INDICATIONS AND USAGE Nitroglycerin in 5% Dextrose Injection is indicated for treatment of peri-operative hypertension; for control of heart failure in the setting of acute myocardial infarction; for treatment of angina pectoris in patients who have not responded to sublingual nitroglycerin and ß-blockers; and for induction of intraoperative hypotension.

WARNINGS Use of PVC (polyvinyl chloride) tubing in infusion sets may lead to loss of active ingredient due to adsorption of nitroglycerin to PVC tubing, therefore dosage is affected (see Dosage and Administration ).

Nitroglycerin adsorption by PVC tubing is increased when the tubing is long, the flow rates are low, and the nitroglycerin concentration of the solution is high.

The delivered fraction of the solution's original nitroglycerin content has been 20-60% in published studies using PVC tubing; the fraction varies with time during a single infusion, and no simple correction factor can be used.

PVC tubing has been used in most published studies of intravenous nitroglycerin, but the reported doses have been calculated by simply multiplying the flow rate of the solution by the solution's original concentration of nitroglycerin.

The actual doses delivered have been less, sometimes much less, than those reported.

Relatively non-adsorptive intravenous administration sets are available.

If intravenous nitroglycerin is administered through non-adsorptive tubing, doses based upon published reports will generally be too high.

Some in-line intravenous filters also adsorb nitroglycerin; these filters should be avoided.

Solutions containing dextrose without electrolytes should not be administered through the same administration set as blood, as this may result in pseudoagglutination or hemolysis.

The intravenous administration of solutions may cause fluid overloading resulting in dilution of serum electrolyte concentrations, overhydration and congested states of pulmonary edema.

The risk of dilutional states is inversely proportional to the electrolyte concentrations of the injections.

The risk of solute overload causing congested states with peripheral and pulmonary edema is directly proportional to the electrolyte concentration of the injections.

ADVERSE REACTIONS Adverse reactions to nitroglycerin are generally dose-related and almost all of these reactions are the result of nitroglycerin's activity as a vasodilator.

Headache, which may be severe, is the most commonly reported side effect.

Headache may be recurrent with each daily dose, especially at higher doses.

Transient episodes of lightheadedness, occasionally related to blood pressure changes, may also occur.

Hypotension occurs infrequently, but in some patients it may be severe enough to warrant discontinuation of therapy.

Syncope, crescendo angina, and rebound hypertension have been reported but are uncommon.

Allergic reactions to nitroglycerin are also uncommon, and the great majority of those reported have been cases of contact dermatitis or fixed drug eruptions in patients receiving nitroglycerin in ointments or patches.

There have been a few reports of genuine anaphylactoid reactions, and these reactions can probably occur in patients receiving nitroglycerin by any route.

Extremely rarely, ordinary doses of organic nitrates have caused methemoglobinemia in normal-seeming patients.

Methemoglobinemia is so infrequent at these doses that further discussion of its diagnosis and treatment is deferred (see Overdosage ).

Dyspnea has also been reported.

Data are not available to allow estimation of the frequency of adverse reactions during treatment with Nitroglycerin in 5% Dextrose Injection.