TRIIODOTHYRONINE

brands

Class

• Synthetic hormone; antidepressant adjunct

TRIIODOTHYRONINE commonly prescribed for

(Bold for FDA approved)

How TRIIODOTHYRONINE works

• Hypothetically boosts monoamine actions in the CNS

• May work synergistically with traditional antidepressants

How long until TRIIODOTHYRONINE works

• Can work within days, but therapeutic effects may be delayed for up to 8 weeks

Notable Side Effects

• Hyperthyroidism (headache, irritability, nervousness, sweating, arrhythmia, increased bowel motility, menstrual irregularities)

• Possible acceleration of bone demineralization, especially in postmenopausal women (controversial)

Life Threatening Side Effects

• Angina pectoris, congestive heart failure

• Shock

weight gain

unusual

sedation

unusual

What to do about TRIIODOTHYRONINE side effects

• Wait

• Wait

• Wait

• In a few weeks, switch to another agent

usual dosage range

• 25–50 μg/day

Dosage Forms

• Tablet 5 μg, 25 μg, 50 μg

long term use

• Has not been evaluated in controlled studies, but long-term treatment of major depressive disorder is generally necessary

habit forming

• No

Renal Impairment

• No dose adjustment necessary

Hepatic Impairment

• No dose adjustment necessary

Cardiac Impairment

• Use with caution

• Requires dose reduction: initial 5 μg; increase by no more than 5 μg at 2-week intervals; reduce dose if cardiovascular disease is aggravated

Elderly

• Some patients may tolerate lower doses better

Children and Adolescents

• Thyroid hormone is used safely in infants, children, and adolescents for hypothyroidism

• Not studied for use as adjunct in depression

Pregnancy

• Effective June 30, 2015, the FDA requires changes to the content and format of pregnancy and lactation information in prescription drug labels, including the elimination of the pregnancy letter categories; the Pregnancy and Lactation Labeling Rule (PLLR or final rule) applies only to prescription drugs and will be phased in gradually for drugs approved on or after June 30, 2001

• Adequate, well-controlled studies in pregnant women have failed to demonstrate risk to the fetus

• Thyroid hormones do not readily cross the placental barrier, and the clinical experience to date does not indicate any adverse effect on fetuses when thyroid hormones are administered to pregnant women

Breast Feeding

• Some drug is found in mother’s breast milk

• No known adverse effects but use should be cautious

• Must weigh benefits of breast feeding with risks and benefits of treatment versus nontreatment to both the infant and the mother

• For many patients, this may mean continuing treatment during breast feeding