| HS Code | 294522 |
| Product Name | Azithromycin for injection Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable |
| Api Name | Azithromycin (Azithromycin dihydrate) |
| Cas Number | 83905-01-5 (azithromycin); 117772-70-0 (azithromycin dihydrate) |
| Molecular Formula | C38H72N2O12 (azithromycin); C38H72N2O12·2H2O (azithromycin dihydrate) |
| Molecular Weight | 748.98 g/mol (azithromycin); 785.02 g/mol (azithromycin dihydrate) |
| Grade | Pharma Grade / API Grade |
| Appearance | White or almost white crystalline powder |
| Assay | 98.0% to 102.0% (HPLC, anhydrous basis) |
| Purity | ≥ 98.0% (HPLC) |
| Standard | USP/EP/BP/ChP |
| Solubility | Freely soluble in methanol, acetone, chloroform, ethanol; practically insoluble in water |
| Storage | Store in a cool, dry place, protected from light and moisture; 15-30°C |
| Shelf Life | 24 to 36 months when stored properly |
| Packaging | 25 kg fiber drum with double polyethylene bags |
| Therapeutic Class | Macrolide antibiotic |
| Route Of Administration | Oral and Injectable |
| Dosage Forms | Tablet, Capsule, Granule, Injection |
As an accredited Azithromycin for injection Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | |
| Shipping | |
| Storage |
Azithromycin dihydrate is the preferred solid-state form for immediate-release tablet manufacture because it exhibits lower hygroscopicity than the monohydrate and maintains crystallinity through aqueous wet granulation. In production-scale high-shear granulators with bowl capacities from 150 L to 600 L, the API is dry-mixed with microcrystalline cellulose, pregelatinized starch, and a small quantity of sodium lauryl sulfate as a wetting agent. The active load is commonly 250 mg or 500 mg per unit, equivalent to 45–60% w/w of the uncoated tablet core depending on the filler system. Compliance with USP <711> dissolution, USP <905> uniformity of dosage units, ICH Q3D elemental impurity limits, and the USP Azithromycin Tablets monograph is expected for global dossiers; residual solvent limits are additionally assessed under USP <467> against ICH Q3C classes. Wet granulation is preferred over direct compression because azithromycin dihydrate has poor flow and low bulk density. The granulation endpoint is controlled by impeller power consumption or torque rather than fixed time. Drying in a fluid-bed dryer to loss-on-drying ≤2.0% w/w prevents hydrolysis and preserves the dihydrate crystal habit. The dried granulate is milled through a 0.8–1.2 mm screen, blended with magnesium stearate at 0.5–1.0% w/w, and compacted on a rotary tablet press at 8–16 kN main compression force. Target hardness for 500 mg tablets is commonly 10–15 kp, with friability below 1.0% under USP <1216>. Film coating with a hydroxypropylmethylcellulose/PEG system is applied to 3–4% w/w weight gain to reduce bitter taste and improve swallowability. The principal processing failure observed on production lines is edge erosion and capping when granulate moisture content falls below 1.0% w/w; conversely, moisture above 2.5% w/w induces picking and sticking on upper punches. Terminal finished products include 250 mg and 500 mg film-coated tablets packed in Alu/Alu or PVC/PVDC blisters.
On capsule filling lines equipped with dosator or tamping-pin machines, azithromycin dihydrate is generally supplied as a pre-sieved granulate rather than a micronized powder. The primary differentiator from tablet production is the requirement for consistent bulk density and flow, because encapsulation weight variation is driven more by powder bed uniformity than by compression yield. A typical fill weight for a 250 mg capsule may range from 400 mg to 550 mg, placing the API fraction at 45–65% w/w in the filled powder. Pharmacopoeial compliance for capsules relies on the compendial Azithromycin Capsules monograph where adopted, plus USP <905> content uniformity, USP <711> dissolution, ICH Q3C residual solvent limits, and USP <467> residual solvent testing where required. Gelatine capsule shells also require compliance with 21 CFR 211.94 drug product container closure testing and local gelatin quality standards. The manufacturing route typically combines the API with lactose monohydrate or dicalcium phosphate dihydrate, maize starch, croscarmellose sodium, and magnesium stearate; the dry blend may be slugged and granulated if API content exceeds 50% w/w and the raw powder exhibits poor flow. In high-humidity environments beyond 60% RH, pre-conditioning of gelatine shells and controlled filling suites at 35–45% RH are required to prevent brittle shells and telescoping. Finished forms are hard capsules containing 250 mg azithromycin, typically packed in cold-form aluminium blisters for moisture-sensitive geographies.
Azithromycin powder for oral suspension is manufactured as a dry syrup granulate that is reconstituted with potable water at the point of dispensing. The formulation addition ratio is expressed as the amount of azithromycin dihydrate equivalent to 200 mg/5 mL or 100 mg/5 mL after reconstitution; dry syrup bottles may contain 300 mg, 600 mg, 900 mg, or 1200 mg total azithromycin in a powder fill weight of 15–60 g. In bulk dry syrup powders the API fraction is typically 2–5% w/w because sucrose or sorbitol dominates as the bulking sweetener; single-dose sachet granules may range from 10–25% w/w when the fill mass is 2–6 g for a 250 mg to 1 g dose. The production process uses wet granulation or sugar-sphere layering followed by drying to ≤1.5% w/w moisture and sieving to a target D90 ≤ 1,000 µm. Granule particle size directly determines reconstitution time and sedimentation ratio; if fines below 50 µm exceed 10% w/w, the powder forms a non-wetting raft on the water surface, while granules above 1,500 µm remain gritty and may clog oral syringes. Industry compliance is anchored to the Azithromycin for Oral Suspension USP monograph, USP <698> deliverable volume, USP <905> uniformity of dosage units where applicable, and 21 CFR 211.166 stability protocols defining post-reconstitution storage conditions. The API is not dissolved in the syrup because azithromycin has low aqueous solubility and a bitter taste; instead, xanthan gum or hydroxypropyl cellulose is added as a suspending agent, and sodium phosphate buffers adjust final pH to 8.5–10.0 after reconstitution to minimize soluble API and reduce taste perception. Terminal products include multi-dose dry syrup bottles for paediatric 100 mg/5 mL and 200 mg/5 mL strengths, as well as unit-dose sachets containing 250 mg, 500 mg, or 1 g granules dispersed in water immediately before administration.
Sterile injectable manufacturing of azithromycin imposes three process-control points that are not encountered in oral solid dosage lines: bioburden control of the incoming API, maintenance of a stable pH prior to sterile filtration, and a lyophilization cycle that avoids cake collapse. The reference product format supplies azithromycin dihydrate equivalent to 500 mg per 10 mL vial, together with anhydrous citric acid and sodium hydroxide as pH adjusters; the active compound represents approximately 85–90% w/w of the lyophilized cake mass. The manufacturing process begins with dissolution of the API in water for injection at 10–20°C, followed by pH adjustment and sterile filtration through a 0.22 µm polyvinylidene fluoride or polyethersulfone membrane. The filtered solution is filled into depyrogenated glass vials under EU Grade A conditions, partially stoppered, and loaded into a lyophilizer. The lyophilization cycle is designed to dry the citrate-buffered matrix while avoiding collapse: freezing is conducted to −40°C or lower, primary drying is held at shelf temperatures of −20°C to −10°C with chamber pressure in the range of 100–200 mTorr, and secondary drying is ramped to 30°C until residual moisture is ≤1.0% w/w. Freeze-drying microscopy is used in development to confirm the collapse temperature; if primary drying exceeds that temperature, microcollapse produces a shrunken cake with prolonged reconstitution time. The final cake is a white to off-white porous solid that dissolves within 3–5 minutes after addition of sterile water for injection to a concentration of 100 mg/mL. For intravenous administration, the reconstituted concentrate is diluted to 1.0–2.0 mg/mL in 0.9% sodium chloride injection or 5% dextrose injection; concentrations above 2.0 mg/mL are avoided due to local infusion-site reactions. Compliance requirements include USP <1>, USP <71> sterility, USP <85> bacterial endotoxins, USP <788> particulate matter in injections, USP <790> visible particulates, and EU GMP Annex 1 aseptic processing. The lyophilized product is not formulated for intramuscular or subcutaneous injection. Terminal finished products are single-dose vials of lyophilized powder for concentrate for solution for infusion, typically 500 mg per vial, for hospital use in respiratory and pelvic infections.
Competitive Azithromycin for injection Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8618136850665 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8618136850665
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Azithromycin for injection Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable is released under product model AZM-PG-10, with azithromycin base CAS 83905-01-5 and molecular formula C38H72N2O12, corresponding to an anhydrous base molecular weight of 748.98 g/mol. The material is a white to off-white crystalline powder and is manufactured under ICH Q7 active pharmaceutical ingredient GMP conditions. It is supplied in non-sterile low-endotoxin packaging intended for subsequent sterile-filtration processes, or as sterile lyophilized packaging with a validated sterility assurance level of 10−6 after aseptic processing. Compendial assay limits are controlled at 945–1030 µg/mg on the anhydrous basis, with water content 4.0–5.0% for the dihydrate. The product is intended solely for pharmaceutical manufacturing by qualified facilities and is not for direct patient administration.
The injectable grade applies tighter bioburden and bacterial endotoxin controls than oral-only material while retaining the same solid-state crystalline form. Table 1 lists release parameters for model AZM-PG-10 across solid oral and injectable applications. The limit for bacterial endotoxins is set at ≤0.50 EU/mg for injectable use under USP <85>, whereas oral-only material may be released with a higher endotoxin limit where justified by the finished-product route of administration. Elemental impurities are controlled by ICH Q3D Option 1, and residual solvent testing follows USP <467>; acetone, ethanol, and isopropanol are controlled as Class 3 solvents at ≤5000 ppm unless otherwise specified in the batch certificate.
| Parameter | Acceptance criterion | Method or standard |
|---|---|---|
| Appearance | White to off-white crystalline powder | Visual inspection |
| Assay, anhydrous basis | 945–1030 µg/mg | HPLC per USP azithromycin monograph |
| Water content, dihydrate | 4.0–5.0% | Karl Fischer, USP <921> Ic |
| Residue on ignition | ≤0.1% | USP <281> |
| Bacterial endotoxins, injectable grade | ≤0.50 EU/mg | USP <85> |
| Microbial enumeration, non-sterile grade | ≤100 CFU/g; absence of Escherichia coli, Salmonella | USP <61>, USP <62> |
| Residual solvents | Class 3 solvents ≤5000 ppm | USP <467> Option A |
| Particle size, solid oral | D90 ≤100 µm | Laser diffraction, USP <429> |
| Particle size, suspension | D50 5–15 µm; D90 ≤35 µm | Laser diffraction, USP <429> |
Micromeritic behavior of the API determines the granulation route. The crystalline dihydrate shows a Hausner ratio above 1.35 and a Carr index above 25% in as-supplied lot samples, indicating poor free-flow characteristics. Roller compaction with 0.5–1.0% magnesium stearate or high-shear wet granulation at impeller speeds of 150–250 rpm and chopper speeds of 1500 rpm is required for tablet compression. Direct compression is not recommended because segregation and weight variation can exceed 2.0% RSD when run at press speeds above 60 rpm, compromising uniformity of dosage units under USP <905>. For dry granulation, slugging or roller compaction should maintain material temperature below 40°C; temperatures above 45°C may release lattice water and increase amorphous content, which can shift dissolution profiles under USP <711>. For capsule filling, milled API with D90 ≤100 µm is blended with directly compressible lactose monohydrate and croscarmellose sodium at 2–4%; the blend is conditioned to 35–45% RH before encapsulation to avoid sticking and weight drift.
Sterile injectable manufacturing of azithromycin requires a low-endotoxin API with controlled particle morphology because the active ingredient has poor aqueous solubility at neutral pH. Injection-grade material is dissolved in a pH-adjusted vehicle and sterile-filtered through a 0.22 µm membrane before filling. The filtered solution is lyophilized to a cake that is reconstituted to 100 mg/mL with sterile water for injection, followed by dilution to 1–2 mg/mL in 0.9% sodium chloride or 5% dextrose for intravenous infusion. The lyophilization cycle must remain below the measured collapse temperature of the formulated solution; published data for this specific azithromycin formulation is limited, so thermal characterization by freeze-drying microscopy is required during process development. Primary drying shelf temperatures are typically evaluated between −30°C and −20°C. Sterile API supplied as a lyophilized powder is tested for sterility according to USP <71> and container–closure integrity according to USP <1207>. Gamma irradiation is not recommended unless forced-degradation studies demonstrate acceptable impurity profiles under ICH Q1A(R2).
Oral suspension and granule presentations require particle-size control because dissolution rate and mouthfeel are sensitive to D90. When the API is micronized to D50 5–15 µm, the dispersed suspension exhibits pseudoplastic flow at shear rates of 10–100 s−1; excessive micronization below D50 3 µm increases electrostatic charging and reduces blend uniformity. Taste masking with ethylcellulose or methacrylate copolymers at 10–20% polymer weight gain is applied in granule formulations because the dimethylamino group contributes bitter taste. Granule drying is conducted at inlet air temperature ≤50°C and product moisture 2.0–4.0%; overdrying below 1.5% moisture increases friability and leads to capping during tablet compression. These processing limits are derived from lot-dependent compressibility data and should be transferred with process analytical technology for real-time release.
The API is supplied double polyethylene-lined in fiber drums or in sterile glass vials with rubber stoppers for injectable grade. Stability testing under ICH Q1A(R2) at 25°C/60% RH and 40°C/75% RH is reported on the certificate of analysis; the API should be protected from moisture above 60% RH to avoid hydrate transitions that can alter dissolution behavior. Degradation products are controlled by HPLC with total impurities ≤2.0%, any unspecified impurity ≤0.10%, and specific limits assigned to known degradants including descladinose azithromycin and azithromycin N-oxide. The API should not be exposed to strongly acidic granulating fluids below pH 2 because acid-catalyzed hydrolysis of the cladinose sugar is a principal degradative pathway. Wet granulation binder solutions should be buffered to pH 6–7 where possible. Elemental impurity statements are provided under USP <232> and USP <233>; no Class 1 or Class 2A elemental impurities are intentionally introduced during manufacture.
Compared with erythromycin and clarithromycin, azithromycin is a 15-membered azalide macrolide rather than a 14-membered macrolide. This structural difference reduces internal hemiketal formation and confers acid stability, so oral dosage forms do not require enteric coating to protect the active core. The tissue half-life of azithromycin is approximately 68 h, compared with 3–4 h for clarithromycin and 1.5 h for erythromycin. The longer half-life supports once-daily administration in finished products and requires extended washout periods in bioequivalence studies. Azithromycin is a weak inhibitor of CYP3A4, whereas clarithromycin is a strong inhibitor and erythromycin is a moderate inhibitor; this difference reduces the risk of certain drug–drug interactions in the clinical use of the finished dosage form. Table 2 summarizes the manufacturing-relevant distinctions among these macrolides.
| Attribute | Azithromycin | Clarithromycin | Erythromycin |
|---|---|---|---|
| Ring structure | 15-membered azalide | 14-membered macrolide | 14-membered macrolide |
| Acid stability | Stable; no enteric coating required | Acid stable | Acid labile; enteric coating or ester prodrug required |
| Elimination half-life | ~68 h | ~3–4 h | ~1.5 h |
| Oral bioavailability | ~37% | ~50% | ~25% |
| Dosing frequency | Once daily | Twice daily | Four times daily |
| CYP3A4 inhibition | Weak | Strong | Moderate |
For solid oral dosage forms, the product is supplied with particle-size and moisture specifications matched to the intended granulation process. Unlike non-pharma azithromycin sources, the pharma grade includes cGMP batch documentation, residual solvent statements, elemental impurity data, and stability data under ICH Q1A(R2). Handling of micronized azithromycin should be performed in an ISO 14644-1 Class 8 downflow booth with local exhaust velocity of approximately 0.5 m/s. Occupational exposure limits for azithromycin are not harmonized globally; published regulatory occupational exposure limits for this specific macrolide are limited, so internal limits and qualified industrial hygiene monitoring are required. Dust explosion prevention should follow ATEX 2014/34/EU and NFPA 654. Milling and micronization equipment must be grounded, and inert handling should be used for micronized powder conveying at rates above 100 kg/h because published minimum ignition energy data for azithromycin dust are limited.
