Zimax 500

Indications

Zimax serves as a treatment for infections caused by susceptible organisms in various conditions. These include lower respiratory tract infections like bronchitis and pneumonia, upper respiratory tract infections such as sinusitis and pharyngitis/tonsillitis, otitis media, and skin and soft tissue infections. In sexually transmitted diseases in both men and women, Zimax is effective in treating non-gonococcal urethritis and cervicitis caused by Chlamydia trachomatis.

Pharmacology

Azithromycin, being acid-stable, can be orally taken without the need for protection from gastric acids. Its absorption is optimal, especially on an empty stomach. In adults, the time to peak concentration ranges from 2.1 to 3.2 hours for oral dosage forms. Azithromycin exhibits high concentration in phagocytes, facilitating active transport to the site of infection. This high tissue concentration, exceeding plasma levels by over 50 times, is attributed to ion trapping and high lipid solubility.

Azithromycin’s extended half-life allows for a large single dose administration while maintaining bacteriostatic levels in infected tissues for several days. Following a single 500 mg dose, plasma concentrations of azithromycin exhibit a polyphasic decline pattern, with a mean apparent plasma clearance of 630 mL/min and a terminal elimination half-life of 68 hours. The prolonged half-life results from extensive uptake and subsequent release of the drug from tissues. Biliary excretion, predominantly unchanged, serves as a major elimination route. Approximately 6% of the administered dose appears as unchanged drug in urine over the course of a week.

Microbiology

Azithromycin exerts its action by binding to the 50S ribosomal subunit of susceptible microorganisms, thereby interfering with microbial protein synthesis. Notably, nucleic acid synthesis remains unaffected. Azithromycin demonstrates activity against various microorganisms, both in vitro and in clinical infections, including aerobic and facultative gram-positive and gram-negative microorganisms, as well as certain anaerobic microorganisms.

Dosage

For oral administration in adults, Zimax is typically prescribed as 500 mg once daily orally for 3 days or 500 mg once on day 1, followed by 250 mg once daily for the next 4 days. In pediatric patients, dosages vary based on body weight and indication. For sexually transmitted diseases caused by Chlamydia trachomatis in adults, the recommended dose is 1 gm given as a single dose or 500 mg once on day 1, followed by 250 mg once daily for the next 2 days.

For injection, the recommended dose for adult patients with community-acquired pneumonia is typically 500 mg as a single daily dose by the intravenous route for at least two days, followed by oral administration to complete a 7 to 10-day course of therapy.

Administration

Reconstitution of the suspension involves shaking the bottle well to loosen the powder, adding boiled and cooled water up to the water mark of the bottle label, and shaking until the powder is completely mixed with water. Azithromycin should be taken at least 1 hour before or 2 hours after a meal.

Interaction

Interactions with other medications should be noted, such as the timing of administration with antacids, potential effects on drugs like carbamazepine, cyclosporine, digoxin, ergot derivatives, methylprednisolone, theophylline, warfarin, and terfenadine.

Contraindications

Zimax is contraindicated in patients hypersensitive to Azithromycin or any other macrolide antibiotic, in those with hepatic diseases, and when co-administered with ergot derivatives.

Side Effects

While generally well-tolerated, Zimax may cause mild to moderate side effects, predominantly gastrointestinal in origin. Allergic reactions, reversible elevations in liver transaminases, and hearing impairment have been reported in rare cases.

Pregnancy & Lactation

Azithromycin falls under Pregnancy Category B, indicating no evidence of harm to the fetus based on animal reproduction studies. However, caution is advised during pregnancy, and its use during lactation requires careful consideration.

Precautions & Warnings

Special precautions should be taken regarding serious allergic reactions, use in patients with renal or hepatic impairment, and its effects on driving or operating machinery.

Overdose Effects

While data on overdosage with Zimax is limited, typical symptoms of macrolide antibiotic overdose include hearing loss, severe nausea, vomiting, and diarrhea. General supportive measures are recommended.

Storage Conditions

Zimax should be stored in a dry place away from light and heat, and kept out of reach of children.

Chemical Structure

Zimax’s molecular formula is C38H72N2O12, and its chemical structure is that of Azithromycin Dihydrate.

Common Questions

Common queries regarding Zimax, its uses, side effects, storage, and safety precautions are addressed, providing valuable information to users.