Zithrin Suspension 50ml

Zithrin is indicated for the treatment of infections caused by susceptible microorganisms. It is commonly prescribed for:

• Lower respiratory tract infections, including bronchitis and community-acquired pneumonia
• Upper respiratory tract infections such as sinusitis, pharyngitis, and tonsillitis
• Acute otitis media
• Skin and soft tissue infections
• Sexually transmitted infections, including non-gonococcal urethritis and cervicitis caused by Chlamydia trachomatis in both men and women.

Azithromycin is a macrolide antibiotic that remains stable in acidic conditions, allowing it to be taken orally without requiring protection from stomach acid. It is rapidly absorbed after oral administration, with better absorption when taken on an empty stomach. Peak blood concentrations are generally reached within 2.1 to 3.2 hours in adults.

One of its unique properties is its ability to accumulate inside phagocytic cells, which transport the drug directly to infected tissues. During the body's immune response, these cells release high concentrations of azithromycin at the site of infection. Tissue concentrations may become more than 50 times higher than plasma levels due to its high lipid solubility and ion-trapping characteristics.

Azithromycin has a prolonged elimination half-life, allowing once-daily dosing while maintaining therapeutic concentrations in infected tissues for several days. Following a single 500 mg oral dose, the drug demonstrates an average plasma clearance of approximately 630 mL/min and a terminal elimination half-life of about 68 hours. The prolonged half-life results from extensive tissue distribution followed by gradual release into circulation.

The drug is eliminated mainly through the bile in an unchanged form, while approximately 6% of the administered dose is excreted unchanged in the urine within one week.

Azithromycin is active against many clinically important microorganisms, including:

Gram-positive bacteria

• Staphylococcus aureus
• Streptococcus agalactiae
• Streptococcus pneumoniae
• Streptococcus pyogenes
• Group C, F, and G streptococci
• Viridans streptococci

Gram-negative bacteria

• Haemophilus influenzae
• Haemophilus ducreyi
• Moraxella catarrhalis
• Neisseria gonorrhoeae
• Bordetella pertussis
• Legionella pneumophila

Other susceptible organisms

• Chlamydia trachomatis
• Chlamydia pneumoniae
• Mycoplasma pneumoniae

Anaerobic organisms

• Peptostreptococcus species
• Prevotella bivia

Suspension Reconstitution

1. Shake the bottle thoroughly to loosen the dry powder.
2. Add previously boiled and cooled water up to the marked line on the bottle.
3. Shake well until the suspension becomes completely uniform.

For optimal absorption, take azithromycin at least 1 hour before meals or 2 hours after meals.

Use azithromycin cautiously with the following medicines:

• Antacids: Take azithromycin at least 1 hour before or 2 hours after antacids containing aluminum or magnesium.
• Cyclosporine: Monitor cyclosporine blood levels and adjust dosage if necessary.
• Digoxin: May increase digoxin concentrations; monitoring is recommended.
• Warfarin: May be administered together, but regular monitoring of prothrombin time (PT/INR) is advised.
• Theophylline: Although significant interaction is uncommon, monitoring is recommended.
• Carbamazepine: No clinically significant interaction has been observed.
• Methylprednisolone: No significant pharmacokinetic interaction reported.
• Ergot derivatives: Concurrent use is contraindicated because of the potential risk of ergot toxicity.
• Terfenadine: No significant effect on QT interval has been demonstrated at recommended doses.

Zithrin should not be used in patients with:

• Known hypersensitivity to azithromycin or other macrolide antibiotics.
• Concurrent use of ergot alkaloid derivatives.
• Significant hepatic impairment or active liver disease.

Zithrin is generally well tolerated, and most adverse effects are mild and self-limiting.

Common side effects include:

• Nausea
• Vomiting
• Abdominal pain or cramps
• Diarrhea
• Loose stools
• Flatulence

Less common effects include:

• Skin rash
• Photosensitivity
• Temporary elevation of liver enzymes
• Mild reduction in neutrophil count
• Cholestatic jaundice (rare)
• Serious allergic reactions including angioedema or anaphylaxis (rare)
• Reversible hearing impairment with prolonged use of high doses

Pregnancy:
Azithromycin is classified as Pregnancy Category B. Animal studies have shown no evidence of fetal harm; however, adequate studies in pregnant women are lacking. It should be used during pregnancy only when clearly needed and when the expected benefit outweighs potential risks.

Breastfeeding:
It is not known whether azithromycin is excreted into human breast milk. Therefore, it should be used cautiously in nursing mothers after medical evaluation.

Rare but serious allergic reactions, including angioedema and anaphylaxis, have been reported. Some patients may experience recurrent symptoms requiring prolonged medical management.

Patients should promptly seek medical attention if they develop:

Severe allergic reactions

Persistent diarrhea

Jaundice or signs of liver dysfunction

Irregular heartbeat

• Store in a cool, dry place.
• Protect from light and excessive heat.
• Keep out of the reach of children.