The growth hormone stimulates tissue growth, linear growth (height), and protein, carbohydrate, lipid, and mineral metabolism.
Somatropin is the synthetic form of growth hormone, which is a protein that is made to be nearly the same as the main form of growth hormone which is naturally produced in the body.
It is used for the long-term treatment of children with growth failure due to a lack of secretion of endogenous growth hormone. It is also used for long-term replacement therapy in adults with growth hormone deficiency in either childhood or adult-onset.
There are a lot of brand names for somatropin, such as Omnitrope, Genotropin, Humatrope, Norditropin, and Nutropin.
The main point to remember is the device is different but the medication is the same.
Why do I need this growth hormone replacement?
Growth hormone deficiency happens when the pituitary gland does not make enough growth hormone. Its diagnosis is based on the combination of pituitary disease, hypopituitarism (when you have a deficiency in one or more pituitary hormones), and a decrease in the concentration of insulin-like growth factor I (IGF-I). It can also be diagnosed through a low growth hormone response to stimuli during a dynamic test, for example, the insulin stress test.
What are the benefits of growth hormone replacement?
The growth hormone stimulates tissue growth, linear growth (height), and protein, carbohydrate, lipid, and mineral metabolism. It decreases fat mass and risk of fractures and increases lean body mass, muscle strength, exercise performance, cardiac capacity, and bone mineral density.
Treatment aims to improve quality of life.
What are the risks of growth hormone replacement?
Common side effects include:
- joint stiffness
- arthralgia (joint pain)
- myalgia (muscle pain)
- paraesthesia (numbness, tingling or pricking, ‘pins and needles’, or a burning feeling in arms, hands,
legs or feet) - peripheral edema (build-up of fluid causing swelling, usually in lower limbs)
- some fluid retention (excess fluids build up inside your body)
- carpal tunnel syndrome (pressure on nerves of the wrist causing tingling, numbness, and pain in your hand
and fingers) - worsening of glucose tolerance (higher than normal blood glucose levels)
These hormonal side effects generally respond to dose reduction. Older and more obese patients are more prone to side effects from growth hormone treatment. There is no evidence that growth hormone replacement in adults increases the risk of new or recurrent malignancy (cancer that has come back).
Experts state that growth hormone replacements should not be used during pregnancy. It is generally stopped at the end of the first trimester (12 weeks) as the rise in placental growth hormone (at around 8 weeks) is felt to be the main determinant in maternal IGF-1.
Do I need to prepare for my clinic visit to start growth hormone replacement treatment?
There are no preparations needed. An endocrine nurse specialist will contact you to arrange a clinic visit.
What happens before my clinic visit?
Your endocrine doctor will discuss with you during an outpatient clinic visit if you need growth hormone replacement treatment. A doctor will then refer you to an endocrine nurse specialist to start the treatment.
What happens during my initiation for a growth hormone replacement visit?
Your endocrine nurse specialist will take your baseline hormone levels which include your IGF-1 levels, and teach you how to give yourself growth hormone injections.
You will need to sign a written consent form to start the treatment. A registration form and prescription form will be requested for you for homecare delivery of medication supply.
If you are unable to attend the growth hormone visit, verbal consent may be documented and nurse injection training can be given via healthcare at home service.
How long does the growth hormone replacement treatment take?
We will advise you to continue treatment for at least six to nine months. If therapy is tolerated, with a good clinical response to treatment then there is no reason to stop therapy, and treatment will be long-term. But if there is no perceived or biochemical benefit of treatment after at least one year of therapy, then stopping growth hormone replacement therapy may be appropriate.
How do I take the medication?
Growth hormone injections are taken daily, preferably at night time. It is injected via a subcutaneous route (injection under the skin into the fatty tissues). Common areas for injection are the upper outer area of the arm, the front and outer sides of the thighs, upper outer area of the buttocks and abdomen (except for a two-inch area around the navel).
You will need to rotate your injection sites to avoid trauma, inflammation, or infection at the site of injection.
Fixed grade phase
The fixed grade phase is the first three months of treatment.
You will be started on a 0.3mg injection daily dose for the first four weeks, titrate up to 0.4mg injection daily for the next four weeks, and titrate up to 0.5mg injection daily for the third month.
Individualized titration phase
The following three to six months will be the individualized titration phase, which ensures that a maintenance dose is achieved. The titration process will aim to reach the upper limit IGF-1 level age-related normal range and also consider any side effects or patient tolerance to treatment. Ideally, your IGF-1 levels will be monitored during the third, sixth, and ninth-month clinic visits, and then yearly after that.
If you miss a couple of doses due to forgetting to inject yourself, an accident at home, or poor storage of medication causing it to expire, take your usual dose on the following day when the medication is available. Do not overdose.
What happens after my growth hormone treatment?
Follow-up visits will vary depending on your response to treatment. Once a maintenance dose is reached, you will usually be reviewed every year for both IGF-1 levels and checking for any side effects.
Contact our team of medical experts to ask for a free consultation.