Description

5-Nok (Nitroxoline) – Coated Tablets 50 mg №50

Composition

Each coated tablet contains:

• Nitroxoline 50 mg
• Excipients: lactose monohydrate, maize starch, magnesium stearate, talc, colloidal silica, and coating agents.

Pharmacological Properties

Nitroxoline is an antibacterial agent from the 8-hydroxyquinoline group. Its mechanism of action is based on the inhibition of bacterial DNA synthesis through the chelation of metal ions necessary for enzymatic activity. This interference disrupts metabolic functions critical to bacterial survival, particularly in the urinary tract environment.

The drug exhibits a bacteriostatic and bactericidal effect against a broad spectrum of Gram-positive and Gram-negative organisms, including Escherichia coli, Proteus spp., Staphylococcus spp., Klebsiella spp., and Enterobacter spp.. It also demonstrates effectiveness against some fungal strains and atypical pathogens such as Mycobacterium tuberculosis.

Indications

5-Nok is primarily indicated for the treatment and prevention of urinary tract infections (UTIs), including but not limited to:

• Acute and chronic cystitis
• Pyelonephritis
• Urethritis
• Prostatitis
• Epididymitis
• Postoperative prophylaxis after urological procedures (e.g., catheterization, cystoscopy, surgery)

Dosage and Administration

The standard dosage for adults is 400 mg per day, divided into 4 doses of 100 mg (2 tablets) every 6 hours. Duration of therapy is typically 7–14 days but can be adjusted depending on the severity of the infection and response to treatment.

For children over 5 years old, the dosage is usually determined by body weight (approximately 10–30 mg/kg/day). The tablets should be swallowed whole with water, preferably before meals to reduce the risk of gastrointestinal irritation.

Pharmacokinetics

After oral administration, nitroxoline is rapidly absorbed from the gastrointestinal tract, reaching peak plasma concentrations within 1.5–2 hours. It is largely unmetabolized and excreted in the urine, where it retains its active form. This high urinary concentration is a key factor in its efficacy for UTI treatment.

Contraindications

• Hypersensitivity to nitroxoline or other quinoline derivatives
• Severe renal insufficiency (creatinine clearance < 20 mL/min)
• Cataracts
• Pregnancy and lactation
• Children under 5 years of age

Side Effects

5-Nok is generally well tolerated, but possible side effects may include:

• Gastrointestinal disturbances (nausea, vomiting, abdominal discomfort)
• Rash or allergic skin reactions
• Headache or dizziness
• Urine discoloration (orange or yellow) – harmless and expected
• Rarely: peripheral neuropathy, liver enzyme elevation

Precautions

Use with caution in patients with hepatic dysfunction or those on prolonged treatment courses. Periodic monitoring of liver function tests and complete blood counts is advised in such cases. Dosage adjustment may be necessary in elderly individuals with declining renal function.

Drug Interactions

• May enhance the effects of other quinoline-based drugs
• Potential antagonism with nalidixic acid and its derivatives
• Absorption may be reduced by antacids containing magnesium or aluminum

Overdose

Symptoms of overdose may include nausea, vomiting, tremor, and ataxia. There is no specific antidote; treatment is symptomatic and supportive. Increased fluid intake is recommended to promote renal elimination of the drug.

Storage Conditions

Store at room temperature (15–25°C), in a dry place protected from direct sunlight and moisture. Keep out of reach of children.

Packaging

5-Nok is supplied in plastic vials containing 50 coated tablets. Each tablet is round, biconvex, and orange-colored.

Scientific Evidence

A clinical study published in *Antimicrobial Agents and Chemotherapy* confirmed the antibacterial efficacy of nitroxoline against resistant uropathogens, especially Escherichia coli and Klebsiella pneumoniae. This study highlighted its preserved activity despite growing antibiotic resistance, positioning nitroxoline as a valuable therapeutic option in recurrent UTIs:

https://aac.asm.org/content/59/12/7115

Advantages of 5-Nok

• Targeted action on urinary pathogens
• Minimal systemic side effects due to renal excretion
• Effective in chronic and recurrent infections
• Favorable safety profile over long-term use
• Useful in prophylaxis after urological interventions

Patient Experience and Outcomes

Patients report significant relief from symptoms such as pain during urination, frequent urges, and lower abdominal discomfort within 2–3 days of initiation. Full resolution is typically achieved within 7–10 days of consistent therapy.

In prophylactic settings, especially after catheter use or surgery, 5-Nok reduces infection rates and accelerates recovery times, allowing for better postoperative outcomes and shorter hospital stays.

Summary

5-Nok (Nitroxoline) remains a reliable, effective, and accessible option for the treatment and prevention of urinary tract infections. Its unique pharmacological profile and extensive clinical use across decades have solidified its role in urological therapy. With increasing antibiotic resistance worldwide, nitroxoline presents an important alternative for both first-line and adjunctive treatment strategies in managing UTIs.