Thyroid, desiccated
ARMOUR THYROID
What it isPorcine thyroid extract containing both T4 and T3; hypothyroidism.
Why this oneUnlike levothyroxine, it delivers fixed T3 with T4; some patients prefer that, but the ratio cannot be individualized.
What limits it⚑ Its T3-heavy ratio can produce supraphysiologic peaks, and potency varies by product. Major guidelines prefer levothyroxine.
FDA-approved for
- hypothyroidism (pre-1938 marketed drug; not FDA-approved by NDA)
FDA label
Read the full label on DailyMed ↗
BOXED WARNING Not for treatment of obesity or weight loss; large doses may cause serious or life-threatening toxicity, especially with sympathomimetic amines.
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Hypothyroidism | Adults | 30 mg QD (15 mg QD if long-standing myxedema/CV impairment) | 60-120 mg/day | |
| Congenital hypothyroidism | 0-6 months | 15-30 mg/day | ||
| Congenital hypothyroidism | 6-12 months | 30-45 mg/day | ||
| Congenital hypothyroidism | 1-5 years | 45-60 mg/day | ||
| Congenital hypothyroidism | 6-12 years | 60-90 mg/day | ||
| Congenital hypothyroidism | Over 12 years | Over 90 mg/day |
Titration Increase by 15 mg every 2 to 3 weeks
Renal Undefined
Hepatic Undefined
Failure to respond to 180 mg/day suggests noncompliance or malabsorption
Instructions
- Given orally
- Individualize by indication, patient response, and lab findings
- Appearance of angina is an indication for dose reduction
- Advise stopping biotin supplements at least 2 days before TSH/T4 testing
- Full replacement doses may be started immediately in infants with congenital hypothyroidism
Contraindications
- Uncorrected adrenal cortical insufficiency
- Untreated thyrotoxicosis
Cautions
- Overtreatment causes hyperthyroidism/toxicity
- Caution with cardiovascular disease; may precipitate angina
- Additive effects with sympathomimetic amines
Adverse reactions
- Adverse reactions are generally those of hyperthyroidism from overdosage (e.g., palpitations, tachycardia, tremor, weight loss, heat intolerance)
Pregnancy Undefined
Lactation Undefined
⚠ BOXED WARNING
- Not for treatment of obesity or weight loss
Classes and tags
Clinical profile
Mechanism of action: Thyroid, desiccated ballicule
Open Thyroid, desiccated in the interactive console ↗
Memory aids: mascots and interaction avatars
