The chemical structure of fluorescein sodium is represented as:
NaO O O
Empirical formula: C20H10Na2O5 Molecular weight: 376.27 Chemical name: Disodium 2-(6-oxido-3-oxo-3H- xanthen-9-yl) benzoate CAS Registry Number: 518-47-8 (fluorescein sodium) 2321-07-5 (fluorescein)
FLUORESCITE injection 10% is a sterile solution for use intravenously as a diagnostic aid. It contains 100 mg/mL fluorescein (equivalent to 113.2 mg/mL fluorescein sodium). FLUORESCITE injection 10% is supplied as a sterile, unpreserved, pyrogen free, buffered unit dose aqueous solution for use as a diagnostic aid, that has pH of 8.0-9.8 and an osmolality of 572-858 mOsm/kg. FLUORESCITE injection 10% also contains sodium hydroxide and/or hydrochloric acid (to adjust pH) and Water for Injections.
Fluorescein sodium responds to electromagnetic radiation or light between the wavelengths of 465-490 nm and fluoresces, ie. emits light at wavelengths of 520-530 nm. Thus, the fluorescein dye is excited by blue light and emits light that appears yellowish-green. Following intravenous injection of fluorescein sodium in an aqueous solution, the unbound fraction of the fluorescein can be excited with a blue light flash from a fundus camera as it circulates through the ocular vasculature, and the yellowish-green fluorescence of the dye captured on film. In the fundus, the fluorescence of the dye demarcates the retinal and/or choroidal vasculature under observation, distinguishing it from adjacent areas/structures. Some factors that affect the quality of a fluorescein angiogram (i.e. the intensity of fluorescence light) are the intravascular fluorescein concentration, the injection technique, and the status of blood circulation.
Absorption
Following IV and oral administration of 188mg fluorescein sodium in a crossover design using 10 healthy subjects, the mean plasma Cmax values were 10.9 ug/mL (IV) and 3.5 ug/mL (oral), and the mean AUC values were 1350 ug.min/mL (IV) and 1480 ug.min/mL (oral). Peak blood fluorescein concentrations are typically observed within an hour after oral administration. Within 7 to 14 seconds of intravenous administration into the antecubital vein, fluorescein appears in the central artery of the eye. The mean peak concentration of fluorescein sodium in the retinal artery is amounted to 0.5 mg/mL.
Distribution
Fluorescein binds to albumin and red blood cells in a reversible fashion and the binding is moderate (~70-80%) during the first hour. Within a few minutes of intravenous administration of fluorescein sodium, a yellowish discoloration of the skin occurs, which begins to fade after 6 to 12 hours of dosing. Various estimates of volume of distribution indicate that fluorescein distributes well into interstitial space (0.5 to 0.8 L/kg).
Metabolism
Fluorescein undergoes rapid metabolism to fluorescein monoglucuronide. After intravenous administration of fluorescein sodium (14 mg/kg) to 7 healthy subjects, approximately 80% of fluorescein in plasma was converted to glucuronide after a period of 1 hour post dose, indicating relatively rapid conjugation. Fluorescein monoglucuronide is about 1/3 to 1/4 as fluorescent as fluorescein, depending on the wavelength of excitation of the blue light.
Excretion
Fluorescein and its metabolites are mainly eliminated via renal excretion. After intravenous administration, the urine remains slightly fluorescent for 24 to 36 hours. A renal clearance of 1.75 mL/min/kg and a hepatic clearance (due to conjugation) of 1.50 mL/min/kg have been estimated. The systemic clearance of fluorescein was essentially complete by 48 to 72 hours after administration of 500 mg fluorescein.
Indicated in diagnostic fluorescein angiography or angioscopy of the fundus and of the iris vasculature.
Contraindicated in those persons who have shown hypersensitivity to any component of this preparation. FLUORESCITE injection 10% should not be injected intrathecally or intraarterially.
Fluorescein sodium can induce serious hypersensitivity and intolerance reactions. These reactions of intolerance are always unpredictable but they are more frequent in patients who have previously experienced an adverse reaction after fluorescein injection (symptoms other than nausea and vomiting) or in patients with history of allergy such as food or drug induced urticaria, asthma, eczema, allergic rhinitis. In the event of serious hypersensitivity and intolerance reactions during a first angiography, the benefit of an additional fluorescein angiography should be balanced with the risk of severe hypersensitivity reactions (with fatal outcome in some cases). The risk of hypersensitivity reactions with fluorescein sodium requires:
Close monitoring of the patient by the ophthalmologist performing the examination, throughout the examination and for at least 30 minutes thereafter;
Maintaining the infusion line for at least 5 minutes, to treat a possible severe adverse reaction without delay;
To have at one's disposal appropriate material for emergency resuscitation which is based at first on the installation of a 2nd intravenous line, allowing the restoration of the plasma volume (aqueous solution polyionic or colloidal substitute of plasma) and the intravenous injection of adrenaline at the recommended dosage.Extravasation should be avoided during injection as the high pH of fluorescein solution can result in severe local tissue damage. The following complications resulting from extravasation of fluorescein have been noted to occur: sloughing of the skin, superficial phlebitis, subcutaneous granuloma, and toxic neuritis along the median curve in the antecubital area. Complications resulting from extravasation can cause severe pain in the arm for up to several hours. When extravasation occurs, the injection should immediately be discontinued and conservative measures to treat damaged tissue and relieve pain should be implemented. Flush intravenous cannulae before and after drugs are injected to avoid physical incompatibility reactions.
Rare cases of death due to anaphylaxis have been reported with sodium fluorescein injection (see Adverse Reactions). A protocol for management of anaphylaxis, and appropriate resuscitation equipment such as adrenaline for intravenous or intramuscular use, intravenous fluids and oxygen must always be available in case of such a reaction.
Patients with a history of cardiovascular disease require careful evaluation before undergoing an elective procedure with sodium fluorescein. Rarely, severe cardiovascular complications such as chest pain, myocardial infarction and death have occurred following administration of sodium fluorescein. Detailed questioning of each patient must be carried out before the angiography to evaluate any prior history of cardiopulmonary disease or allergy or concomitant medications.
This medicinal product contains up to 3.15 mmol (72.45 mg) sodium per dose. This should be taken into consideration by patients on a controlled sodium diet
The skin and urine may be coloured yellow but this is transient. Fluorescein sodium can stain skin, clothing, and soft contact lenses on contact. Intraocular fluorescein can produce transient blurring of vision.
Fluorescein is a relatively inert dye and specific drug interaction studies are not reported. There are few case reports on potential interactions with organic anion transporters and interference with certain laboratory tests. Compounds that inhibit or compete with the active transport of organic anions (eg. Probenecid) may affect the systemic profile of fluorescein. The concomitant use of Fluorescite 100 mg/ml solution for injection with beta-blocking agents (including eye-drops solutions) may rarely provoke severe anaphylactic reactions. Beta- blocking agents could reduce the vascular compensation reactions to anaphylactic shock and also reduce the effectiveness of adrenaline in the presence of cardiovascular collapse. Do not mix or dilute FLUORESCITE injection 10% with other solutions or drugs. Concomitant intravenous injection of other solutions or the mixing of Fluorescite 100 mg/ml solution for injection with other solutions or drugs should be avoided as the possibility of interactions cannot be excluded
Embryofetal toxicity studies in animals showed that doses of sodium fluorescein associated with exposure levels approximately 9-times higher (rats) or the same (rabbits) as the human dose (on relative mg/m2 body surface area basis) caused no fetal harm when administered IV during organogenesis. Avoid angiography on patients who are pregnant, especially those in the first trimester. There have been no adequate and well-controlled human studies on the safety of FLUORESCITE injection 10% during pregnancy. FLUORESCITE injection 10% should be used in pregnancy only if clearly needed.
Fluorescein has been demonstrated to be excreted in human milk for up to 4 days. Following fluorescein angiography, breast-feeding should therefore be discontinued for at least 4 days and the milk should be pumped off and discarded during this period. Because of the potential for serious reactions in breastfed infants from fluorescein, a decision should be made whether to discontinue breastfeeding or to discontinue the drug, taking into account the importance of the drug to the mother.
Safety and effectiveness in children have not been established.
The benefit to risk of the angiography procedure should be considered in elderly patients with pre-existing conditions such as cardiovascular disease, diabetes mellitus, and multiple concomitant drug therapies. No overall differences in safety or effectiveness have been observed between elderly and other adult patients.
Renal Impairment
Limited experience in renally impaired subjects suggests that no dose adjustment is necessary in renal impaired patients.
Hepatic Impairment
Fluorescein undergoes hepatic metabolism to fluorescein glucuronide. Dose adjustment is not necessary in hepatic impaired patients.
No studies investigating the effect of fluorescein on fertility have been conducted in animals.
No long-term studies in animals to evaluate the carcinogenic potential of fluorescein have been conducted. The genotoxicity of fluorescein has not been investigated.
The patient must be made aware that after application and until visual acuity returns to normal, driving a vehicle or operating dangerous machinery is not recommended
The safety and diagnostic utility of FLUORESCITE Injection 10% were clinically investigated in patients with various ocular pathologies requiring fluorescein angiography including macular degeneration, diabetic retinopathy, macular oedema, intraocular tumors and vascular occlusions. A summary of treatment emergent adverse events based on 4 clinical trials with Fluorescite Injection 10% and 25% (N=735) and their estimate of frequencies (very common, common, uncommon, rare, very rare, and not known) in accordance with preferred term and system organ classes (SOC) of any severity are listed below.
Nervous system disorders:
Common:syncope Uncommon:dizziness, paresthesia Respiratory, thoracic and mediastinal disorders: Uncommon:cough, throat tightness Gastrointestinal disorders: Very Common:nausea Common:vomiting Uncommon:abdominal pain
Skin and subcutaneous tissue disorders:
Uncommon:urticaria
General disorders and administration site conditions:
Common:extravasation Uncommon:dysphasia, feeling hot, pain
Postmarketing Experience
The most frequently reported treatment related undesirable effects were nausea, vomiting, syncope and pruritus. Less frequent but more severe adverse reactions have been reported shortly after fluorescein injection such as respiratory disorders (bronchospasm, laryngeal oedema), anaphylactic shock, hypotension, loss of consciousness, convulsion, respiratory and cardiac arrest. Additionally a yellowish discoloration of the skin could appear but usually disappears within 6 to 12 hours. Urine, which may also exhibit a bright yellow colouration, returns to its normal colour after 24 to 36 hours A summary of treatment emergent adverse events based on literature and postmarketing experience and their estimate of frequencies (very common, common, uncommon, rare, very rare, and not known) in accordance with preferred term and system organ classes (SOC) of any severity are listed below.
Immune system disorders:
Uncommon:hypersensitivity Rare:anaphylactic reaction Very Rare:anaphylactic shock, anaphylactoid reaction, anaphylactoid shock, hypersensitivity
Nervous system disorders:
Common:dysgeusia, syncope Uncommon:headache, paraesthesia, dizziness Very Rare:convulsion Not Known:vertebrobasilar insufficiency, loss of consciousness, tremor, hypoaesthesia,
Cardiac disorders:
Rare:cardiac arrest Very Rare:angina pectoris, bradycardia, tachycardia
Vascular disorders:
Uncommon:thrombophlebitis Rare:hypotension, shock Very Rare:hot flush, hypertension, intermittent claudication, pallor, peripheral vascular disorder, vasodilation, vasospasm
Respiratory, thoracic and mediastinal disorders:
Uncommon:cough, throat tightness Rare:bronchospasm Very Rare:asthma, cough, dyspnoea, hypoventilation, laryngeal oedema, nasal oedema, pulmonary oedema, respiratory arrest, sneezing
Gastrointestinal disorders:
Very Common:nausea Common:abdominal discomfort, vomiting Uncommon:abdominal pain Not Known:retching
Skin and subcutaneous tissue disorders:
Common:pruritus, urticaria Not Known:rash, cold sweat, eczema, erythema, hyperhidrosis
General disorders and administration site conditions:
Common:extravasation Uncommon:pain, feeling hot Very Rare:death Not Known:oedema, malaise, asthenia
The usual adult dose is the contents of one FLUORESCITE injection 10% vial (5 mL of 10% solution) via intravenous administration. For children, the dose is calculated on the basis of 8 mg/kg of body weight. Parenteral drug products should be inspected visually for particulate matter and discolouration prior to administration. Do not mix or dilute with other solutions or drugs. Flush intravenous cannulae before and after drugs are injected to avoid physical incompatibility reactions. Product is for single use in one patient only. Discard any residue. Contains no antimicrobial agent. Inject the contents of the vial rapidly into the antecubital vein after taking precautions to avoid extravasation. A syringe filled with FLUORESCITE injection 10% is attached to transparent tubing and a 23 gauge butterfly needle for injection. Insert the needle and draw the patient's blood to the hub of the syringe so that a small air bubble separates the patient's blood in the tubing from the FLUORESCITE injection 10%. With the room lights on, slowly inject the blood back into the vein while watching the skin over the needle tip. If the needle has extravasated, the patient's blood will be seen to bulge the skin and the injection should be stopped immediately before any FLUORESCITE injection 10% is administered. When assured that extravasation has not occurred, the room light may be switched off and the FLUORESCITE injection 10% administration completed. Luminescence appears in the retina and choroidal vessels in 7 to 14 seconds and can be observed by standard viewing equipment. An emergency tray and oxygen should be present when administering this product (see PRECAUTIONS).
Each vial of FLUORESCITE injection 10%, is considered to be a complete adult dose of fluorescein. An emergency tray (see PRECAUTIONS) should always be available when administering FLUORESCITE injection 10%. No case of overdose has been reported. In the event that an unexpected reaction occurs appropriate supportive therapy should be instituted. In Australia, contact Poisons Information Centre on 13 1126; in New Zealand call 0800 POISON or 0800 764 766 for advice on management.
Prescription Only Medicine
FLUORESCITE injection 10% is supplied as a single use 5 mL glass vial with a gray butyl (latex free) stopper and aluminium flip-off cap. It contains sterile, isotonic, buffered, red- orange solution of fluorescein sodium. Store below 25 C. Do not freeze. Protect from light.
NAME AND ADDRESS OF SPONSOR
FLUORESCITE injection 10% is supplied in Australia by: Alcon Laboratories (Australia) Pty Ltd Unit 10, 25 Frenchs Forest Road East FRENCHS FOREST NSW 2086 In New Zealand this product is distributed by: Alcon Laboratories (Australia) Pty Ltd 4 Fisher Crescent Mt Wellington, Auckland 1060 Approved by TGA on 3 July 2006 Date of last amendment: 02 September 2013
(r) Registered Trademark