Scope note: Ceftazidime as a sterile pharma-grade API is not converted into tablet, capsule, or granule dosage forms because the beta-lactam ring and free carboxylic acid are hydrolyzed in gastric pH, resulting in negligible oral bioavailability. Downstream applications are therefore confined to sterile injectable and sterile compounding routes: single-dose dry-powder vials, continuous intravenous infusion devices, extemporaneous ophthalmic solutions, peritoneal dialysate admixtures, and pharmacy bulk partition into patient-specific parenteral units.

Why Sterile Ceftazidime Powder Cannot Be Terminally Sterilised

Sterile manufacture of ceftazidime for injection excludes terminal steam sterilisation because the beta-lactam ring hydrolyzes under saturated steam conditions at 121°C; the resulting degradation products lack antimicrobial activity. Ceftazidime pentahydrate is therefore handled as a sterile dry powder produced by aseptic crystallisation, particle size reduction, blending with sterile sodium carbonate, and filling into Type I borosilicate glass vials. The formulation addition ratio is 1 g ceftazidime activity to 118 mg sodium carbonate for the 1 g vial, 236 mg for the 2 g vial, and 708 mg for the 6 g pharmacy bulk package. The sodium carbonate functions as an alkalizing and solubilizing excipient upon reconstitution and contributes approximately 2.3 mEq sodium per gram of ceftazidime activity. The downstream production process includes vial washing, dry-heat depyrogenation, aseptic powder filling under ISO Class 5 unidirectional airflow as defined by ISO 14644-1:2015, stoppering, and crimp capping in a restricted access barrier system with dehumidified supply air. Compliance is governed by the Ceftazidime for Injection USP monograph, USP <71> sterility, USP <85> bacterial endotoxin, USP <788> particulate matter in injection, 21 CFR 211.94 container closure system requirements, and EU GMP Annex 1 for sterile manufacturing. The terminal finished product is a single-dose glass vial of ceftazidime for injection in 1 g, 2 g, or 6 g activity, intended for reconstitution before intravenous or intramuscular administration. The main operational boundary is moisture ingress during filling: exposure of the dry powder to uncontrolled humidity initiates surface hydrolysis, visible powder clumping, and a shift in reconstituted solution pH. Residual moisture acceptance criteria are product-specific and are controlled by the API manufacturer’s certificate of analysis rather than by a single universal pharmacopoeial value.

For outpatient antimicrobial therapy and severe Pseudomonas aeruginosa infection where prolonged beta-lactam exposure is clinically indicated, ceftazidime is compounded into elastomeric continuous-infusion devices. The dry powder is manipulated in an ISO Class 5 compounding aseptic isolator: the 6 g vial is brought to room temperature, the rubber closure is disinfected with sterile 70% isopropyl alcohol, and 26 mL Sterile Water for Injection is introduced to yield a nominal 200 mg/mL concentrate. This concentrate is transferred to an elastomeric pump reservoir and diluted with 0.9% sodium chloride injection to a working concentration of 25 mg/mL, corresponding to 6 g ceftazidime in 240 mL. The sodium carbonate component contributes 13.8 mEq sodium per 6 g dose, a factor that must be quantified in sodium-restricted patients. The downstream production process includes sterile syringe transfer, removal of air from the elastomeric reservoir, and priming of the pump at a nominal flow rate of 10 mL/h to deliver the total volume over 24 h. Compounding compliance falls under USP <797>, and the elastomeric pump should be operated within the manufacturer’s labelled flow-rate accuracy and back-pressure limits. The terminal finished product is a wearable elastomeric infusor containing 240 mL ceftazidime 25 mg/mL in 0.9% sodium chloride. The critical process conflict is pH-dependent hydrolytic instability: ceftazidime in aqueous solution degrades more rapidly as pH rises, and above pH 8 the beta-lactam ring hydrolysis rate can reduce active content before the end of the infusion. The final solution after dilution should remain within the reconstituted pH range of 5.0 to 7.5. Incompatibility with aminoglycosides is operationally significant; ceftazidime should not be admixed with gentamicin, tobramycin, or amikacin in the same pump chamber or connected line without an intervening flush because mutual inactivation and particulate formation have been documented. Published data for ceftazidime 25 mg/mL in 0.9% sodium chloride in elastomeric devices indicate a 24 h room-temperature stability window at 25°C; body-surface temperatures above 25°C, longer dwell times, or alternative diluents require site-specific stability verification under USP <797> because published data for those configurations is limited.

Fortified Ophthalmic Compounding from Sterile Dry Powder

When ceftazidime dry powder is used for topical ophthalmic treatment of bacterial keratitis, the sterile injectable starting material is compounded into a preservative-free fortified solution because no licensed commercial ophthalmic ceftazidime is available. The formulation addition ratio is a final ceftazidime concentration of 50 mg/mL, commonly prepared by reconstituting a 1 g vial with 10 mL Sterile Water for Injection to obtain an intermediate concentration of 100 mg/mL, then diluting to a final volume of 20 mL with preservative-free ophthalmic irrigating solution or balanced salt solution. The downstream production process is performed in an ISO Class 5 laminar-airflow hood under USP <797> low-risk compounded sterile preparation conditions; the reconstituted solution is drawn into a sterile syringe, transferred to a sterile amber ophthalmic dropper bottle, and used without terminal sterilisation. Because the preparation is intended for the eye, particulate matter is controlled according to USP <789>; sterility of the starting vial lot is verified by supplier certificate and aseptic technique rather than post-compounding sterility testing of every ophthalmic batch. The terminal finished product is a preservative-free fortified ophthalmic solution, 50 mg/mL, packaged in an amber dropper bottle and labelled with a patient-specific beyond-use date. Published data for the physicochemical stability of ceftazidime 50 mg/mL in ophthalmic vehicles is limited; several public hospital compounding protocols assign refrigerated storage between 2°C and 8°C for up to 7 days, but stability beyond this should be confirmed by validated high-performance liquid chromatography because the solution is preservative-free and sterility cannot be assumed after the first withdrawal.

Intraperitoneal administration of ceftazidime for peritoneal dialysis-associated peritonitis requires the dry sterile API to be dissolved and admixed into dialysate bags under aseptic conditions immediately before use. The formulation addition ratio depends on the dosing strategy: continuous intraperitoneal dosing uses a ceftazidime concentration of 125 mg/L to 250 mg/L in each dialysate bag, while intermittent dosing uses 1 g ceftazidime added to one 2 L bag once daily during a long dwell of at least 6 h. The downstream production process starts with reconstitution of a 1 g vial in 10 mL Sterile Water for Injection; the required volume is then injected through the dialysate bag additive port in an ISO Class 5 hood, and the bag is mixed by gentle inversion rather than shaking to avoid foam formation and possible precipitation. The compliance framework is the International Society for Peritoneal Dialysis peritonitis treatment guideline, USP <797> for sterile compounding, and the hospital’s dialysis fluid sterility policy; the receiving container is a closed, single-use, sterile dialysate bag of the type used for continuous ambulatory peritoneal dialysis or automated peritoneal dialysis. The terminal finished product is a ready-to-use intraperitoneal dialysate bag, such as a 2 L glucose-based dialysate bag containing 1 g ceftazidime, intended for immediate connection to the patient’s peritoneal catheter. Published data for ceftazidime stability in icodextrin-based dialysate is limited; in the absence of a validated stability study for that specific carrier, the admixture should be prepared in glucose-based dialysate and administered without delay. The main operational boundary is that the admixture must not be stored beyond the shortest of the drug-specific stability window and the dialysate bag label storage limit; because ceftazidime in solution is heat-labile, bags that have warmed to body temperature during patient transport are assigned a shorter beyond-use date than refrigerated bags.

If a Pharmacy Bulk Package Is Partitioned, Aseptic Handling Thresholds Change

When the 6 g ceftazidime pharmacy bulk package is used in a hospital sterile compounding unit, the downstream process is not reconstitution for a single patient but sequential partition of the reconstituted drug into multiple patient-specific intravenous units. The formulation addition ratio remains 1 g ceftazidime activity per 118 mg sodium carbonate, so the 6 g package contains 708 mg sodium carbonate. The production process requires the pharmacy bulk package to be accessed only in an ISO Class 5 hood under USP <797> Category 2 compounding conditions; the rubber closure is disinfected with sterile 70% isopropyl alcohol, and each dose is withdrawn with a separate sterile syringe to reduce cross-contamination risk. The terminal finished product is a series of individually labelled intravenous admixture bags prepared from the same bulk source, typically containing 1 g or 2 g ceftazidime per 50 mL to 100 mL of compatible diluent. The pharmacy bulk package is not intended for direct patient administration and must be discarded if the closure integrity is compromised, if the vial is removed from the controlled aseptic area, or if the maximum in-use time specified in the facility’s USP <797> Category 2 policy is exceeded. Published data for extended hold times of reconstituted ceftazidime 200 mg/mL in partially used pharmacy bulk packages is limited; therefore the most conservative facility-specific beyond-use allocation is applied when the same vial is used to prepare multiple scheduled doses.