Drug Guide
Triptorelin Pamoate
Classification
Therapeutic: Hormonal Agent, Gonadotropin-Releasing Hormone (GnRH) Agonist
Pharmacological: GnRH Agonist
FDA Approved Indications
- Prostate cancer treatment
- Endometriosis
- Precocious puberty
Mechanism of Action
Triptorelin is a synthetic GnRH agonist that initially stimulates, then downregulates GnRH receptors in the pituitary gland, leading to decreased secretion of LH and FSH, and consequently reducing sex hormone production.
Dosage and Administration
Adult: For prostate cancer: 3.75 mg IM every 4 weeks or 11.25 mg IM every 12 weeks. Adjust based on clinical response.
Pediatric: Dosing depends on condition; consult specific guidelines.
Geriatric: No specific dose adjustment; monitor for side effects.
Renal Impairment: Use caution; no specific adjustment established.
Hepatic Impairment: No specific adjustment necessary.
Pharmacokinetics
Absorption: IM injection provides slow release and absorption.
Distribution: Widely distributed; crosses blood-brain barrier.
Metabolism: Metabolized in the liver.
Excretion: Excreted primarily in the urine.
Half Life: Varies; sustained release formulations have a prolonged half-life (approximately 3-4 weeks).
Contraindications
- Hypersensitivity to triptorelin or GnRH analogs.
Precautions
- Monitor for tumor flare reactions, especially at therapy initiation.
- Use with caution in patients with osteoporosis, cardiovascular disease, or risk factors for thromboembolism.
- Pregnancy Category X; contraindicated in pregnancy.
Adverse Reactions - Common
- Hot flashes (Common)
- Skin reactions at injection site (Common)
- Headache (Common)
Adverse Reactions - Serious
- Tumor flare symptoms (pain, swelling) (Less common)
- Hypersensitivity reactions (Rare)
- Bone mineral density loss with long-term use (Potential concern)
Drug-Drug Interactions
- Caution with medications affecting bone density, anticoagulants, or drugs affecting liver metabolism.
Drug-Food Interactions
- No significant interactions reported.
Drug-Herb Interactions
- Limited data; caution advised with herbal supplements.
Nursing Implications
Assessment: Assess baseline hormone levels, tumor size, and symptoms.
Diagnoses:
- Risk of tumor flare
- Risk for bone demineralization
- Altered hormonal status
Implementation: Administer IM injections as scheduled, monitor for injection site reactions, assess for symptoms of tumor progression or flare.
Evaluation: Monitor symptom relief, hormone levels, and adverse effects.
Patient/Family Teaching
- Explain purpose and expected effects of therapy.
- Instruct on injection site care.
- Inform about potential side effects such as hot flashes and bone density loss.
- Advise to report any severe pain, swelling, or allergic reactions.
Special Considerations
Black Box Warnings:
- Tumor flare reaction may occur upon initiation, leading to pain or worsening symptoms.
Genetic Factors: No specific genetic considerations.
Lab Test Interference: May alter testosterone and estrogen levels, affecting diagnostic tests.
Overdose Management
Signs/Symptoms: Severe allergic reactions, signs of hormonal imbalance.
Treatment: Supportive care, antihistamines, corticosteroids as needed; no specific antidote.
Storage and Handling
Storage: Store at controlled room temperature, protect from light.
Stability: Stable under recommended storage conditions.