diarrhea (~5%)
• Headache (~4%)
• Nausea (~4%)
• Rash (~3.5%, notably higher in young women — see Precautions)
• Abdominal pain
• Vomiting
• Dizziness

Less Common but Clinically Important Effects

Elevated liver enzymes, taste disturbance, insomnia, constipation, dyspepsia, and mild changes in blood counts have also been reported. Serious effects — including tendon injury, peripheral neuropathy, central nervous system effects, QT prolongation, and hypersensitivity reactions — are addressed in detail under Precautions and Warnings, as they require prompt recognition and discontinuation of Orasquin rather than routine management.

Pregnancy: Orasquin corresponds to the older FDA Pregnancy Category C. Animal reproduction studies showed fetal growth retardation and, at high exposures, fetal skeletal and ocular malformations. There are no adequate and well-controlled studies of Orasquin in pregnant women, and safety in pregnancy has not been established. Orasquin should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus; consult a physician before use.

Lactation: It is not known whether Orasquin is excreted in human breast milk. Because fluoroquinolones as a class are excreted in breast milk in animal studies and can affect infant cartilage development, Orasquin should not be used during breastfeeding unless the potential benefit to the mother clearly outweighs the potential risk to the breastfed infant; consult a physician before use.

Boxed Warning: Serious, Potentially Irreversible Adverse Reactions

Fluoroquinolones, including Orasquin, are associated with disabling and potentially irreversible serious adverse reactions that can occur together, including tendinitis and tendon rupture, peripheral neuropathy, and central nervous system effects. Orasquin should be discontinued immediately at the first sign of any of these reactions, and use of fluoroquinolones should be avoided in patients who have experienced any of these serious reactions.

Reserve for Limited Use

Because of the cumulative risk of these serious adverse reactions, Orasquin and other fluoroquinolones should be reserved for use in patients who have no alternative treatment options for the approved indications.

Tendinitis and Tendon Rupture

Risk is increased in patients over 60 years of age, those taking corticosteroids, and kidney, heart, or lung transplant recipients. Rupture can occur during or after therapy, and can be bilateral. Discontinue Orasquin and avoid exercise/use of the affected area if tendon pain, swelling, or inflammation occurs.

Peripheral Neuropathy

Sensory or sensorimotor axonal polyneuropathy affecting small and/or large axons can occur rapidly after starting Orasquin and may be irreversible. Discontinue immediately if symptoms of neuropathy (pain, burning, tingling, numbness, weakness) develop.

Central Nervous System Effects

Fluoroquinolones including Orasquin may cause seizures, increased intracranial pressure, dizziness, confusion, tremors, hallucinations, anxiety, depression, insomnia, nightmares, and, rarely, suicidal thoughts. Use with caution in patients with known or suspected CNS disorders.

Exacerbation of Myasthenia Gravis

Orasquin can worsen muscle weakness in patients with myasthenia gravis and is contraindicated in this population (see Contraindications).

Aortic Aneurysm and Dissection

Fluoroquinolones, as a class, are associated with an increased risk of aortic aneurysm and dissection, particularly in elderly patients and those with a history of aortic aneurysm, peripheral atherosclerotic vascular disease, hypertension, or certain genetic connective tissue disorders. Avoid Orasquin in these higher-risk patients unless no alternative therapy is available.

QT Interval Prolongation

Orasquin may prolong the QT interval. Avoid use in patients with known QT prolongation, uncorrected electrolyte abnormalities (e.g., hypokalemia, hypomagnesemia), or concurrent use of Class IA or Class III antiarrhythmic drugs (see Interactions).

Hypersensitivity Reactions

Serious and occasionally fatal hypersensitivity and/or anaphylactic reactions can occur, sometimes after the first dose. Discontinue Orasquin immediately if a rash, jaundice, or any other sign of hypersensitivity occurs.

Rash

Rash occurs more frequently with Orasquin than with many comparator antibiotics and is notably more common in women under 40 years of age, particularly with longer treatment courses. Most rashes are mild to moderate and resolve after stopping treatment, but Orasquin should be discontinued if a rash develops.

Clostridioides difficile-Associated Diarrhea

C. difficile-associated diarrhea, ranging from mild diarrhea to fatal colitis, has been reported with nearly all antibacterial agents, including Orasquin, and may occur weeks after treatment. Consider this diagnosis in patients presenting with diarrhea after Orasquin use.

Photosensitivity

Exaggerated sunburn-type reactions can occur with sun or UV light exposure. Avoid excessive sunlight or artificial UV exposure during treatment.

Development of Drug-Resistant Bacteria

Prescribing Orasquin in the absence of a proven or strongly suspected bacterial infection is unlikely to benefit the patient and increases the risk of the development of drug-resistant bacteria.

There is no specific antidote for Orasquin overdose. In case of a suspected overdose, seek immediate medical attention or contact a poison control center right away. Management is supportive and symptomatic, with careful monitoring of cardiac rhythm (including ECG monitoring for QT prolongation), hydration status, and renal function; hemodialysis removes only a modest fraction of the drug. Do not attempt to manage a suspected overdose at home without medical guidance.

Store at room temperature (below 30°C), protected from light and moisture. Keep out of reach of children.

Renal Impairment

Dose reduction to 160 mg once daily is required when creatinine clearance is ≤40 mL/min, including patients on hemodialysis or continuous ambulatory peritoneal dialysis (see Dosage and Administration).

Hepatic Impairment

No dosage adjustment of Orasquin is required in patients with mild, moderate, or severe hepatic impairment.

Elderly Patients

No dosage adjustment is required based on age alone; however, elderly patients, especially those also taking corticosteroids, are at increased risk of tendon disorders with Orasquin (see Precautions).

Pediatric Patients

Safety and effectiveness of Orasquin in patients under 18 years of age have not been established; use in this population is not recommended (see Pediatric Uses).

Pregnancy and Lactation

See Pregnancy and Lactation section for detailed guidance.

Treatment with Orasquin is typically 5 days for acute bacterial exacerbation of chronic bronchitis and most cases of community-acquired pneumonia. A 7-day course is used for community-acquired pneumonia caused by multi-drug-resistant Streptococcus pneumoniae, Klebsiella pneumoniae, or Moraxella catarrhalis. The full course should be completed as prescribed, even if symptoms improve earlier, to reduce the risk of relapse and antibiotic resistance.

Fluoroquinolone antibacterial (antibiotic).

Gemifloxacin inhibits bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, enzymes essential for bacterial DNA replication, transcription, and repair. By blocking both targets ("dual targeting"), Gemifloxacin produces a bactericidal effect and retains activity against some pneumococcal strains resistant to older fluoroquinolones.

C

The safety and effectiveness of Orasquin in children and adolescents under 18 years of age have not been established. As with other fluoroquinolones, animal data show that this class can cause arthropathy (joint/cartilage damage) in immature animals, raising theoretical concern for similar effects in children. For this reason, Orasquin is generally not recommended for use in pediatric patients unless a physician determines that no safer alternative is appropriate and the potential benefit outweighs the risk.