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Fortaz Dosage

Generic name: CEFTAZIDIME 100mg in 1mL
Dosage form: injection, powder, for solution

Medically reviewed on July 28, 2017.


The usual adult dosage is 1 gram administered intravenously or intramuscularly every 8 to 12 hours. The dosage and route should be determined by the susceptibility of the causative organisms, the severity of infection, and the condition and renal function of the patient.

The guidelines for dosage of FORTAZ are listed in Table 5. The following dosage schedule is recommended.

Table 5. Recommended Dosage Schedule
Although clinical improvement has been shown, bacteriologic cures cannot be expected in patients with chronic respiratory disease and cystic fibrosis.
The higher dose should be reserved for immunocompromised pediatric patients or pediatric patients with cystic fibrosis or meningitis.




Usual recommended dosage

1 gram intravenous or intramuscular

every 8 to 12 hours

Uncomplicated urinary tract infections

250 mg intravenous or intramuscular

every 12 hours

Bone and joint infections

2 grams intravenous

every 12 hours

Complicated urinary tract infections

500 mg intravenous or intramuscular

every 8 to 12 hours

Uncomplicated pneumonia; mild skin and skin-structure infections

500 mg to 1 gram intravenous or intramuscular

every 8 hours

Serious gynecologic and intra-abdominal infections

2 grams intravenous

every 8 hours


2 grams intravenous

every 8 hours

Very severe life-threatening infections, especially in immunocompromised patients

2 grams intravenous

every 8 hours

Lung infections caused by Pseudomonas spp. in patients with cystic fibrosis with normal renal function*

30 to 50 mg/kg intravenous to a maximum of 6 grams per day

every 8 hours

Neonates (0-4 weeks)

30 mg/kg intravenous

every 12 hours

Infants and children

(1 month-12 years)

30 to 50 mg/kg intravenous to a maximum of 6 grams per day

every 8 hours

Impaired Hepatic Function

No adjustment in dosage is required for patients with hepatic dysfunction.

Impaired Renal Function

Ceftazidime is excreted by the kidneys, almost exclusively by glomerular filtration. Therefore, in patients with impaired renal function (glomerular filtration rate [GFR] <50 mL/min), it is recommended that the dosage of ceftazidime be reduced to compensate for its slower excretion. In patients with suspected renal insufficiency, an initial loading dose of 1 gram of FORTAZ may be given. An estimate of GFR should be made to determine the appropriate maintenance dosage. The recommended dosage is presented in Table 6.

Table 6. Recommended Maintenance Dosages of FORTAZ in Renal Insufficiency


Creatinine Clearance (mL/min)

Recommended Unit Dose


Frequency of Dosing


1 gram

every 12 hours


1 gram

every 24 hours


500 mg

every 24 hours

less than 5

500 mg

every 48 hours

When only serum creatinine is available, the following formula (Cockcroft's equation)5 may be used to estimate creatinine clearance. The serum creatinine should represent a steady state of renal function:

Males: Creatinine clearance (mL/min) =

Weight (kg) x (140 - age)

72 x serum creatinine (mg/dL)

Females: 0.85 x male value

In patients with severe infections who would normally receive 6 grams of FORTAZ daily were it not for renal insufficiency, the unit dose given in the table above may be increased by 50% or the dosing frequency may be increased appropriately. Further dosing should be determined by therapeutic monitoring, severity of the infection, and susceptibility of the causative organism.

In pediatric patients as for adults, the creatinine clearance should be adjusted for body surface area or lean body mass, and the dosing frequency should be reduced in cases of renal insufficiency.

In patients undergoing hemodialysis, a loading dose of 1 gram is recommended, followed by 1 gram after each hemodialysis period.

FORTAZ can also be used in patients undergoing intraperitoneal dialysis and continuous ambulatory peritoneal dialysis. In such patients, a loading dose of 1 gram of FORTAZ may be given, followed by 500 mg every 24 hours. In addition to IV use, FORTAZ can be incorporated in the dialysis fluid at a concentration of 250 mg for 2 L of dialysis fluid.

Note: Generally FORTAZ should be continued for 2 days after the signs and symptoms of infection have disappeared, but in complicated infections longer therapy may be required.


FORTAZ may be given intravenously or by deep IM injection into a large muscle mass such as the upper outer quadrant of the gluteus maximus or lateral part of the thigh. Intra-arterial administration should be avoided (see PRECAUTIONS).

Intramuscular Administration

For IM administration, FORTAZ should be constituted with one of the following diluents: Sterile Water for Injection, Bacteriostatic Water for Injection, or 0.5% or 1% Lidocaine Hydrochloride Injection. Refer to Table 7.

Intravenous Administration

The IV route is preferable for patients with bacterial septicemia, bacterial meningitis, peritonitis, or other severe or life-threatening infections, or for patients who may be poor risks because of lowered resistance resulting from such debilitating conditions as malnutrition, trauma, surgery, diabetes, heart failure, or malignancy, particularly if shock is present or pending.

For direct intermittent IV administration, constitute FORTAZ as directed in Table 7 with Sterile Water for Injection. Slowly inject directly into the vein over a period of 3 to 5 minutes or give through the tubing of an administration set while the patient is also receiving one of the compatible IV fluids (see COMPATIBILITY AND STABILITY).

For IV infusion, constitute the 500-mg, 1-gram, or 2-gram vial and add an appropriate quantity of the resulting solution to an IV container with one of the compatible IV fluids listed under the COMPATIBILITY AND STABILITY section.

Intermittent IV infusion with a Y-type administration set can be accomplished with compatible solutions. However, during infusion of a solution containing ceftazidime, it is desirable to discontinue the other solution.

TwistVialTM vials are to be constituted only with 50 or 100 mL of 5% Dextrose Injection, 0.9% Sodium Chloride Injection, or 0.45% Sodium Chloride Injection in compatible flexible diluent containers (see Instructions for Constitution). TwistVialTM vials that have been joined to compatible diluent containers and activated to dissolve the drug are stable for 12 hours at room temperature or for 3 days under refrigeration. Joined vials that have not been activated may be used within a 14-day period; this period corresponds to that for use of compatible diluent containers following removal of the outer packaging (overwrap).

Freezing solutions of FORTAZ is not recommended.

Table 7. Preparation of Solutions of FORTAZ
To obtain a dose of 500 mg, withdraw 5 mL from the vial following reconstitution.
To obtain a dose of 1 g, withdraw 10 mL from the vial following reconstitution.
To obtain a dose of 2 g, withdraw 11.5 mL from the vial following reconstitution.


Amount of Diluent to be Added


Approximate Available Volume


Approximate Ceftazidime Concentration



500-mg vial




1-gram vial





500-mg vial




1-gram vial




2-gram vial




All vials of FORTAZ as supplied are under reduced pressure. When FORTAZ is dissolved, carbon dioxide is released and a positive pressure develops. For ease of use please follow the recommended techniques of constitution described on the detachable Instructions for Constitution section of this insert.

Solutions of FORTAZ, like those of most beta-lactam antibacterial drugs, should not be added to solutions of aminoglycoside antibacterial drugs because of potential interaction.

However, if concurrent therapy with FORTAZ and an aminoglycoside is indicated, each of these antibacterial drugs can be administered separately to the same patient.

Directions for Use of FORTAZ Frozen in Galaxy® Plastic Containers

FORTAZ supplied as a frozen, sterile, iso-osmotic, nonpyrogenic solution in plastic containers is to be administered after thawing either as a continuous or intermittent IV infusion. The thawed solution is stable for 8 hours at room temperature or for 3 days if stored under refrigeration. Do not refreeze.

Thaw container at room temperature (25°C) or under refrigeration (5°C). Do not force thaw by immersion in water baths or by microwave irradiation. Components of the solution may precipitate in the frozen state and will dissolve upon reaching room temperature with little or no agitation. Potency is not affected. Mix after solution has reached room temperature. Check for minute leaks by squeezing bag firmly. Discard bag if leaks are found as sterility may be impaired. Do not add supplementary medication. Do not use unless solution is clear and seal is intact.

Use sterile equipment.


Do not use plastic containers in series connections. Such use could result in air embolism due to residual air being drawn from the primary container before administration of the fluid from the secondary container is complete.

Preparation for Administration

Suspend container from eyelet support.
Remove protector from outlet port at bottom of container.
Attach administration set. Refer to complete directions accompanying set.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.