Azithrocine

Quick links to important sections

Medically reviewed

Rosario Oropesa

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Azithrocine

What is Azithrocine?

Azithrocine is a pharmaceutical formulation containing azithromycin, which belongs to a class of medications known as macrolide antibiotics. It is primarily utilized to address various types of bacterial infections by interfering with the way bacteria produce proteins necessary for their growth and survival.

Therapeutic Class and Mechanism

As a macrolide, Azithrocine works by binding to the 50S subunit of the bacterial ribosome. This action inhibits RNA-dependent protein synthesis, preventing the bacteria from multiplying. Because it stops bacterial growth rather than killing the bacteria outright, it is classified as a bacteriostatic antibiotic, although it can be bactericidal against certain organisms at higher concentrations.

Primary Uses

This medication is typically indicated for the treatment of mild to moderate infections caused by susceptible strains of microorganisms. Common areas of application include:

  • Respiratory Tract Infections: Such as acute bacterial exacerbations of chronic obstructive pulmonary disease (COPD), pneumonia, and sinusitis.
  • Throat and Tonsil Infections: Including pharyngitis and tonsillitis.
  • Skin and Soft Tissue Infections: Addressing uncomplicated infections of the skin structure.
  • Genitourinary Infections: Specifically non-gonococcal urethritis and cervicitis.

Pharmacological Properties

Azithrocine is characterized by its significant tissue penetration and a long elimination half-life. These properties allow the medication to remain active in the body for an extended period, which often results in shorter treatment courses compared to other antibiotic classes. It is rapidly absorbed following administration and distributed widely throughout the body, concentrating specifically in fibroblasts and phagocytes, which helps deliver the active ingredient to the site of infection.

Regulatory References

  1. NIH/MedlinePlus: Azithromycin Tissue Penetration

What side effects are possible with Azithrocine?

Possible side effects and safety information

The safety profile of Azithrocine (Azithromycin) is classified by regulatory authorities based on the frequency and system-organ class of reported adverse reactions. The most Very Common side effects listed in official documents primarily involve Gastrointestinal disorders, such as diarrhea, abdominal pain, nausea, and loose stools. Other Common reactions include vomiting, headache, dizziness, and fatigue.


Serious Adverse Reactions

The regulatory label explicitly documents the potential for serious adverse reactions, which, while rare, are clinically significant. These include severe Hepatotoxicity (e.g., hepatic necrosis, hepatic failure), serious Cardiac disorders such as QT prolongation and Torsades de Pointes, and potentially fatal Severe Hypersensitivity Reactions (including DRESS, Stevens-Johnson Syndrome, and Toxic Epidermal Necrolysis). The potential for Clostridioides difficile-Associated Diarrhea (CDAD) is also noted.


Population-Specific and Time-Related Safety Notes

Specific safety considerations are documented for certain populations. For instance, Neonates (up to 42 days of life) have reported cases of Infantile Hypertrophic Pyloric Stenosis (IHPS). Caution is advised for patients with severe renal impairment due to increased systemic exposure, and the drug is contraindicated in individuals with a history of macrolide-associated hepatic dysfunction. The official label also notes that the short-term potential risk of acute cardiovascular death has been observed to be greater during the first five days of use.

Overdose and Emergency Response

The official regulatory profile for Azithrocine overdosage is structured by documented clinical presentations, mandated emergency actions, and required supportive care.

Category Official Regulatory Statement
Documented Overdose Presentations Manifestations experienced in higher than recommended doses are similar to those seen at normal therapeutic doses, specifically nausea, vomiting, diarrhea, and stomach discomfort. The primary system affected is the Gastrointestinal system.
Emergency Help Required When Immediate medical attention must be sought for severe signs, including seizure, collapse, or trouble breathing. Contact a Poison Control Centre or emergency services immediately if overdose is suspected.
Serious Outcomes & Risk Factors There is a documented risk of Prolongation of the QT interval and Torsades de pointes, which can lead to potentially fatal cardiac arrhythmia with high exposure. Women and elderly patients are noted to be at increased risk for these ventricular arrhythmias.

Management of an Azithrocine overdose is officially defined by regulatory bodies as the provision of general symptomatic and supportive measures as required. There is no specific antidote documented in the official regulatory product information. The official profile emphasizes that although the initial symptoms are primarily gastrointestinal, the potential for life-threatening cardiac events necessitates immediate medical assessment and care.

Therapeutic Uses of Azithrocine

What Azithrocine Treats: Main Uses and Benefits

Azithromycin is a macrolide antibacterial drug commonly used to help with infections caused by susceptible bacteria. It is applied in addressing conditions involving episodic or fluctuating manifestations across various organ systems.

The medication is considered relevant for easing conditions involving the respiratory tract (such as community-acquired pneumonia, acute bacterial sinusitis, and acute bacterial exacerbations of chronic bronchitis), the upper respiratory and ear (like pharyngitis/tonsillitis and acute otitis media), skin and skin structure, and the genital tract (including urethritis, cervicitis, and genital ulcer disease).

This medication may assist with easing symptoms related to physical discomfort. It supports general well-being during symptomatic phases and provides support that helps ease the overall symptom burden in situations where patients experience these conditions.

“The treatment is commonly used to help with acute or disruptive symptom patterns linked to organ-specific functional stress.”


Quick Fact: Relief for Symptoms Related to Inflammatory or Irritative States

Eligibility and Restrictions for Use

Who Can and Cannot Use Azithrocine?

The official population eligibility for Azithrocine (Azithromycin) is determined by governmental regulatory bodies and defines absolute prohibitions, restrictions, and conditional use based on patient characteristics and pre-existing health status.


Contraindicated Populations

Use of Azithrocine is absolutely contraindicated for patients with a known hypersensitivity to azithromycin, erythromycin, or any macrolide/ketolide antibiotic. It must also not be used by patients with a history of cholestatic jaundice or hepatic dysfunction specifically associated with prior azithromycin therapy. Additionally, use is strictly limited in patients with known QT prolongation or risk factors for Torsades de Pointes.


Population-Specific Restrictions

Eligibility is restricted for certain age and health groups:

  • Pediatric Use: Safety and effectiveness are not established for infants under six months of age. Tablets are not suitable for children weighing less than 45 kg.
  • Organ Impairment: The medicine is not recommended for patients with severe hepatic impairment (e.g., Child-Pugh Class C) and requires caution in cases of severe renal impairment.
  • Other Comorbidities: Caution is required for older adults and patients with Myasthenia Gravis or proarrhythmic conditions.
  • Reproductive Status: Use during pregnancy or lactation is typically restricted to situations where the benefit clearly outweighs the potential risk, as documented in official labeling.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The interaction profile for Azithrocine (Azithromycin) is strictly defined by pharmacokinetic (PK) and pharmacodynamic (PD) information documented in official government regulatory sources.

Contraindicated Combinations and Major Restrictions

Classification Interacting Agents Official Restriction
Contraindicated Pimozide, Ergot Derivatives (e.g., Ergotamine) Prohibited due to severe risk of cardiac arrhythmias or ergotism.
Exposure-Altering Interactions Nelfinavir Increases Azithrocine systemic exposure (AUC and Cmax).
Timing Requirement Aluminum/Magnesium Antacids Co-administration must be separated by 2 hours to avoid reducing Azithrocine Cmax.

Pharmacokinetic and Pharmacodynamic Effects Azithrocine is formally documented as an inhibitor of the P-glycoprotein efflux transporter. This action increases the plasma concentration and overall exposure of co-administered P-gp substrates, such as Digoxin and Colchicine, a change that necessitates monitoring. The drug also presents a pharmacodynamic risk of additive QTc interval prolongation when combined with other QTc prolonging agents, which may lead to serious ventricular arrhythmias. When administered with Warfarin, Azithrocine may elevate the International Normalized Ratio (INR), requiring close coagulation testing. Population-specific notes confirm that elderly and women have an increased risk for the cardiac arrhythmia interaction, and minor PK changes are observed in cases of renal impairment.

Mechanism of Action

Azithrocine, containing the active substance Azithromycin, exerts its effect through a dual mechanism: a primary, targeted inhibition of bacterial protein synthesis and a secondary modulation of host inflammatory pathways.


Blocking Bacterial Protein Synthesis

The molecule functions as a non-competitive inhibitor, binding specifically to the 23S ribosomal RNA (rRNA) component within the bacterial 50S ribosomal subunit. This binding physically obstructs the peptide exit tunnel, which halts the process of peptidyl translocation. The consequence of this molecular blockade is the arrest of protein chain elongation, resulting in bacteriostasis.


Modulation of Inflammation and Tissue Targeting

Azithromycin is actively concentrated by phagocytes (immune cells), ensuring high drug levels are delivered to target tissues. Once accumulated, the molecule modulates the host inflammatory cascade by reducing the synthesis and release of pro-inflammatory cytokines such as Interleukin-8. This mechanism adjusts overactive physiological responses, resulting in reduced synthesis of inflammatory mediators and modulation of local cellular activity.

Dosage and Administration Information

How to Use Azithrocine: Official Administration Guidelines

Azithrocine (Azithromycin) administration is governed by specific parameters defining the approved routes, dosing patterns, and intake conditions. The medicine is officially administered through the Oral (PO) route using tablets, capsules, or suspensions, or via Intravenous (IV) infusion. The choice between routes often depends on the clinical context, with IV use typically initiating treatment for more severe cases, followed by a switch to oral therapy.

Standard adult usage follows defined total dose and duration principles. The most common regimens are the 3-day course (500 mg once daily for three days) or the 5-day course (a 500 mg loading dose on Day 1, followed by 250 mg once daily for four additional days), resulting in a total administered dose of 1,500 mg. Single, high-dose regimens of 1,000 mg or 2,000 mg are also prescribed for specific uses.

Intake Conditions and Special Rules

Administration Aspect Official Instruction
Timing with Food (Standard Forms) May be taken with or without food.
Timing with Food (Extended-Release) Must be taken on an empty stomach (1 hour before or 2 hours after a meal).
IV Infusion Rate Must be administered as a slow infusion over 60 minutes.
Antacid Separation Separate from aluminum- or magnesium-containing antacids by 1 hour before or 2 hours after.

For pediatric use, dosing for children (six months and older) is calculated based on body weight (mg/kg) using the oral suspension. If a scheduled dose is missed, it should be taken immediately unless close to the next dose, at which point the patient should resume the standard schedule.

Recent Clinical Evidence

Research evidence / Overview of studies for Azithrocine

Evidence for Respiratory and Ear Infections

Clinical development for Azithrocine primarily relied on Randomized Controlled Trials (RCTs) and systematic reviews, which compared it to other antibiotic regimens used in the research setting for bacterial infections. For Community-Acquired Pneumonia (CAP), research was studied for its use in adults and children, often stratified by how severe the condition was. These trials monitored outcomes related to systemic or functional imbalance, such as changes in clinical symptoms and the measurement of microbiological clearance of common respiratory pathogens. Findings describe patterns observed in the studies related to short-term symptom changes shortly after the treatment period was completed.

Similarly, research for Acute Otitis Media (AOM) in pediatric populations was evaluated in RCTs to assess outcomes related to physical discomfort and microbiological clearance. Studies specifically monitored measurements of symptom change at defined follow-up visits, which typically occurred in the intermediate term (around two weeks to one month).

For Acute Bacterial Exacerbations of Chronic Bronchitis (ABECB), studies explored the use of Azithrocine in adults during periods of heightened symptom activity. Research focused on whether the drug was associated with changes measured during the study period for both the acute episode and the examination of subsequent exacerbation frequency.


Evidence for Skin and Sexually Transmitted Infections

Azithrocine was studied for uncomplicated Skin and Skin Structure Infections to assess outcomes related to physical discomfort and bacterial clearance in adult populations. The research explored short-term changes in these infections following treatment.

For genital tract infections, including uncomplicated Urethritis, Cervicitis, and Chancroid, the evidence focuses heavily on microbiological eradication rates, which means the measure of whether the target bacteria were cleared from the infected site. The data show patterns related to the time course and observed persistence of microbiological clearance across a defined time interval.


Evidence Quality, Gaps, and Uncertainty

Overall, the evidence for major, established indications like CAP and AOM is categorized as High based on regulatory reviews of large-scale Randomized Controlled Trials. However, the evidence consistency varies across studies for other, less common infections.

What is still uncertain relates primarily to the long-term effects are not fully established following acute treatment. Furthermore, the global challenge of antimicrobial resistance means that data are still emerging regarding how bacterial susceptibility to Azithrocine may change over time and in different geographical areas.

It is critical to understand that this research provides context but not individual predictions. The findings describe group patterns, not personal outcomes, and research does not determine whether an individual will respond similarly.

Frequently Asked Questions (FAQ)

Common questions about Azithrocine (FAQ)


Q: Can taking Azithrocine make you more sensitive to the sun?

Official information documents the potential for increased sensitivity of the skin to sunlight, a condition sometimes called photosensitivity. This means some individuals may experience severe sunburn or other reactions more easily when exposed to the sun while using this medicine. It is a documented reaction, although its frequency is not commonly reported.

Q: Can Azithrocine be taken with pain relievers like Tylenol (acetaminophen)?

Authoritative sources typically do not list a specific pharmacological interaction between Azithrocine and pain relievers such as acetaminophen. However, it is noted that Azithrocine has warnings regarding the potential for liver injury. Since taking high doses of acetaminophen is also associated with a risk to the liver, this general risk is noted in medical contexts.

Q: Does Azithrocine interact with birth control pills?

Official drug interaction databases suggest that Azithrocine (Azithromycin) is generally not expected to reduce the effectiveness of hormonal contraceptives (birth control pills). Regulatory notes caution that gastrointestinal events, which are known side effects, could affect the general absorption of any oral medication, including contraceptives.

Q: Can Azithrocine cause headaches?

Yes, headaches are listed in official regulatory documents as a Common side effect associated with the use of Azithrocine. This means that headaches are among the frequently reported adverse reactions.

Q: Is it normal to have mild diarrhea when taking Azithrocine?

Yes, regulatory documentation lists diarrhea as a Very Common side effect, meaning it is one of the most frequently reported gastrointestinal issues. Severe or persistent diarrhea is a factor that may require medical evaluation, as official warnings note the potential for a more serious condition called Clostridioides difficile-associated diarrhea (CDAD).

Q: Can Azithrocine be used to treat viral infections like the common cold?

Official regulatory documents clearly state that Azithrocine is an antibacterial drug that is only approved to treat infections caused by susceptible bacteria. It does not treat infections caused by viruses, such as the common cold, the flu, or most upper respiratory infections.

Q: Can older adults take Azithrocine?

Official information confirms that Azithrocine is used in older adults. However, these patients may have an increased risk for certain drug-related cardiac side effects, specifically irregular heart rhythms. The official label notes that caution is required when prescribing for older adults.

Q: Does Azithrocine work right away after I take the first tablet?

The drug’s antibacterial action begins once the active compound reaches the site of the infection. Regulatory studies show that Azithrocine achieves high and sustained concentrations in tissue (such as the lung and skin) very quickly. Clinical response varies by individual and the specific infection being treated.

Q: How long does Azithrocine stay in your system after the last dose?

Azithrocine has a prolonged presence in the body, which is related to its ability to concentrate in tissue. Official pharmacokinetic data describes an average terminal elimination half-life of 68 hours following oral doses. This means it takes approximately 68 hours for the concentration of the drug in the plasma to be reduced by half.

Q: What is the difference between Azithrocine and other common antibiotics?

Azithrocine belongs to a specific class of drugs called azalide macrolide antibiotics. A key characteristic described in official documents is its ability to be extensively absorbed by tissues, resulting in high and sustained concentrations at the site of infection. This unique property is what is noted as relating to its shorter treatment regimens compared to many other types of antibiotics.

Q: What happens if I take Azithrocine with certain antacids?

Official regulatory documents specify that taking Azithrocine simultaneously with antacids that contain aluminum or magnesium can reduce the amount of Azithrocine absorbed into the blood. Therefore, official guidelines require a specific timing separation between taking the antibiotic and the antacid.

Q: Are there any specific foods that interact with Azithrocine?

For the standard oral tablet form of Azithrocine, official administration guidelines state it may be taken with or without food. However, the extended-release oral suspension (a specialized liquid form) is documented in official sources as needing to be taken on an empty stomach.

Q: Is there any information about using Azithrocine during pregnancy?

Official regulatory labels note that the data regarding Azithrocine use in pregnant women are insufficient to draw conclusions about the risk of developmental harm. As a result, use during pregnancy is described in official documents as being reserved for situations where the potential benefit is judged to justify the potential risk.

Q: What do official documents say about Azithrocine and breastfeeding?

Official data confirms that Azithrocine is present in human milk due to its long half-life. While current information suggests that because of the low levels in breastmilk, adverse effects on the infant are generally not expected, official information includes notes on monitoring the infant for potential gastrointestinal issues or fungal infections.

Q: Do studies suggest Azithrocine is effective for respiratory infections?

Regulatory documents confirm that clinical studies have been conducted for established indications such as Community-Acquired Pneumonia (CAP) and Acute Bacterial Exacerbations of Chronic Bronchitis (ABECB). The outcomes reported in these studies support the official use of the product for these bacterial respiratory infections.

Q: What kind of research has been done on Azithrocine for skin infections?

Clinical trials described in regulatory documents confirm that Azithrocine has been studied for the treatment of uncomplicated Skin and Skin Structure Infections. This research monitors outcomes related to physical symptoms and bacterial clearance and supports the established use of the product for these specific bacterial infections in adults.

Q: What is the risk of an allergic reaction to Azithrocine?

Official warnings document the potential for severe hypersensitivity reactions (allergic reactions), which can include conditions like Stevens-Johnson Syndrome. These reactions are rare but can be serious or potentially fatal. Patients are warned that such reactions may recur, even after the initial treatment has been stopped.

Q: Is it true that Azithrocine has a longer-lasting effect than some other antibiotics?

Yes, official pharmacokinetic data describes a prolonged presence of the drug in the body, which is directly related to its ability to concentrate extensively in bodily tissues. This characteristic is why the drug is associated with a long terminal elimination half-life of 68 hours and is often prescribed in shorter courses.

Q: What should I know about the risk of Clostridium difficile (C. diff) with Azithrocine?

Official warnings note that Azithrocine, like nearly all antibacterial agents, has been reported to cause Clostridioides difficile-Associated Diarrhea (CDAD). This condition results from an overgrowth of bacteria in the colon and can range in severity from mild diarrhea to a life-threatening form of colitis.

Q: Is a metallic taste in the mouth a common complaint with Azithrocine?

Changes in taste or smell, including a metallic taste, are documented in some official lists of adverse reactions. However, these are generally categorized as less common or post-marketing events, rather than the most frequently reported side effects like nausea or diarrhea.

Q: Does Azithrocine affect sleep?

The official list of documented side effects includes insomnia (difficulty falling or staying asleep) as an uncommon reaction. Other reports classify somnolence (drowsiness) as a reaction with an unknown frequency.

Q: What is known about Azithrocine's potential to cause hearing issues?

Official information documents cases of hearing impairment, deafness, and/or tinnitus (ringing in the ears) in patients receiving Azithrocine. These reports were most frequent in specific clinical trials involving high-dose regimens. Individuals who have experienced these symptoms have been noted as requiring monitoring.

Q: Can Azithrocine be used for long-term conditions?

The primary official indications for Azithrocine generally describe short treatment courses, such as 3-day or 5-day regimens. However, official documents describe specific, extended use (such as a 22-day daily dosing) that is reserved for a defined indication in certain patient populations (e.g., HIV patients). Extended use is reserved for defined clinical situations.

Q: What is the difference between Azithrocine tablets and the liquid suspension?

Beyond the physical form, the main regulatory difference is in the intake conditions. The standard tablet can be taken with or without food. However, the extended-release oral suspension must be taken on an empty stomach to ensure proper absorption, as specified in official guidelines.

Q: Do studies support the use of Azithrocine for ear infections?

Yes, official regulatory documents confirm that clinical trials for Acute Otitis Media (AOM), a common type of ear infection, have been conducted. The reported outcomes from these studies support the established use of the product for this bacterial infection, particularly in pediatric patients.

Q: Are there specific conditions where Azithrocine use is not recommended?

Yes, official documents specify conditions where use is contraindicated (absolutely prohibited). These include a known allergy to any macrolide antibiotic or a history of specific liver dysfunction caused by prior use of the drug. Official documents also note that caution is required for patients with Myasthenia Gravis or certain pre-existing cardiac conditions.

Q: What is the general duration of treatment for Azithrocine?

The general duration is shorter than many other antibiotics due to its unique pharmacological properties. Official dosing guidelines describe the most common treatment courses as a 3-day course or a 5-day course. However, the duration can vary depending on the specific infection being addressed.

Q: What is the purpose of the different strengths (e.g., 250 mg, 500 mg) of Azithrocine?

The different strengths are intended to allow healthcare providers to precisely meet the total dose required for treatment. Official dosing guidelines show that the strength chosen is based on the type of infection being treated and the specific regimen, such as using a higher strength for an initial 'loading dose' followed by lower maintenance doses.

Q: Are women more likely to experience certain side effects from Azithrocine than men?

Official information documents that women are included in the patient group that has an increased risk for specific drug-related cardiac side effects. This risk relates to the potential for QTc prolongation and the development of irregular heart rhythms, compared to men.

Q: Does Azithrocine have a black box warning in the US?

Azithrocine does not currently have a Black Box Warning (the highest-level FDA warning). However, the label contains a prominent Warning and Precaution section. This section provides detailed information about the serious potential risks, such as the risk of QTc prolongation and potentially fatal irregular heart rhythms.

Q: Why might a doctor prescribe a shorter course of Azithrocine compared to other antibiotics?

Official documents indicate that the ability to use shorter courses stems from the drug’s high apparent volume of distribution and its long terminal elimination half-life of 68 hours. This pharmacokinetic characteristic allows the drug to accumulate and remain at therapeutic levels in the tissue for several days after the last dose.

Q: Is it necessary to finish all the Azithrocine even if I feel better?

Official patient counseling information states that the medicine should be taken exactly as directed by the healthcare provider, even if the patient starts to feel better early in the course of therapy. This course of action is recommended in the official patient counseling information to reduce the potential for developing drug-resistant bacteria.

Q: Why do some people call Azithrocine a 'Z-Pak'?

'Z-Pak' is a well-known proprietary brand name for Azithrocine (Azithromycin) in a pre-packaged, multi-dose blister container format. It is a common colloquial name derived from this specific brand presentation.

Q: Is there a known interaction between Azithrocine and alcohol?

No dangerous pharmacokinetic interaction is explicitly listed on primary regulatory labels. However, alcohol consumption may potentially worsen common side effects of the antibiotic, such as dizziness, nausea, and headache. Guidance from a prescribing healthcare professional is the appropriate source for specific advice on concurrent use.

How should Azithrocine be stored and disposed of?

Storage and Disposal of Azithrocine (Azithromycin)

Storage Requirements

Azithromycin Tablets and Dry Powder must be stored at controlled room temperature, typically 20 C–25 C, away from excess heat and moisture, in their tightly closed original container. The medication must be kept out of the sight and reach of children.

Oral Suspensions (liquid form) have limited stability after mixing. The standard suspension is stable for 10 days and should not be frozen. The extended-release suspension must be used or discarded within 12 hours and must not be refrigerated.

Disposal Instructions

Unused or expired Azithrocine should be disposed of via a drug take-back program as the preferred method. If unavailable, it should be mixed with an undesirable substance (e.g., coffee grounds) and sealed in a container for household trash. Azithromycin is not recommended for flushing down the toilet.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Azithrocine found in:

A-Z Index: