Free Article Directory Colorado: Liothyronine Sodium Injection BP 20 mcg

1. Name Of The Medicinal Product

Liothyronine Sodium Injection BP 20 mcg

2. Qualitative And Quantitative Composition

Each vial contains 20 micrograms liothyronine sodium

For excipients, see 6.1

3. Pharmaceutical Form

Intravenous injection

Packed as a freeze dried white plug, in a glass vial for reconstitution with 1 or 2ml water for injection.

4. Clinical Particulars

4.1 Therapeutic Indications

Liothyronine Sodium Injection is indicated for the treatment of myxoedema coma, usually in conjunction with other measures including the intravenous injection of a corticosteroid. For the treatment of less severe forms of myxoedema and for maintenance therapy, orally administered liothyronine should be used.

4.2 Posology And Method Of Administration

5 to 20 micrograms given by slow intravenous injection, and repeated at intervals of 12 hours or less if required. The minimal interval between dosing is 4 hours. An initial dose of 50 micrograms intravenously is used by some physicians, followed by further intravenous injections of 25 micrograms every 8 hours until improvement occurs. The dosage may then be reduced to 25 micrograms intravenously twice daily.

Method of Administration:

Usually given by intravenous injection, as the alkalinity of the solution may cause irritation of the tissues if given by deep intramuscular injection. The solution is prepared by adding 1 or 2ml water of injection to the ampoule, and shaking gently until the solution has dissolved.

4.3 Contraindications

Hypersensitivity to any components of the preparation. Liothyronine sodium is contraindicated in patients with cardiovascular disorders or angina of effort.

4.4 Special Warnings And Precautions For Use

Liothyronine must be given with extreme caution in myxoedema coma because too large a dose can precipitate heart failure, especially in elderly patients and those with ischaemic heart disease. ECG monitoring can give a useful indication of impending ishcaemia, however, changes in ST segment can be confused with similar changes occurring in hypothyroidism. In severe and prolonged hypothyroidism, there may be decreased adrenocortical activity. When thyroid replacement therapy is started, metabolism is raised at a greater rate that adrenocortical activity, and this can result in adrenocortical insufficiency. This insufficiency may require supplemental adrenocoritcal steroids. Thyroid replacement therapy may cause an increase in the dosage requirement of insulin or other anti-diabetic treatment. Care is needed in patients with diabetes mellitus and diabetes insipidus.

4.5 Interaction With Other Medicinal Products And Other Forms Of Interaction

Liothyronine sodium therapy may potentiate the action of anticoagulants.

Anticonvulsant, such as carbamazepine and phenytoin-enhance the metabolism of thyroid hormones and may displace thyroid hormones from plasma proteins.

Initiation or discontinuation of anticonvulsant therapy may alter liothyronine dose requirements. Phenytoin levels may be increased by liothyronine.

Liothyronine raises blood sugar levels and this may upset the stability of patients receiving antidiabetic agents. If co-administered with cardiac glycosides, adjustment of dosage of cardiac glycoside may be necessary.

Liothyronine increases receptor sensitivity to catecholamines thus, accelerating the response to tricyclic antidepressants. A number of drugs may affect thyroid function tests and this should be borne in mind when monitoring patients on liothyronine therapy.

Co-administration with oral contraceptives may result in an increased dosage requirement of liothyronine sodium.

4.6 Pregnancy And Lactation

Pregnancy:

The safety of liothyronine during pregnancy is not known. Any possible risk of congenital abnormalities must be weighed against the risk to the foetus of untreated hypothyroidism in the mother.

Lactation:

Liothyronine is excreted into breast milk in low concentration. This may interfere with neonatal screening programmes.

4.7 Effects On Ability To Drive And Use Machines

Not relevant.

4.8 Undesirable Effects

The following are indicative of overdosage, and disappear after reduction of dosage or stopping treatment for a day or more:

Anginal pain, cardiac arrhythmias, palpitations, cramps, tachycardia, diarrhoea, restlessness, excitability, headache, flushing, sweating, excessive loss of weight and muscular weakness.

4.9 Overdose

Overdose may present as an exaggeration of the side-effects, as well as agitation, confusion, irritability, hyperactivity, headache, sweating, mydriasis, tachycardia, arrhythmias, tachypnoea, pyrexia, increased bowel movements and convulsions.

Treatment is symptomatic. In adults, tachycardia has been controlled by 40mg propanolol every six hours.

5. Pharmacological Properties

5.1 Pharmacodynamic Properties

Liothyronine (L-triiodothyronine) is a naturally occurring thyroid hormone. Its biological action is qualitatively similar to that thyroxine, but the effect is more rapid in onset (in a few hours) and the effect disappears within 24 to 48 hours after stopping treatment.

5.2 Pharmacokinetic Properties

Liothyronine is less readily bound to plasma proteins than thyroxine, and about 0.5% exists in the unbound form. The half-life in the blood is about one to two days in euthyroidism. Thyroid hormones do not readily cross the placenta. Minimal amounts are reported excreted in breast milk.

5.3 Preclinical Safety Data

No additional data.

6. Pharmaceutical Particulars

6.1 List Of Excipients

Dextran 110, freeze dried

Sodium Hydroxide

Water for Injection

6.2 Incompatibilities

Not applicable.

6.3 Shelf Life

12 months

6.4 Special Precautions For Storage

Do not store above 25°C.

Keep the vial in the outer carton in order to protect from light.

6.5 Nature And Contents Of Container

3ml hydrolytic clear glass vial with bromobutyl stopper containing 20 micrograms of Liothyronine Sodium in a freeeze-dried, sterile white plug, packed into a carton containing 5 vials.

6.6 Special Precautions For Disposal And Other Handling

No special requirements.

7. Marketing Authorisation Holder

Goldshield Pharmaceuticals Limited

NLA Tower

12-16 Addiscombe Road

Croydon

Surrey CR0 0XT

United Kingdom

8. Marketing Authorisation Number(S)

PL 12762/0176

9. Date Of First Authorisation/Renewal Of The Authorisation

08/10/2007

10. Date Of Revision Of The Text