Somatrem
Somatrem (Protropin)
Somatrem/Somatropin
( SO-mah-trem)
Pregnancy Category: C Protropin (Rx)
Somatropin
Somatropin (Humatrope, Nutropin)
Somatrem/Somatropin
(so-mah- TROH-pin)
Pregnancy Category: C, Serostim is B Genotropin Humatrope Norditropin Nutropin Nutropin AQ Saizen Serostim (Rx)

Classification: Growth hormone

Action/Kinetics: Both somatrem and somatropin are derived from recombinant DNA technology. Somatrem contains the same sequence of amino acids (191) as human growth hormone derived from the pituitary gland plus one additional amino acid (methionine). Somatropin has the identical sequence of amino acids as does human growth hormone of pituitary origin. These agents stimulate linear growth by increasing somatomedin-C serum levels, which, in turn, increases the incorporation of sulfate into proteoglycans, thereby stimulating skeletal growth. They also increase the number and size of muscle cells, increase synthesis of collagen, increase protein synthesis, and increase internal organ size. Serum insulin levels increase (indicative of insulin resistance), and there is acute mobilization of lipid. Peak plasma levels, somatotropin: 7.5 hr after SC. t 1/2, somatotropin: 3.8 hr after SC and 4.9 hr after IM.

Uses: Treat growth failure associated with chronic renal insufficiency up to the time of renal transplantation. Except for Serostim to stimulate linear growth of children who suffer from lack of adequate levels of endogenous growth hormone. Humatrope and Genotropin have been approved for the treatment of somatropin deficiency syndrome in adults. In adults, Humatrope produces increased lean muscle mass and exercise capacity, decreased body fat, and normalized high-density lipoprotein cholesterol levels. Humatrope, Nutropin, and Nutropin AQ for long-term treatment of short stature associated with Turner's syndrome. Serostim is approved for the treatment of AIDS wasting (i.e., cachexia). Investigational: Short children due to intrauterine growth retardation.

Contraindications: In clients in whom epiphyses have closed. Active intracranial lesions, sensitivity to benzyl alcohol (somatrem); sensitivity to m-cresol or glycerin (diluent in Humatrope). Use of Genotropin to treat acute catabolism in critically ill clients. NOTE: Hypothyroidism (which may be induced by the drug) decreases the response to somatrem.

Special Concerns: Use with caution during lactation. Concomitant use of glucocorticoids may decrease the response to growth hormone.

Side Effects: Development of persistent antibodies to growth hormone (30%-40% taking somatrem and 2% taking somatropin). Development of insulin resistance; hypothyroidism. Sodium retention and mild edema (especially in adults). Slipped capital femoral epiphysis or avascular necrosis of the femoral head in children with advanced renal osteodystrophy. Intracranial hypertension manifested by papilledema, visual changes, headache, N&V.; In adults: Hyperglycemia, glucosuria; mild, transient edema; headache, weakness, muscle pain. In children: Injection site pain, leukemia.
Nutropin AQ: CTS, increased growth of preexisting nevi, gynecomastia, peripheral edema (rare), pancreatitis (rare). Somatropin: In adults, headache, localized muscle pain, weakness, mild hyperglycemia, glucosuria, mild transient edema during early treatment.

Overdose Management: Symptons: In acute overdose, hypoglycemia followed by hyperglycemia. Long-term overdose can result in S&S; of acromegaly or gigantism.

Drug Interactions: Glucocorticoids inhibit the effect of somatrem on growth.

How Supplied: Somatrem: Powder for injection: 5 mg, 10 mg; Somatropin: Injection: 5 mg/mL; Powder for injection: 1.5 mg, 5 mg, 5.8 mg, 6 mg, 10 mg

Dosage
Somatrem (Protropin) ?IM, SC
Individualized. Usual: Up to 0.1 mg/kg (0.26 IU/kg) 3 times/week, not to exceed a weekly dosage of 0.30 mg/kg (about 0.90 IU/kg). The incidence of side effects increases if the dose is greater than 0.1 mg/kg.
Somatropin (Genotropin) ?SC
0.16-0.24 mg/kg/week divided into 6 or 7 SC injections.
Somatropin (Humatrope) ?IM, SC
Adults: Individualized. lnitial: 0.006 mg/kg/day (0.018 IU/kg/day) or less SC. May be increased, depending on need, to a maximum of 0.0125 mg/kg/day (0.0375 IU/kg/day). Pediatric: 0.18 mg/kg/week (0.54 IU/kg/week) SC or IM divided into equal doses given either on 3 alternate days or 6 times a week. Maximum weekly dose is 0.3 mg/kg (0.9 IU/kg) divided into equal doses and given on 3 alternate days.
Somatripin (Norditropin) ?SC
0.024-0.034 mg/kg 6 to 7 times a week.
Somatropin (Nutropin, Nutropin aq) ?SC Growth hormone deficiency.
Individualized. Usual: Give a weekly dose of 0.3 mg/kg (about 0.9 IU/kg).
Chronic renal insufficiency.
Individualized. Usual: Give a weekly dose of 0.35 mg/kg (about 1.05 IU/kg). This dose can be given up to the time of renal transplantation.
Turner Syndrome.
Give a weekly dose of 0.375 (or less) mg/kg (about 1.125 IU/kg) divided into equal doses 3 to 7 times/week.
Somatropin (Saizen) ?IM, SC
0.06 mg/kg (about 0.18 IU/kg) 3 times weekly. Discontinue when epiphyses fuse.
Somatropin (Serostim) ?SC
Weight > 55 kg: 6 mg daily; 45-55 kg: 5 mg daily; 35-45 kg: 4 mg daily; less than 35 kg: 0.1 mg/kg. Give daily dose at bedtime.