TRIAMCINOLONE DIACETATE
Clinical safety rating: avoid
CYP3A4 inducers (eg phenytoin) may decrease efficacy and inhibitors may increase effects Can cause hyperglycemia and adrenal suppression with prolonged use.
Corticosteroid with anti-inflammatory and immunosuppressive properties; binds to glucocorticoid receptor, modulating gene expression and suppressing cytokine production, inflammation, and immune cell activity.
| Metabolism | Primarily hepatic via CYP3A4; undergoes reduction and conjugation; inactive metabolites excreted in urine and bile. |
| Excretion | Triamcinolone diacetate is metabolized primarily in the liver and excreted via the kidneys as inactive metabolites. Approximately 30-40% of an oral dose is excreted in urine as metabolites, with less than 5% as unchanged drug. Biliary/fecal excretion accounts for about 60-70% of the administered dose. |
| Half-life | The terminal elimination half-life is approximately 2-5 hours in adults. This relatively short half-life supports multiple daily dosing for chronic conditions, though the biological half-life (duration of adrenal suppression) is longer at 18-36 hours due to intracellular receptor binding. |
| Protein binding | Triamcinolone is approximately 68% bound to plasma proteins, primarily corticosteroid-binding globulin (CBG) and albumin. |
| Volume of Distribution | Volume of distribution is approximately 1.4 L/kg, indicating extensive tissue distribution and penetration into intracellular spaces. This reflects its lipophilic nature and ability to cross cell membranes. |
| Bioavailability | Oral: 20-25% due to first-pass metabolism in the liver. IM: 100% absolute bioavailability; intra-articular: locally high concentrations with negligible systemic absorption. |
| Onset of Action | Oral: 1-2 hours; intramuscular (IM) depot: 24-48 hours; intra-articular: 24-72 hours. Onset is delayed for sustained-release formulations. |
| Duration of Action | Oral: 12-36 hours; IM depot: 2-3 weeks; intra-articular: 4-6 weeks. Duration is prolonged due to slow release from esterified formulations and receptor-mediated effects. |
40 to 80 mg intramuscularly every 4 weeks; intra-articular: 5 to 40 mg per joint every 3-4 weeks; intralesional: up to 1 mg per injection site, not to exceed 0.1 mg per cm² of lesion.
| Dosage form | INJECTABLE |
| Renal impairment | No specific dosage adjustment required for renal impairment; caution in severe impairment due to risk of fluid retention. |
| Liver impairment | No specific dosage adjustment guidelines; use with caution in severe hepatic impairment due to potential for increased systemic effects. |
| Pediatric use | Not recommended for children under 12 years; for adolescents, dosing based on adult recommendations with caution. |
| Geriatric use | Start at lower end of dosing range; monitor for increased adverse effects such as hyperglycemia, osteoporosis, and fluid retention. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
CYP3A4 inducers (eg phenytoin) may decrease efficacy and inhibitors may increase effects Can cause hyperglycemia and adrenal suppression with prolonged use.
| FDA category | Positive |
| Breastfeeding | Enters breast milk in low concentrations (M/P ratio ~0.3-0.5). Systemic absorption via nursing is minimal; no reported adverse effects in infants. Use caution with high maternal doses or prolonged therapy; monitor infant for signs of adrenal suppression. |
| Teratogenic Risk |
■ FDA Black Box Warning
None.
| Common Effects | Hyperglycemia |
| Serious Effects |
Systemic fungal infections; hypersensitivity to triamcinolone or any component; administration of live or live-attenuated vaccines in immunosuppressive doses; idiopathic thrombocytopenic purpura (IM use); intrathecal administration (meningeal irritation); relative: active infections, tuberculosis, uncontrolled diabetes, hypertension, glaucoma, osteoporosis, pregnancy (should be used only if potential benefit justifies risk).
| Precautions | Immunosuppression increased infection risk; adrenal suppression with prolonged use; Cushing's syndrome; osteoporosis; avascular necrosis; exacerbation of fungal, bacterial, viral infections; avoid live vaccines; monitoring for HPA axis suppression; potential for growth retardation in children; use with caution in diabetes, hypertension, congestive heart failure, peptic ulcer disease, ulcerative colitis, diverticulitis, renal insufficiency, hypothyroidism, cirrhosis, ocular herpes simplex. |
Loading safety data…
| First trimester: Increased risk of cleft palate (odds ratio 3.4) and neural tube defects. Second trimester: Risk of intrauterine growth restriction and premature rupture of membranes with systemic use. Third trimester: Risk of neonatal adrenal suppression, hypoglycemia, and transient growth retardation. Corticosteroids are classified as FDA Category C; avoid systemic use in first trimester unless life-threatening. |
| Fetal Monitoring | Monitor maternal blood pressure, blood glucose (risk of hyperglycemia), and signs of infection. Serial fetal growth ultrasounds (every 4-6 weeks) for intrauterine growth restriction. Assess fetal well-being with nonstress testing or biophysical profile if high-dose therapy. Monitor neonatal adrenal function after delivery (serum cortisol, ACTH stimulation test). |
| Fertility Effects | May disrupt ovarian function and menstrual regularity via hypothalamic-pituitary-adrenal suppression. Reversible impaired fertility in both sexes (reduced sperm count and motility). Use for chronic conditions may delay time to conception; avoid if actively trying to conceive unless necessary. |