Saizen
somatropin, recombinant
Pharmacologic class: Posterior pituitary hormone
Therapeutic class: Growth hormone (GH)
Pregnancy risk category B (Genotropin, Saizen, Serostim), C
Action
Stimulates linear and skeletal growth, increases number and size of muscle cells, and influences internal organ size
Availability
Genotropin injection: 1.5 mg (about 4 international units/vial), 5.8 mg (about 15 international units/vial), 13.8 mg (about 41.4 international units/vial)
Humatrope injection: 2 mg (about 6 international units/vial), 5 mg (about 15 international units/vial), 6 mg (about 18 international units/vial), 12 mg (about 36 international units/vial), 24 mg (about 72 international units/vial)
Norditropin injection: 4 mg (12 international units/vial), 8 mg (24 international units/vial)
Norditropin injection cartridge: 5 mg/1.5 ml, 10 mg/1.5 ml, 15 mg/1.5 ml
Nutropin AQ injection: 10 mg
Nutropin AQ Pen injection cartridge: 10 mg
Nutropin Depot: 13.5-mg, 18-mg, and 22.5-mg single-use vials; 13.5-mg, 18-mg, and 22.5-mg kits
Nutropin injection: 5 mg (about 15 international units/vial), 10 mg (about 30 international units/vial)
Saizem injection: 5 g (about 15 international units/vial)
Serostim injection: 5 mg (about 15 international units/vial), 6 mg (about 18 international units/vial)
Tev-Tropin injection: 5 mg
Zorbtive injection: 8.8 mg in 10-ml vial
Indications and dosages
➣ Growth failure in children with inadequate endogenous GH
Children: 0.16 to 0.24 mg/kg (Genotropin) subcutaneously q week in six or seven divided doses. Or 0.18 mg/kg/week (Humatrope) subcutaneously or I.M., divided equally and given on three alternate days six times weekly (or daily, if epiphyseal closure hasn't occurred). Or 0.024 to 0.034 mg/kg (Norditropin) subcutaneously six or seven times each week using NordiPen injection pen. Or 0.3 mg/kg/week (Nutropin AQ, Nutropin AQ Pen, Tev-Tropin) subcutaneously in equally divided daily doses. Or 0.06 mg/kg (Saizen) subcutaneously or I.M. three times weekly.
➣ Endogenous GH replacement in adults with GH deficiency
Adults: 0.04 mg/kg/week (Genotropin) subcutaneously in six or seven divided doses. Or 0.006 mg/kg/day (Humatrope) subcutaneously. Or initially, no more than 0.006 mg/kg/day (Nutropin AQ, Nutropin AQ Pen, Tev-Tropin) subcutaneously; may increase to a maximum of 0.025 mg/kg daily in patients younger than age 35 or 0.0125 mg/kg/day in patients ages 35 and older. Or 0.005 mg/kg/day (Saizen) subcutaneously; may increase to a maximum of 0.01 mg/kg/day after 4 weeks, depending on patient tolerance.
➣ Short stature related to Turner's syndrome
Children: 0.375 mg/kg/week (Humatrope) subcutaneously, divided into equal doses given on 3 alternate days or daily. Or up to 0.375 mg/kg/week (Nutropin AQ, Nutropin AQ Pen) subcutaneously, divided into equal doses given three or seven times weekly.
➣ Idiopathic short stature (non-GH-deficient) in children whose epiphyses haven't closed
Children: Up to 0.37 mg/kg (Humatrope) subcutaneously q week. Divide dosage and give in equal doses six or seven times weekly.
➣ Growth failure in children with Prader-Willi syndrome
Children: 0.24 mg/kg/week (Genotropin) subcutaneously in six or seven divided doses
➣ Infants born small for gestational age
Children: 0.48 mg/kg/week (Genotropin) subcutaneously in six or seven divided doses
➣AIDS wasting or cachexia
Adults and children weighing more than 55 kg (121 lb): 6 mg (Serostim) subcutaneously at bedtime
Adults and children weighing 45 to 55 kg (99 to 121 lb): 5 mg (Serostim) subcutaneously at bedtime
Adults and children weighing 35 to 45 kg (77 to 99 lb): 4 mg (Serostim) subcutaneously at bedtime
Adults and children weighing less than 35 kg (77 lb): 0.1 mg/kg/day (Serostim) subcutaneously at bedtime
➣ Growth failure due to chronic renal insufficiency (up to time of kidney transplantation)
Children: Up to 0.35 mg/kg/weekly (Nutropin AQ, Nutropin AQ Pen) subcutaneously, divided into daily doses
➣ Short bowel syndrome in patients receiving specialized nutritional support
Adults: 0.1 mg/kg/day subcutaneously (Zorbtive), to a maximum of 8 mg/day for no more than 4 weeks
Contraindications
• Hypersensitivity to drug, benzyl alcohol, glycerin, or metacresol (with some diluents)
• Active neoplasia
• Acute, critical illness after open-heart surgery, acute respiratory failure, or multiple trauma
• Children with closed epiphyses
• Neonates (Zorbtive)
Precautions
Use cautiously in:
• hypothyroidism
• diabetes mellitus.
Administration
• Reconstitute by injecting supplied diluent through rubber top of vial and aiming liquid stream at side of vial. Swirl vial gently to mix; don't shake.
• Inspect reconstituted solution. Don't use if it has visible particles or is cloudy.
• Keep diluted drug refrigerated; use within 14 days.
• When using prefilled cartridges, follow manufacturer's instructions carefully.
• Know that patients receiving Zorbtive for short bowel syndrome may receive specialized nutritional support as needed.
Adverse reactions
CNS: headache, weakness
CV: mild and transient edema
GU: hypercalciuria
Hematologic: leukemia
Metabolic: fluid retention, mild hyperglycemia, hypothyroidism, ketosis
Musculoskeletal: localized muscle pain, tissue swelling, joint pain
Skin: rash, urticaria
Other: pain, inflammation at injection site
Interactions
Drug-drug. Androgens, thyroid hormone: epiphyseal closure
Corticotrophin, corticosteroids: inhibited growth response (with long-term use)
Drug-diagnostic tests. Alkaline phosphatase, glucose, inorganic phosphorus, parathyroid hormone: increased levels
Patient monitoring
• Monitor patient's height, X-rays, blood chemistry results, blood glucose level, and thyroid function studies.
See Watch for signs and symptoms of leukemia.
Patient teaching
• Advise patient and parents that regular check-ups and blood tests are needed to detect adverse reactions.
• Teach parents how to reconstitute and administer drug. Stress importance of following manufacturer's instructions carefully when using prefilled cartridges.
• Teach parents about proper handling and disposal of syringes, needles, and cartridges.
• As appropriate, review all significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.
somatropin (recombinant)
(soe-ma-troe-pin) somatropinsaizen,Saizen
(trade name)Classification
Therapeutic: hormonesPharmacologic: growth hormones
Indications
Action
- Increased protein synthesis,
- Increased carbohydrate metabolism,
- Lipid mobilization,
- Retention of sodium, phosphorus, and potassium.
Therapeutic effects
Pharmacokinetics
Time/action profile (growth)
| ROUTE | ONSET | PEAK | DURATION |
|---|---|---|---|
| IM, subcut | within 3 mo | unknown | 12–48 hr |
Contraindications/Precautions
Adverse Reactions/Side Effects
Cardiovascular
- edema of the hands and feet
Dermatologic
- exacerbation of pre-existing psoriasis
Endocrinologic
- hyperglycemia
- hypothyroidism
- insulin resistance
Local
- pain at injection site
- local lipoatrophy or lipodystrophy with subcutaneous use
Musculoskeletal
- arthralgia,
- musculoskeletal pain,
- swelling,
- stiffness
Interactions
Drug-Drug interaction
Excessive corticosteroid use (equivalent to 10–15 mg/m2/day) may ↓ response to growth hormone.Route/Dosage
Availability
Nursing implications
Nursing assessment
- Growth Failure: Monitor bone age annually and growth rate determinations, height, and weight every 3–6 mo during therapy.
- Lab Test Considerations: Monitor thyroid function prior to and during therapy. May decrease T4, radioactive iodine uptake, and thyroxine-binding capacity. Hypothyroidism necessitates concurrent thyroid replacement for growth hormone to be effective. Serum inorganic phosphorus, alkaline phosphatase, and parathyroid hormone may ↑ with somatropin therapy.
- Monitor blood glucose periodically during therapy. Diabetic patients may require ↑ insulin dose.
- Monitor for development of neutralizing antibodies if growth rate does not exceed 2.5 cm/6 mo.
- Monitor alkaline phosphatase closely in patients with adult growth hormone deficiency.
Potential Nursing Diagnoses
Disturbed body image (Indications)Implementation
- Rotate injection sites with each injection.
- Saizen: Reconstitute each 5-mg vial with 1–3 mL of bacteriostatic water for injection; use 2–3 mL for 8.8 mg vial. Aim the liquid against glass vial wall. Do not shake; swirl gently to dissolve. Solution is clear; do not use solutions that are cloudy or contain a precipitate. Reconstituted vials are stable for 14 days if refrigerated. To use cool.click needle-free injector, wind the device to energize the spring, and draw medication into the Crystal Check nozzle. Using firm pressure at the injection site, hold the injector at a 90° angle and press the blue actuator button.
- Subcutaneous: Injection volume should not exceed 1 mL.
Patient/Family Teaching
- Instruct patient and parents on correct procedure for reconstituting medication, site selection, technique for subcut injection, and disposal of needles and syringes. Review dosage schedule. Parents should report persistent pain or edema at injection site.
- Explain rationale for prohibition of use for increasing athletic performance. Administration to persons without growth hormone deficiency or after epiphyseal closure may result in acromegaly (coarsening of facial features; enlarged hands, feet, and internal organs; increased blood glucose; hypertension).
- Emphasize need for regular follow-up with endocrinologist to ensure appropriate growth rate, to evaluate lab work, and to determine bone age by x-ray exam.
- Assure parents and child that these dose forms are synthetic and therefore not capable of transmitting Creutzfeldt-Jakob disease, as was the original somatropin, which was extracted from human cadavers.
Evaluation/Desired Outcomes
- Child’s attainment of adult height in growth failure secondary to pituitary growth hormone deficiency. Therapy is limited to period before closure of epiphyseal plates (approximately up to 14–15 yr in girls, 15–16 yr in boys).
- Replacement of growth hormone in deficient adults.