Oxandrolone (Anavar) vs Thyroid (Levothyroxine / Liothyronine T3/T4)

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

Oxandrolone (Anavar)Thyroid (Levothyroxine / Liothyronine T3/T4)
CategoryHormonesHormones
Standard DoseResearch indicates 5-20 mg/day orally for therapeutic/recovery applications. Clinical burn protocols use 0.1 mg/kg twice daily.Research indicates Levothyroxine (T4): 25-200 mcg daily based on TSH and free T4 levels. Liothyronine (T3): 5-25 mcg daily, often split into 2-3 doses. Combination T4/T3 ratio typically 4:1 to 3:1 when using both.
TimingSplit into 2 doses (morning and evening) due to 9-hour half-life. Take with food to reduce GI discomfort.Levothyroxine: Take on empty stomach, 30-60 minutes before breakfast or at bedtime (3+ hours after last meal). Separate from calcium, iron, and antacids by 4 hours. Liothyronine: Split into 2-3 daily doses due to short half-life (2.5 hours for T3 vs. 6-7 days for T4).
Cycle DurationTypical therapeutic cycles: 6-12 weeks. Clinical burn protocols have extended to 1 year+ with liver monitoring. Limit cycle length to minimize hepatic stress.Ongoing for diagnosed hypothyroidism. Optimization protocols may be shorter-term (3-6 months) with reassessment.
Evidence Levelstrong_humanstrong_human

Mechanism

Oxandrolone is a synthetic 17-alpha-alkylated dihydrotestosterone (DHT) derivative with a modified A-ring (replacement of C2 with an oxygen atom) that confers high anabolic-to-androgenic ratio (~10:1). It enhances protein synthesis by activating the androgen receptor while strongly binding sex hormone-binding globulin (SHBG), increasing free testosterone fraction. Oxandrolone directly stimulates phosphocreatine synthesis in skeletal muscle and has demonstrated anti-catabolic effects through cortisol receptor antagonism. In burn patients, it reverses catabolism by restoring the IGF-1/IGFBP-3 axis.

Standard Dosing

Research indicates 5-20 mg/day orally for therapeutic/recovery applications. Clinical burn protocols use 0.1 mg/kg twice daily.

Timing

Split into 2 doses (morning and evening) due to 9-hour half-life. Take with food to reduce GI discomfort.

Cycle Duration

Typical therapeutic cycles: 6-12 weeks. Clinical burn protocols have extended to 1 year+ with liver monitoring. Limit cycle length to minimize hepatic stress.

Side Effects

  • Hepatotoxicity (dose and duration dependent — mild with therapeutic doses)
  • Lipid profile disruption (significant HDL suppression, LDL elevation)
  • Suppression of endogenous testosterone (dose dependent)
  • Virilization in females at higher doses
  • Headache
  • Nausea
  • Potential hair loss in genetically susceptible individuals

Contraindications

  • Prostate cancer
  • Breast cancer in males
  • Hypercalcemia
  • Severe hepatic impairment or active liver disease
  • Nephrotic syndrome
  • Pregnancy (Category X)

Best Stacking Partners

Testosterone (to maintain hormonal base)BPC-157 (recovery synergy)NAC or TUDCA (liver support)Creatine (synergistic phosphocreatine loading)

Mechanism

Levothyroxine (T4) is a prohormone converted to the active triiodothyronine (T3) by type 1 and type 2 deiodinase enzymes (DIO1/DIO2) in peripheral tissues. T3 binds nuclear thyroid hormone receptors (TRa and TRb), forming heterodimers with retinoid X receptors (RXR) that bind thyroid response elements (TREs) in DNA, directly modulating transcription of genes controlling basal metabolic rate, thermogenesis, mitochondrial biogenesis (via PGC-1a), cardiac output, and neuronal development. T3 also exerts rapid non-genomic effects on mitochondrial respiration, ion channels, and cell membrane transport.

Standard Dosing

Research indicates Levothyroxine (T4): 25-200 mcg daily based on TSH and free T4 levels. Liothyronine (T3): 5-25 mcg daily, often split into 2-3 doses. Combination T4/T3 ratio typically 4:1 to 3:1 when using both.

Timing

Levothyroxine: Take on empty stomach, 30-60 minutes before breakfast or at bedtime (3+ hours after last meal). Separate from calcium, iron, and antacids by 4 hours. Liothyronine: Split into 2-3 daily doses due to short half-life (2.5 hours for T3 vs. 6-7 days for T4).

Cycle Duration

Ongoing for diagnosed hypothyroidism. Optimization protocols may be shorter-term (3-6 months) with reassessment.

Side Effects

  • Tachycardia and palpitations (overdose or too-rapid titration)
  • Anxiety and insomnia (particularly with T3)
  • Tremor
  • Weight loss (excessive dosing)
  • Hair loss (temporary during initiation or dose changes)
  • Heat intolerance and sweating
  • Bone density loss at suppressive doses (TSH <0.1)

Contraindications

  • Untreated adrenal insufficiency (correct cortisol before thyroid replacement)
  • Acute myocardial infarction
  • Thyrotoxicosis
  • Known hypersensitivity to levothyroxine or liothyronine

Best Stacking Partners

Selenium (supports DIO2 deiodinase conversion)Zinc (cofactor for thyroid hormone synthesis)Iron (required for thyroid peroxidase function)Iodine (substrate for T3/T4 synthesis — only if deficient)

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