Somatropin

Somatropin is a prescription medication used for treating the symptoms of growth hormone deficiency.

• Somatropin is available under the following different brand names: Genotropin, Genotropin Miniquick, Genotropin Pen 12, Humatrope, Norditropin FlexPro, Nutropin, Nutropin AQ NuSpin 20, Nutropin AQ NuSpin 10, Nutropin AQ NuSpin 5, Omnitrope, Saizen, Serostim, Zorbtive, Nutropin AQ Pen 20, Nutropin AQ Pen 10, Zomacton

Adult dosage

Injection powder for reconstitution

Genotropin Miniquick

• 0.2mg, 0.4mg, 0.6mg, 0.8mg, 1mg, 1.2mg, 1.4mg, 1.6mg, 1.8mg, 2mg

Genotropin

• 5mg, 12mg

Humatrope

• 5mg, 6mg, 12mg, 24mg

Nutropin

• 10mg

Omnitrope

• 5.8mg

Saizen

• 5mg, 8.8mg

Serostim

• 4mg, 5mg, 6mg

Zomacton

• 5mg, 10mg

Zorbtive

• 8.8mg

Injection solution

Norditropin FlexPro

• 5mg/1.5mL, 10mg/1.5mL, 15mg/1.5mL

Nutropin AQ NuSpin 20

• 20mg/2mL

Nutropin AQ NuSpin 10

• 10mg/2mL

Nutropin AQ NuSpin 5

• 5mg/2mL

Omnitrope

• 5mg/1.5mL, 10mg/1.5mL

Growth Hormone Deficiency

Adult dosage

Weight-based dosing

• Norditropin: Initiate at 0.004 mg/kg daily and may increase the dose according to individual patient requirements to up to 0.016 mg/kg daily  
• Nutropin or Nutropin AQ: Not to exceed 0.006 mg/kg/day SC initially for 6 weeks; may increase up to 0.025 mg/kg/day if patient below 35 years and up to 0.0125 mg/kg/day if patient above 35 years
• Humatrope: Not to exceed 0.006 mg/kg/day SC initially; may increase dose up to 0.0125 mg/kg/day maximum depending on response
• Genotropin or Omnitrope: Not to exceed 0.04 mg/kg/week SC initially divided into equal doses over 7 days; may increase the dose at 4-8 week intervals up to 0.08 mg/kg/week
• Saizen: Not to exceed 0.005 mg/kg/day SC initially for 4 weeks; may increase dose up to 0.01 mg/kg/day
• Zomacton: Initiate at 0.006 mg/kg/day SC; may increase the dose, not to exceed 0.0125 mg/kg/day; not recommended for obese patients due to increased likelihood of adverse reactions

Non-weight-based dosing

• 0.2 mg/day (0.15-0.3 mg/day range) SC initially; may increase dose every 1-2 months by 0.1-0.2 mg/day based on clinical response and/or serum IGF-I levels

Pediatric dosage

• Genotropin: 0.16 mg/kg to 0.24 mg/kg per week; divided into equal 6-7 SC doses/week  
• Humatrope: 0.18-0.3 mg/kg/week (0.026-0.043 mg/kg/day) SC; divided into equal 6-7 SC doses/week
• Norditropin: 0.17-0.24 mg/kg/week (0.024-0.034 mg/kg/day) SC; divided into equal 6-7 SC doses/week
• Nutropin and Nutropin AQ: 0.3 mg/kg/week SC weekly divided into equal daily doses
• Prepuberty: Not to exceed 0.7 mg/kg/week divided into equal daily doses
• Omnitrope
  • 0.16-0.24 mg/kg/week SC divided into 6-7 doses/week
  • Alternatively, 0.06 mg/kg/dose administered 3 days/week or 0.03 mg/kg/dose administered 6 days/week
• Saizen
  • 0.18 mg/kg/week SC/IM divided into equal doses
  • Alternatively, 0.06 mg/kg/dose administered 3 days/week or 0.03 mg/kg/dose administered 6 days/week

Zomacton: Up to 0.1 mg/kg SC 3 times a week

Short-bowel Syndrome

Adult dosage

Zorbtive

• 0.1 mg/kg/day SC (rotating injection sites to avoid lipodystrophy) for 4 weeks; may increase up to 8 mg/day maximum; treatment exceeding 4 weeks not studied

HIV-associated Wasting or Cachexia

Adult dosage

Serostim

• Serostim: 0.1 mg/kg/day SC at bedtime (rotating injection sites to avoid lipodystrophy) up to 6 mg/day; if at risk for side effects may administer 0.1 mg/kg every other day; if loss of body weight continues after 12 weeks re-evaluate for opportunistic infections or other clinical events; to avoid lipodystrophy rotate injection site; adjust the dose to manage side effects
• Alternatively:
• Weighing above 55 kg: 6 mg/day SC
• Weighing between 45-55 kg: 5 mg/day SC
• Weighing between 35-45 kg: 4 mg/day SC
• Weighing below 35 kg: 0.1 mg/kg/day SC

Small for Gestational Age

Pediatric dosage

Humatrope: 0.47 mg/kg/week SC divided into equal doses 6-7 days/week  

Genotropin, Omnitrope

• 0.48 mg/kg/week SC divided into equal doses 6-7 days/week
• Initial treatment with larger doses of somatropin (e.g., 0.48 mg/kg/week), especially in very short children (ie, height SDS less than –3), and/or older/ pubertal children; consider a reduction in dosage (e.g., gradually towards 0.24 mg/kg/week) if substantial catch-up growth is observed during the first few years of therapy
• Consider in younger SGA children (eg, below 4 years) (who respond the best in general) with less severe short stature (ie, baseline height SDS values between -2 and -3) to initiate treatment at a lower dose (eg, 0.24 mg/kg/week), and titrating the dose as needed over time; carefully monitor the growth response, and adjust the somatropin dose as necessary

Norditropin

• 0.47 mg/kg/week SC divided into equal doses 6-7 days/week (up to 0.067 mg/kg/day SC)
• In very short pediatric patients, HSDS less than -3, and older pubertal pediatric patients consider initiating treatment with a larger dose of Norditropin (up to 0.067 mg/kg/day); consider gradual dosage reduction if substantial catch-up growth is observed during the first few years of therapy
• Below 4 years of age with less severe short stature, baseline HSDS values between -2 and -3: Consider initiating at 0.033 mg/kg/day and titrate dose as needed

Chronic Renal Insufficiency

Pediatric dosage

• Nutropin, Nutropin AQ: Not to exceed 0.35 mg/kg/week divided into equal doses for 6-7 days; continue until the time of renal transplantation
• Short stature associated with Noonan syndrome

Pediatric dosage

• Norditropin: Up to 0.46 mg/kg/week (not to exceed 0.066 mg/kg/day) SC divided into equal doses 6-7 days/week  
• Growth failure with Prader-Willi syndrome

Pediatric dosage

• Genotropin: 0.24 mg/kg/week SC divided into equal doses for 6-7 daily injection  
• Omnitrope: 0.24 mg/kg/week SC divided into 6-7 daily injections
• Norditropin: Up to 0.24 mg/kg/week SC divided into equal doses 6-7 days/week (not to exceed 0.034 mg/kg/day)
• Short stature associated with Turner syndrome

Pediatric dosage

• Genotropin: 0.33 mg/kg/week SC divided into 6-7 days/week  
• Humatrope: 0.375 mg/kg/week divided into 6-7 days/week (Not to exceed 0.054 mg/kg/day SC)
• Norditropin: Up to 0.47 mg/kg/week SC divided into equal doses 6-7 days/week (up to 0.067 mg/kg/day)
• Nutropin and Nutropin AQ: Not to exceed 0.375 mg/kg/week SC divided into 3-7 days/week
• Omnitrope: 0.33 mg/kg/week SC divided into 6-7 daily injections/week

Idiopathic Short Stature

Pediatric dosage

• Genotropin: Not to exceed 0.35 mg/kg/week SC divided into 6-7 days/week  
• Humatrope: Not to exceed 0.053 mg/kg/day SC (0.37 mg/kg/week divided into 6-7 days/week)
• Norditropin: Up to 0.47 mg/kg/week SC divided into equal doses 6-7 days/week (not to exceed 0.067 mg/kg/day)
• Nutropin and Nutropin AQ: Not to exceed 0.3 mg/kg/week SC divided into 6-7 days/week
• Omnitrope: Not to exceed 0.47 mg/kg/week SC divided into 6-7 daily injections/week

Short Stature Homeobox-Containing Gene

Pediatric dosage

• Humatrope: 0.05 mg/kg/day SC (0.35 mg/kg/week divided into 6-7 days)

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

Common side effects of Somatropin include:

• pain, itching, or skin changes at the injection site,
• swelling,
• rapid weight gain,
• muscle or joint pain,
• numbness or tingling,
• stomach pain,
• gas,
• headache,
• back pain,
• cold or flu symptoms,
• stuffy nose,
• sneezing,
• sore throat, and
• ear pain.

Serious side effects of Somatropin include:

• hives,
• difficulty breathing,
• swelling of the face, lips, tongue, or throat,
• shortness of breath,
• coughing,
• new or increased snoring,
• pain in the knees or hips,
• walking with a limp,
• ear pain or warmth,
• swelling or drainage from the ear,
• numbness or tingling in the wrist, hand, or fingers,
• severe swelling or puffiness in the hands or feet,
• changes in behavior,
• vision problems,
• unusual headaches,
• changes in the shape or size of a mole,
• pain or swelling in the joints,
• severe pain in the upper stomach spreading to the back,
• nausea,
• vomiting,
• increased thirst,
• increased urination,
• dry mouth,
• fruity breath odor,
• severe headache,
• ringing in the ears,
• dizziness,
• vision problems,
• pain behind the eyes,
• extreme weakness,
• severe dizziness,
• weight loss,
• changes in skin color, and
• tiredness.

Rare side effects of Somatropin include:

• none 

This is not a complete list of side effects and other serious side effects or health problems that may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Somatropin has severe interactions with no other drugs.
• Somatropin has serious interactions with the following drug:
  • macimorelin
• Somatropin has moderate interactions with the following drugs:
  • albiglutide
  • atogepant
  • insulin aspart
  • insulin degludec
  • insulin degludec/insulin aspart
  • insulin detemir
  • insulin glargine
  • insulin glulisine
  • insulin inhaled
  • insulin lispro
  • insulin NPH
  • insulin regular human
  • isavuconazonium sulfate
  • liraglutide
  • maraviroc
  • metformin
  • nateglinide
  • tazemetostat
  • ubrogepant
• Somatropin has minor interactions with the following drugs:
  • budesonide
  • cortisone
  • deflazacort
  • dexamethasone
  • fludrocortisone
  • hydrocortisone
  • methylprednisolone
  • prednisolone
  • prednisone
  • triamcinolone acetonide injectable suspension

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns.

Contraindications

• Hypersensitivity to metacresol or glycerin (diluent)
• Hypersensitivity to benzyl alcohol
• Acute critical illness after open-heart surgery, abdominal surgery, or multiple accidental trauma, or those with acute respiratory failure due to the risk of increased mortality with use of pharmacologic doses of somatropin
• Active malignancy
• Pediatric patients with closed epiphyses
• Active proliferative or severe non-proliferative diabetic retinopathy
• Active malignancy, acute complications of open heart or abdominal surgery, multiple trauma, acute respiratory failure
• Pediatric patients with Prader-Willi syndrome who are severely obese, have a history of upper airway obstruction or sleep apnea or have severe respiratory impairment due to the risk of sudden death

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Somatropin?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Somatropin?”

Cautions

• Increased mortality reported among patients with acute critical illness due to complications following open-heart surgery, abdominal surgery or multiple accidental trauma, or those with acute respiratory failure; the benefit of treatment continuation should be weighed against potential risk (see Contraindications)
• Reports of sudden death after initiating therapy with somatropin documented in pediatric patients with Prader-Willi syndrome who had more than 1 of the following risk factors: severe obesity, history of upper airway obstruction or sleep apnea, or unidentified respiratory infection; male patients with more than 1 factors may be at greater risk than females
• Monitor blood glucose in patients with other risk factors (e.g., obesity, Turner syndrome, family history of diabetes mellitus [DM]) for glucose intolerance during therapy and adjust antidiabetic treatment, as needed; new-onset type 2 DM reported, monitor glucose levels periodically; doses of concurrent antihyperglycemic drugs in diabetics may require adjustment
• Intracranial hypertension (IH) with papilledema, visual changes, headache, nausea, and/or vomiting reported; symptoms usually occurred within the first 8 weeks after initiation of therapy; all reported cases, IH-associated signs and symptoms rapidly resolved after cessation of therapy or a reduction of the somatropin dose; perform funduscopic examination should be performed routinely before initiating treatment to exclude preexisting papilledema, and periodically thereafter
• Serious systemic hypersensitivity reactions (eg, anaphylactic reactions, angioedema) reported with postmarketing use of somatropin products; inform patients and caregivers that such reactions are possible and prompt medical attention should be sought if allergic reaction occurs
• Cases of pancreatitis reported; pediatric patients possibly at a greater risk compared to adults; published literature indicates that females who have Turner syndrome may be at greater risk than other pediatric patients receiving somatropin products; consider pancreatitis in patients who develop persistent severe abdominal pain
• When somatropin is administered SC at the same site over a long period of time, tissue atrophy may result; may avoid by rotating the injection site (see Administration)
• Somatropin increases growth rate and progression of existing scoliosis can occur in patients who experience rapid growth; monitor patients with a history of scoliosis for progression of scoliosis
• Slipped capital femoral epiphysis may occur more frequently in patients with endocrine disorders (including GH deficiency and Turner syndrome) or patients undergoing rapid growth; evaluate pediatric patients with the onset of a limp or complaints of hip or knee pain
• Not indicated for the treatment of non-GH deficient adults
• Serious and fatal adverse reactions including “gasping syndrome” can occur in neonates and infants treated with benzyl alcohol; “gasping syndrome” is characterized by central nervous system depression, metabolic acidosis, and gasping respirations
• When administering therapy to infants, reconstitute with normal saline, not the diluent provided; only one dose should be used per vial and the reconstituted product should be discarded after use
• Serum levels of inorganic phosphorus, alkaline phosphatase, parathyroid hormone, and IGF-1 may increase after therapy
• Somatropin-treated patients who have or are at risk for pituitary hormone deficiency(s) may be at risk for reduced serum cortisol levels and/or unmasking of central (secondary) hypoadrenalism; patients treated with glucocorticoid replacement for previously diagnosed hypoadrenalism may require an increase in their maintenance or stress doses following initiation of treatment; monitor for reduced serum cortisol levels and/or need for glucocorticoid dose increases in those with known hypoadrenalism
• Hypothyroidism
  • Undiagnosed/untreated hypothyroidism may prevent an optimal response to therapy, in particular, the growth response in pediatric patients
  • Patients with Turner syndrome have an inherently increased risk of developing autoimmune thyroid disease and primary hypothyroidism
  • In patients with GH deficiency, central (secondary) hypothyroidism may first become evident or worsen during somatropin treatment; consider periodic thyroid function tests and initiate or appropriately adjust thyroid hormone replacement therapy when indicated
  • Increased risk of neoplasms
  • There is an increased risk of malignancy progression with somatropin treatment in patients with active malignancy; any preexisting malignancy should be inactive and its treatment complete before instituting somatotropin; discontinue somatotropin if there is evidence of recurrent activity (See Contraindications)
  • An increased risk of a second neoplasm was reported in patients treated with somatotropins after the first neoplasm; intracranial tumors, in particular meningiomas, in patients treated with radiation to head for the first neoplasm, were the most common of these second neoplasms; in adult cancer survivors, risk of occurrence unknown; given the limited data available, carefully monitor patients under growth hormone therapy for progression or recurrence of the tumor
  • Owing to pediatric patients with certain rare genetic causes of short stature have an increased risk of developing malignancies, thoroughly consider the risks and benefits of starting treatment in these patients; monitor patients for increased growth, or potential malignant changes of preexisting nevi; any preexisting malignancy should be inactive and its treatment complete before instituting therapy with somatropin; discontinue somatotropin if there is evidence of recurrent activity
• Zorbtive
  • If moderate fluid retention, arthralgia, treat symptomatically or reduce dose by 50%
  • Discontinue up to 5 days if severe toxicity, then restart at 50% dose; permanently discontinue if severe toxicity recurs or does not disappear within 5 days
• Drug interactions overview
  • Microsomal enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD-1) is required for conversion of cortisone to its active metabolite, cortisol, in hepatic and adipose tissue; somatotropin inhibits 11βHSD-1; individuals with untreated GH deficiency have relative increases in 11βHSD-1 and serum cortisol; initiation of somatotropin may result in inhibition of 11βHSD-1 and reduced serum cortisol concentrations
  • Pharmacologic glucocorticoid therapy and supraphysiologic glucocorticoid treatment may attenuate the growth-promoting effects of somatotropin in pediatric patients
  • Limited published data indicate that somatropin treatment increases CYP450 mediated antipyrine clearance; somatotropin may alter the clearance of compounds known to be metabolized by CYP450 liver enzymes
  • Oral estrogens may reduce the serum IGF-1 response to somatotropin
  • Treatment with somatotropin may decrease insulin sensitivity, particularly at higher doses

Pregnancy and Lactation

• Limited available data with somatropin use in pregnant women are insufficient to determine a drug-associated risk of adverse developmental outcomes
• In animal reproduction studies, there was no evidence of fetal or neonatal harm when pregnant rats were administered SC somatotropin during organogenesis or lactation at doses ~10-times higher than the maximal clinical dose of 0.016 mg/kg, based on body surface area
• The diluent contains benzyl alcohol, which has been associated with gasping syndrome in neonates; the preservative benzyl alcohol can cause serious adverse events and death when administered intravenously to neonates and infants; if therapy is needed during pregnancy, reconstitute with normal saline, use only one dose per vial, and discard reconstituted product after use, or use a benzyl alcohol-free formulation.
• Lactation
  • There are no data on the presence of somatropin in human milk; limited published literature reports no adverse effects on breastfed infants with maternal administration of somatropin; no decrease in milk production or change in milk content during treatment with somatropin reported; developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for somatotropin and any potential adverse effects on the breastfed infant from therapy or underlying maternal condition
  • The diluent contains benzyl alcohol; if therapy is needed during lactation, reconstitute with normal saline, use only one dose per vial, and discard after use or use a benzyl alcohol-free formulation.