30mg / 1/2 grain
30mg / 1/2 grain is a prescriber-directed compounded preparation prepared or dispensed for patient-specific use within the Hormone Optimization therapy area. Genesis should dispense this medication only pursuant to a valid prescription and the prescriber's clinical judgment.
This is a compounded thyroid hormone preparation at 30 mg (one-half grain), providing approximately 19 mcg levothyroxine (T4) and 4.5 mcg liothyronine (T3) based on the established grain ratio. The 30 mg (½ grain) strength serves as a standard low-dose initiation point for most patients beginning thyroid hormone replacement therapy, or as a dose-step during titration. Genesis Compounding prepares this as a patient-specific, prescriber-directed 503A preparation; it is not FDA-approved as a compounded preparation.
| Active Ingredient | Pharmacologic Role |
|---|---|
| Levothyroxine (T4) ~19 mcg per 30 mg (½ grain) | Prohormone T4 undergoes peripheral deiodination to active T3 and directly binds nuclear thyroid hormone receptors (as T3), regulating metabolism, thermogenesis, cardiac function, and growth. |
| Liothyronine (T3) ~4.5 mcg per 30 mg (½ grain) | Active thyroid hormone with direct, high-affinity binding to TRα and TRβ nuclear receptors; approximately four times as potent as T4 per microgram, providing immediate thyromimetic activity. |
Oral administration (capsule or tablet).
- Administer on an empty stomach, 30–60 minutes before the first meal of the day.
- Take with adequate water; do not crush or chew.
- Separate from calcium, iron, antacids, and other absorption-inhibiting agents by at least 4 hours.
30 mg (½ grain) is the standard starting dose for most adults beginning thyroid hormone replacement, per established prescribing references:
- The usual starting dose is 30 mg/day, with increases of 15 mg every 2–3 weeks based on clinical response and labs.
- For high-risk patients (elderly, cardiovascular disease), the starting dose may be 15 mg (¼ grain), titrating up to 30 mg as tolerated.
- Most patients require 60–120 mg/day as a maintenance dose.
- Final dosing is prescriber-determined based on individual TSH, free T4, free T3, and clinical response.
- Levothyroxine (T4): Serves as a reservoir hormone; peripheral deiodination by type 1 and type 2 iodothyronine deiodinases converts T4 to T3 in liver, kidney, and other tissues. T3 then activates TRα/TRβ nuclear receptors to regulate transcription of metabolic genes.
- Liothyronine (T3): Directly occupies nuclear thyroid hormone receptors with high affinity, rapidly exerting thyromimetic effects on basal metabolic rate, cardiac chronotropy, and thermogenesis.
The 30 mg (½ grain) strength is the most common starting point for thyroid hormone replacement, used in:
- Primary hypothyroidism (Hashimoto's thyroiditis, post-ablation, idiopathic).
- Secondary and tertiary hypothyroidism (pituitary or hypothalamic origin).
- Patients requiring individualized T4/T3 combination therapy who have not achieved full symptomatic resolution on levothyroxine monotherapy.
Monitoring:
- Check TSH, free T4, and free T3 at 4–6 weeks after initiation and after each dose change.
- Target TSH range is typically 0.5–2.5 mIU/L for most patients, but should be individualized.
- Monitor for symptoms of thyroid excess (palpitations, tremor, insomnia) during initiation.
Contraindications:
- Untreated adrenal insufficiency.
- Active thyrotoxicosis.
- Hypersensitivity to components.
Warnings & Precautions:
- Cardiovascular monitoring during initiation is warranted, particularly in elderly patients.
- Biotin supplementation causes assay interference; hold ≥48 hours before labs.
- Adjust concomitant diabetes medications as thyroid status normalizes.
Drug Interactions:
- Warfarin: enhanced anticoagulant effect during thyroid replacement initiation or dose changes.
- Calcium salts, iron, antacids, cholestyramine: significantly impair oral thyroid hormone absorption.
- Sympathomimetics (epinephrine): additive cardiovascular risk with thyroid hormones.
Common Side Effects: At supratherapeutic levels — tachycardia, palpitations, sweating, heat intolerance, nervousness, weight loss, diarrhea.
Store at controlled room temperature (15–25°C), protected from light, heat, and moisture. Keep in original container with lid tightly closed. Keep out of reach of children. Observe the beyond-use date assigned by Genesis Compounding. Do not use after the BUD.
Is 30 mg (½ grain) a full therapeutic dose?
No. For most adults, 30 mg is a starting dose. Full therapeutic maintenance typically falls between 60–120 mg (1–2 grains). Your prescriber will gradually increase your dose based on lab results and how you feel.
When should I take this medication?
Take it on an empty stomach, 30–60 minutes before breakfast. Separate from calcium, iron, and antacid supplements by at least 4 hours.
What lab tests are needed?
TSH, free T4, and free T3 should be measured 4–6 weeks after starting or adjusting the dose. Biotin (vitamin B7) can interfere with thyroid tests — hold it for at least 48 hours before blood draws.
Is this preparation FDA-approved?
No. This is a patient-specific, 503A compounded preparation from Genesis Compounding. It is not FDA-approved as a finished drug product.
How long before I feel better?
Symptomatic improvement often begins within 2–4 weeks of reaching a therapeutic dose. Full biochemical normalization typically occurs within 4–6 weeks. It may take several dose adjustments to achieve the optimal individual dose.
Clinical References
Authoritative sources reviewed in preparing this clinical summary. Provided for prescriber reference; not a substitute for the prescriber’s clinical judgment.