IV Dilution &
Medication Reference

Nitroglycerin

Usual Diluents

Standard Dilutions [Amount of drug] [Infusion volume] [Infusion rate]

Stability / Miscellaneous

Calculation of drip rate (50 mg/250 ml) ml/hr = mcg/min x 0.3
(eg 5 mcg/min=@ 2ml/hr ; 20mcg/min = 6 ml/hr etc.)

DOSAGE AND ADMINISTRATION
NOT FOR DIRECT INTRAVENOUS INJECTION. NITROGLYCERIN INJECTION, USP IS A CONCENTRATED, POTENT DRUG WHICH MUST BE DILUTED IN 5% DEXTROSE INJECTION, USP OR 0.9% SODIUM CHLORIDE INJECTION, USP, PRIOR TO ITS INFUSION. NITROGLYCERIN SHOULD NOT BE MIXED WITH OTHER DRUGS.

1. Initial Dilution: Aseptically transfer the desired amount of Nitroglycerin Injection, USP (as noted in the table below) into a glass I.V. bottle containing the stated volume of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP and mix well. This yields a final concentration of 50 mcg/mL to 400 mcg/mL. Diluting 5 mg nitroglycerin injection into 100 mL will also yield a final concentration of 50 mcg/mL.

2. Maintenance Dilution: It is important to consider the fluid requirements of the patient as well as the expected duration of infusion in selecting the appropriate dilution of nitroglycerin injection.

After the initial dosage titration, the concentration of the admixture may be increased, if necessary, to limit fluids given to the patient. The concentration of the infusion solution should not exceed 400 mcg/mL of nitroglycerin. See chart.

Note: If the concentration is adjusted, it is imperative to flush or replace the infusion set before a new concentration is utilized. If the set is not flushed or replaced, it could take minutes to hours, depending upon the flow rate and the dead space of the set, for the concentration to reach the patient.

Invert the glass parenteral bottle several times to assure uniform dilution of nitroglycerin.

Dosage is affected by the type of container and administration set used.

Although the usual starting adult dose range reported in clinical studies was 25 mcg/min or more, these studies used PVC administration sets. THE USE OF NONABSORBING TUBING WILL RESULT IN THE NEED FOR REDUCED DOSES.

If a peristaltic action infusion pump is used, an appropriate administration set should be selected with a drip chamber that delivers approximately 60 microdrops/mL. The dilution and administration tables below may be used to calculate the nitroglycerin dilution and flow rate in microdrops/minute to achieve the desired nitroglycerin injection administration rate.

If a volumetric infusion pump is used, the dilution and administration table below may still be used; however, flow rate will be determined directly by the infusion pump independent of the drop size of the drop chambers. Thus, the reference to "microdrops/min" is not applicable, and the corresponding flow rate in the mL/hr should be used to determine pump settings.

The dosage for nitroglycerin should initially be 5 mcg/min delivered through an infusion pump capable of exact and constant delivery of the drug. Subsequent titration must be adjusted to the clinical situation, with dose increments becoming more cautious as partial response is seen. Initial titration should be in 5 mcg/min increments, with increases every 3 to 5 minutes until some response is noted. If no response is seen at 20 mcg/min, increments of 10 and later 20 mcg/min can be used. Once a partial blood pressure response is observed, the dose increase should be reduced and the interval between increments should be lengthened. [maximum dose: 400 mcg/minute]

Patients with normal or low left ventricular filling pressure or pulmonary capillary wedge pressure (e.g., angina patients without other complications) may be hypersensitive to the effects of nitroglycerin and may respond fully to doses as small as 5 mcg/min. These patients require especially careful titration and monitoring.

There is no fixed optimum dose of nitroglycerin. Due to variations in the responsiveness of individual patients to the drug, each patient must be titrated to the desired level of hemodynamic function. Therefore, continuous monitoring of physiologic parameters (i.e., blood pressure and heart rate in all patients, other measurements such as pulmonary capillary wedge pressure, as appropriate) MUST be performed to achieve the correct dose. Adequate systemic blood pressure and coronary perfusion pressure must be maintained.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Discard unused portion.

HOW SUPPLIED
List No. Container Size Nitroglycerin Content
4107 Single-dose Fliptop Vial 5 mL 25 mg (5 mg/mL)
4104 Single-dose Fliptop Vial 10 mL 50 mg (5 mg/mL)

Store at 20 to 25°C (68 to 77°F). [See USP Controlled Room Temperature.] Do not permit to freeze.

Protect from light by retaining product in carton until ready to use.

©Hospira 2004 EN-0569
HOSPIRA, INC., LAKE FOREST, IL 60045 USA

Source: [package insert]

Stability: Source [ Lexi-drugs]: "Nitroglycerin diluted in D5W or NS in glass containers is physically and chemically stable for 48 hours at room temperature and 7 days under refrigeration; in D5W or NS in Excell®/PAB® containers is physically and chemically stable for 24 hours at room temperature and 14 days under refrigeration"