Gastric band adjustments

This information is for people who have been fitted with a gastric band.

A gastric band is an adjustable band around the upper part of your stomach. It limits and controls the amount of food you eat, to help with weight loss.

It is important we check and adjust your band in the months after surgery. This makes sure you have the best chance of losing weight.

Once you've fully recovered from surgery you will have your first adjustment. This is a very quick and simple procedure. It takes place during your outpatient appointments at St Thomas’ Hospital.

How gastric band adjustments work

A specially trained member of the bariatric team (the area of medicine that is about obesity) will do the gastric band adjustment. This is usually your dietitian, but might be a member of the surgical team.

You might have noticed that you can feel a small, hard object below one of your surgery scars. This is the injection port. 

Your band will be adjusted by adding or removing fluid through this port, making the band tighter or looser.

When you have your gastric band placed it will have very little or no fluid inside. At your first adjustment, fluid will be added to the band using a needle in your port. This makes the band tighter around your stomach.

You need a few of these adjustments before your band is tight enough to reduce hunger and leave you feeling full.

We inject fluid into the band in small amounts. This will avoid the problems you might have with an overtight band

People with an overtight band might have weight loss at first but will fail to lose weight in the long-term, and risk developing complications.

Making your band tighter

We might add fluid to your band if:

  • you are feeling hungry
  • you can eat larger portions
  • your weight loss has slowed down
  • you have gained weight

Making your band looser

We might remove fluid from your band if:

  • you cannot eat solid food
  • you are relying on liquid or sloppy foods
  • you regularly bring up food or fluid after swallowing (regurgitation) or have heartburn (discomfort caused by acid coming back up into food pipe)
  • you are coughing at night

How often you have adjustments

Your first band adjustment is usually 6 to 8 weeks after your gastric band surgery. 

You get a letter in the post with your appointment date and time.

We tailor adjustments to the band to your individual needs. Some people need a lot of adjustment to get their band just right. 

It's important to remember that the band will not work well if it is too loose or too tight. You might need a few adjustments (usually between 4 and 8, sometimes more) before your band is working properly. 

These appointments are usually every 6 to 8 weeks to get the band working as quickly as possible.

When you arrive at your appointment

When you arrive for your appointment, please go to the reception desk. Details of where you need to go will be in your appointment letter.

A nurse will call you and check your height and weight.

We take you to a clinical room where a member of the bariatric team will see you.

During your appointment

We ask you how you are getting on with your band. It is very important to answer the questions as honestly as you can. This means we can check how much your band needs to be adjusted.

Remember, that there is no judgement in the appointment. You can feel confident that all your experiences with your band will be dealt with in an empathetic way.

An adjustment does not always mean that your band will be tightened. Some people might need fluid to be taken out of their band. Others might need nothing, as their band is already working properly.

Most of the time, an anaesthetic is not needed for a band adjustment. You will only feel a very small scratch during the procedure.

  1. If an adjustment is needed, we clean around the port site with alcohol to make sure the area is free from germs.
  2. We find the correct place to put the needle by feeling your port site.
  3. We might ask you to raise your head or your legs up. This squeezes your stomach muscles together which will help to find your port.
  4. Once we locate your port, the needle is positioned.
  5. At your first band adjustment, we remove the air that is in the tube and band when it was first placed. 
  6. We add or remove fluid using the needle into your port.
  7. The whole procedure usually takes about 15 minutes.

After your gastric band adjustment

You have a glass of water, and a banana or yoghurt, after your band has been adjusted. This is to make sure that your band has not been overfilled. It is important that you have this before you leave hospital.

Please make sure you follow our food and drink instructions.

In the ideal zone for weight loss you should:

  • have satisfaction with small meals
  • feel full early and for longer
  • have satisfactory weight loss or maintenance


  • follow our eating and drinking guidance
  • take small bites and chew well before swallowing
  • eat slowly to let the food clear your band and to avoid food ‘backing up’ in your food pipe

    If your band is too tight after your adjustment

    The bariatric team will carefully adjust your band based on the assessment at the beginning of your appointment. This will make a noticeable, but manageable, change to your eating behaviours.

    Each person reacts differently to an adjustment. It is not possible to know exactly how much fluid a person needs in their band.

    On very few occasions, you might find that your band is too tight after an adjustment.

    It is important not to leave a tight band for too long, as this can lead to complications, such as:

    • a prolapse, where the stomach slips through the band
    • erosion of the band, where the band grows into the stomach

    Call the bariatric team straight away or go to A&E if:

    • swallowing is difficult (either drink or your own saliva)
    • you have heartburn
    • you bring food or fluid back up after swallowing often

    Resource number: 3578/VER2
    Last reviewed: May 2020
    Next review due: May 2023

    Contact us

    If you have any questions or concerns, contact the bariatric team.

    Phone: 020 7188 4128

    Email: [email protected]

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