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Information relating to specific disease areas aligned to Pfizer’s portfolio and other resources designed for Pfizer medicines.

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Information on how to access Genotropin® (somatropin, rbe) prescribing information and adverse event reporting can be found at the bottom of the page.

The Genotropin pen has two dosage formats

Genotropin pen cartridges are available in two dosage presentations: 5.3mg and 12mg strengths.

  • Patients requiring a dose of under 0.5 mg/day should use the 5.3 mg pen
  • Patients requiring a higher dose should use the 12 mg pen

Please refer to the Genotropin Summary of Product Characteristics for information on dosing for different indications. 

Genotropin Pen – Easy to use and simple training

The Genotropin pen has been designed to help users introduce it into daily life using four easy steps each day.

  1. Attach the needle
  2. Press the red button
  3. Dial up a dose
  4. Give the injection

Patient demonstration videos

To help reinforce your training, Pfizer UK provides educational videos for patients to watch, giving step-by-step instructions on the preparation and use of the Genotropin Pen.

​​​​​​​These videos can be sent out to new patients as a DVD and as part of their starter pack, and can be reviewed below.

Watch how a child patient takes her Genotropin daily with the Pen

Watch this video of a teenage patient taking her daily Genotropin with the Pen

Training Guide for Genotropin Pen Use

A. Setting up the pen – inserting a cartridge​​​​​​​

This procedure should be followed by patients when setting up a Genotropin pen for the first time, or when replacing a cartridge.

  1. Instruct patients (or carers) to find and press the red button on the side of the pen, which releases the black injection button from its locked position.
  2. Now, remove the lid from the pen so that the cartridge holder can be unscrewed from the pen. If replacing an empty cartridge, once the holder has been removed, the cartridge can be unscrewed from the holder and discarded into a sharps bin.
  3. To reset the pen mechanism, instruct patients to gently turn the injection button anticlockwise until it cannot be turned any further. It should not be possible to see the plunger rod in the window at the front of the pen.
  4. The injection button should now be turned clockwise until it clicks, and the white mark on the injection button is aligned with the grey mark on the pen.
  5. The pen is now ready to have the needle attached.

B. Attaching the needle

  1. Instruct users to remove the foil from a fresh needle unit, and attach it to the cartridge holder by pushing and screwing it on. Make sure that patients are aware that the needle cap should be kept on at this stage.
  2. On taking out a new cartridge, users should check that the number of milligrams and the colour match those of the pen.
  3. With the cartridge holder upright, users should be instructed to insert the cartridge firmly, powder end first. Holding the pen with the needle pointing vertically upright, the two parts of the pen can then be screwed together.

C. Mixing the somatropin growth hormone with solvent

​​​​​​​​​​​​​The Genotropin comes in two parts: a liquid solvent and powdered growth hormone which need to be mixed together before use. This should happen automatically on screwing the cartridge into place. To check that this has occurred satisfactorily:

  1. Users should check the cartridge window to see that the solvent and powder have mixed fully and that the powder is properly dissolved. If further mixing is required, the pen should be tipped gently from side to side without shaking.

  2. Users should also check that the dissolved product appears ‘clear’. If the appearance of the solution is cloudy, the medicine should not be used and must be safely discarded in their sharps bin.  Users should then simply replace the faulty cartridge with a new one and contact their doctor or nurse.

D. Removing the air from the pen.

  1. Users should take off the outer needle cover and put it in a safe place; next they should remove the inner needle cover and discard it in the sharps bin. Caution patients that the needle needs to be kept sterile and is sharp, so care must be taken.
  2. Advise patients to hold the pen in a vertical position and gently tap the top of the pen and watch for air bubbles. Once all air bubbles have risen, they should press the black and white injection button fully so that a small amount of liquid is ejected.  If no liquid emerges, press the red release button, turn the injection button one click clockwise, and press the injection button again. Repeat if necessary, until some liquid has emerged. Once the air has been successfully removed, the pen is loaded and ready for use on a day-to-day basis.

E. Preparing for the daily injection

Before injecting, patients should remove the outer needle cover and place it on one side safely for later use. The inner needle cover can now be removed and discarded in the sharps bin.

  1. Patients should now remove any excess air, as described in point ‘D’ above. The pen is now ready for injection.

If using a needle guard, this can be added at this point to the Genotropin pen. The needle guard will hide the needle from view during an injection and can be used for each injection for the lifetime of the pen.

  1. First patients should press the red release button on the side of the pen to release the injection button and switches on the dose display.
  2. To set the dose, users should turn the injection button clockwise until the correct dose appears on the display.

F.  Injecting the Genotropin

  1. To inject, advise patients or their carer to push the pen straight down into the skin at an injection site that has been prepared in accordance with healthcare provider instructions.
  2. Patients should use their thumb to push the injection button down until it clicks in the locked position, and should count for 10 seconds before the needle is pulled straight up out of the skin.​​​​​​​​​​​​​​

G. Removing the needle

If using a needle guard, this should be removed first and prior to attempting needle removal.

  1. Using the outer needle cap, push the cap onto the end of the cartridge holder so that it covers the needle.
  2. Whilst squeezing the sides of the cap twist the needle anticlockwise to unscrew it.  The needle will stay inside the needle cap, and the cap and needle should be safely disposed of in the sharps bin.
  3. Patients should then replace the Genotropin pen lid, before replacing the pen in its box and storing the pen in the refrigerator until the next dosage.

Explore more

NICE technology appraisal guidance

Find out more about NICE’s technology appraisals on the use of somatropin

Find out more

Endocrine helpline 

Our dedicated nurse team are on hand to support patients being treated with Genotropin and healthcare professionals who have Genotropin patients

Contact the team

The Pen

Find out more about the Pen device

Visit the Pen page

Support for Pharmacists

If you’re a pharmacist and want to know more about Genotropin 

Click here

Turner Syndrome

Watch Dr Helen Turner talk about the early diagnosis of Turner syndrome, the commonest chromosomal disorder in women 

Find out more 

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PP-PFE-GBR-2688. December 2020