ISOSULFAN BLUE: 68 Adverse Event Reports & Safety Profile

The chemical name of isosulfan blue is N-[4-[[4-(diethylamino)phenyl] (2,5-disulfophenyl) methylene]-2,5-cyclohexadien-1-ylidene]-N-ethylethanaminium hydroxide, inner salt, sodium salt. Isosulfan blue is a greenish blue color hygroscopic powder. Its structural formula is: Isosulfan blue injection 1% is a sterile, non-pyrogenic, aqueous dark blue color solution for subcutaneous administration. Phosphate buffer in water for injection is added in sufficient quantity to yield a final pH of 6.8 to 7.4. Each mL of solution contains 10 mg isosulfan blue, 6.6 mg sodium monohydrogen phosphate and 2.7 mg potassium dihydrogen phosphate. The solution contains no preservative. Isosulfan blue injection 1% is a contrast agent for the delineation of lymphatic vessels.

Isosulfan Blue

Chemical structure

AND USAGE Isosulfan Blue Injection 1% upon subcutaneous administration, delineates the lymphatic vessels draining the region of injection. It is an adjunct to lymphography in: primary and secondary lymphedema of the extremities; chyluria, chylous ascites or chylothorax; lymph node involvement by primary or secondary neoplasm; lymph node response to therapeutic modalities ( 1.1 ).

1.1 Lymphatic Vessel Delineation Isosulfan Blue Injection 1% upon subcutaneous administration, delineates lymphatic vessels draining the region of injection. It is an adjunct to lymphography in: primary and secondary lymphedema of the extremities; chyluria, chylous ascites or chylothorax; lymph node involvement by primary or secondary neoplasm; and lymph node response to therapeutic modalities.

AND ADMINISTRATION Isosulfan blue injection 1% is to be administered subcutaneously, one-half (1/2) mL into three (3) interdigital spaces of each extremity per study. A maximum dose of 3 mL (30 mg) isosulfan blue is, therefore, injected ( 2.1 ).

2.1 Subcutaneous administration Isosulfan blue injection 1% is to be administered subcutaneously, one-half (1/2) mL into three (3) interdigital spaces of each extremity per study. A maximum dose of 3 mL (30 mg) isosulfan blue is, therefore, injected. Discard unused portion.

Isosulfan blue injection 1% is contraindicated in those individuals with known hypersensitivity to triphenylmethane or related compounds. Hypersensitivity to triphenylmethane or related compounds ( 4 ).

REACTIONS Hypersensitivity Reactions : Hypersensitivity reactions occurring approximately 2% of patients and include life-threatening anaphylactic reactions with respiratory distress, shock, angioedema, urticaria, pruritus. A death has been reported following IV administration of a similar compound ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Meitheal Pharmaceuticals Inc. at 1-844-824-8426 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Postmarketing Experience Hypersensitivity Reactions: Case series report an overall incidence of hypersensitivity reactions in approximately 2% of patients. Life-threatening anaphylactic reactions have occurred. Manifestations include respiratory distress, shock, angioedema, urticaria, pruritus. A death has been reported following administration of a similar compound employed to estimate the depth of a severe burn. Reactions are more likely to occur in patients with a personal or family history of bronchial asthma, significant allergies, drug reactions or previous reactions to triphenylmethane dyes <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5 )]</span> . Laboratory tests: Isosulfan blue 1% interferes with measurements of oxygen saturation by pulse oximetry and of methemoglobin by gas analyzer <span class="opacity-50 text-xs">[see Warnings and Precautions ( 5 )]</span> . Skin: Transient or long-term (tattooing) blue coloration.

AND PRECAUTIONS

• Life threatening anaphylactic reactions have occurred after isosulfan blue injection 1% administration. Monitor patients closely for at least 60 minutes after administration of isosulfan blue injection 1% ( 5.1 ).
• The admixture of isosulfan blue injection 1% with local anesthetics results in an immediate precipitation of 4% to 9% drug complex. Use a separate syringe for anesthetics ( 5.2 ).
• Isosulfan blue injection 1% interferes with measurements in peripheral blood pulse oximetry. Arterial blood gas analysis may be needed ( 5.3 ).

5.1 Hypersensitivity Reactions Life threatening anaphylactic reactions (respiratory distress, shock, angioedema) have occurred after isosulfan blue injection 1% administration. Reactions are more likely to occur in patients with a history of bronchial asthma, allergies, drug reactions or previous reactions to tri-phenylmethane dyes. Monitor patients closely for at least 60 minutes after administration of isosulfan blue injection 1%. Trained personnel should be available to administer emergency care including resuscitation.

5.2 Precipitation of Isosulfan Blue Injection 1% by Lidocaine The admixture of isosulfan blue injection 1% (with local anesthetics (i.e. lidocaine)) in the same syringe results in an immediate precipitation of 4% to 9% drug complex. Use a separate syringe to administer a local anesthetic.

5.3 Interference with Oxygen Saturation and Methemoglobin Measurements Isosulfan blue injection 1% interferes with measurements of oxygen saturation in peripheral blood by pulse oximetry and can cause falsely low readings. The interference effect is maximal at 30 minutes and minimal generally by 4 hours after administration. Arterial blood gas analysis may be needed to verify decreased arterial partial pressure of oxygen. Isosulfan blue injection 1% may also cause falsely elevated readings of methemoglobin by arterial blood gas analyzer. Therefore, cooximetry may be needed to verify methemoglobin level.

INTERACTIONS No drug interactions have been identified with isosulfan blue injection 1%. No drug interactions have been identified for isosulfan blue injection 1% ( 7 ).