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Top tip one

Keep a register of bariatric surgery patients and record the type of procedure in the register

  • It is important to record the type of procedure in the register, as the different procedures have different risks of nutritional deficiencies. This is also essential information to include when liaising with specialist services

Top tip two

Encourage patients to check their own weight regularly and to attend an annual BMI and diet review with a healthcare professional

  • Do not assume that all patients are eating a well-balanced diet. Some may have maladaptive eating patterns and poor nutritional intake. If BMI is increasing, consider referral to local weight management services to support and encourage lifelong weight maintenance

Top tip three

Symptoms of continuous vomiting, dysphagia, intestinal obstruction (gastric bypass) or severe abdominal pain require emergency admission under the local surgical team

  • Further details of both urgent and routine indications for referral back to specialist services are summarised in poster formathere

Top tip four

Continue to review comorbidities post surgery, including diabetes, hypertension, hypercholesterolaemia and obstructive sleep apnoea, as well as mental health

  • Medication doses will need to be titrated in the postoperative period as weight loss occurs, but they may increase later if weight loss is not maintained
  • People with diabetes should also continue to have routine diabetes follow-up even if their diabetes goes into remission
  • Regardless of weight loss, cardiovascular and metabolic risk factors, such as blood pressure and cholesterol levels, must continue to be monitored, and treatments will need to be adjusted as required
  • Patients receiving continuous positive airway pressure should continue to use their machines until they have had a repeat sleep study performed post-surgery
  • There is a higher rate of mental health problems in people with severe and complex obesity compared with the general population and these problems may persist even after successful bariatric surgery. Therefore, mental health should be reviewed regularly following surgery. The psychological management of these people can be complex and, therefore, there should be a low threshold for referral to specialist mental health services

Top tip five

Review the patient’s regular medications

  • The formulations may need adjusting post-surgery to allow for changes in bioavailability. This is particularly relevant in people who undergo gastric bypass or duodenal switch. It is crucial that medications for comorbidities are closely monitored and adjusted as discussed in top tip four
  • Other medication considerations:
    • review comorbidity medications, such as antihypertensives, diabetes medications, etc., post-surgery. Requirements are likely to fall with postoperative weight loss, but may increase later if weight loss is not maintained
    • consider pill size—patients may need liquid formulations or syrups in the immediate postoperative period. However, usual medication formulations should be tolerated by around 6 weeks postoperatively
    • replace extended-release formulations with immediate-release formulations
    • psychiatric medications may need increased or divided doses
    • use diuretics with caution due to the increased risk of hypokalaemia
    • monitor anticoagulants carefully
    • avoid non-steroidal anti-inflammatory drugs; if no alternative, use only with a proton pump inhibitor
    • avoid bisphosphonates
    • patients with gastric bands should avoid effervescent medications

Top tip six

Bariatric surgery patients require lifelong annual blood tests, including micronutrient monitoring

  • Encourage patients to attend their annual blood tests. Use patient record reminders as a prompt
  • An annual audit of patient monitoring is recommended to ensure that correct follow-up is being performed
  • Recommended tests include:
    • liver function tests
    • full blood count
    • ferritin
    • folate
    • vitamin B12—if the patient is having 3-monthly intramuscular injections of vitamin B12, there may be no need for annual checks
    • calcium
    • vitamin D
    • parathyroid hormone
    • vitamin A:
      • if patient has had a duodenal switch
      • if the patient has had a long-limb bypass or has symptoms of steatorrhoea or night blindness following a gastric bypass
    • zinc, copper:
      • if patient has had a gastric bypass or duodenal switch
      • if the patient has had a sleeve gastrectomy, measure if there are deficiency concerns
    • selenium—only measure if there are deficiency concerns
  • People who undergo gastric banding require annual full blood counts, urea and electrolyte tests, and liver function tests, but these should be carried out earlier if there are any concerns regarding the band

Top tip seven

Be aware of potential nutritional deficiencies that may occur and their signs and symptoms

  • For further details on signs and symptoms, please refer to the full guideline
  • Liaise with the local Tier 3 or 4 specialist unit regarding any deficiencies and their treatment
  • In particular, patients are at risk of anaemia and vitamin D deficiency, as well as protein malnutrition and other vitamin and micronutrient deficiencies
  • If a patient is deficient in one nutrient they are likely to be deficient in others as well, so it is advised to screen for these
  • Clinicians should be aware of the potential nutritional deficiencies, such as:
    • protein malnutrition
    • anaemia
    • calcium and vitamin D deficiency
    • vitamin A deficiency
    • zinc, copper, and selenium deficiency
    • thiamine deficiency

Top tip eight

  • Patients will need lifelong supplements, and guidance should have been given by the bariatric unit on discharge, as the supplementation required depends on both the procedure and the patient’s individual requirements
  • If guidance on supplements has not been given on discharge, we would advise clinicians to always liaise with the Tier 4 bariatric unit in the first instance
  • Typical minimal supplements required after bariatric surgery:
    • gastric band—although no supplements should be needed for this group of patients, it is still recommended that they take a comprehensive multivitamin and mineral supplement once a day
    • gastric bypass or sleeve gastrectomy:
      • multivitamin and mineral supplement
      • vitamin B12 injections every 3 months
      • calcium and vitamin D, plus additional vitamin D as required
      • iron (start at 200 mg once daily and monitor as the dose may need to be increased), especially for women of menstruating age
    • duodenal switch:
      • as for gastric bypass, but additional fat-soluble vitamins (A, D, E and K) are also needed, as well as, possibly, zinc and copper; liaise with specialist local services for advice regarding these supplements

Top tip nine

Discuss contraception—ideally pregnancy should be avoided for at least 12–18 months post-surgery

  • A long-acting, reversible contraceptive of the patient’s choice would be appropriate. Oral contraception and i.m. medroxyprogesterone are not recommended because of issues with absorption and weight gain, respectively

Top tip ten

If a patient should plan or wish to become pregnant after bariatric surgery, alter their nutritional supplements to one suitable during pregnancy

  • Additional monitoring and supplementation may be required. Inform the local bariatric unit (ideally prior to conception) so that the patient can be reviewed by a bariatric dietitian. In addition, people who undergo gastric band surgery may need their band adjusting on becoming pregnant to allow good nutritional intake and foetal growth
  • The obstetric team should also be informed of the patient’s history of bariatric surgery as soon as possible, as there may be a higher rate of first trimester miscarriages in this cohort of patients
  • Recommended changes to treatment before and during pregnancy are as follows:
    • change nutritional supplement to one that is appropriate in pregnancy
    • if a proton pump inhibitor is needed, omeprazole is recommended
    • continue vitamin D supplementation as indicated by vitamin D levels (see NOS Vitamin D guideline)
    • continue vitamin B12 injections in those currently receiving them, or monitor levels in those not receiving them (for sleeve gastrectomy patients)
    • once-daily iron 200 mg is recommended
    • once-daily folic acid 5 mg is recommended

Further information

  • The printable short leaflet and extended versions of the ten top tips guidance are available on the RCGP nutrition web pages, together with the poster outlining referral criteria for post-surgery complications.
  • The short leaflet is available at: www.bit.ly/1zzyfxp
  • The extended version is available at: www.bit.ly/1wVfNl3
  • The poster outlining both urgent and routine indications for referral back to specialist services is available at: www.bit.ly/1Ddt6yT
  • The RCGP audit toolkit is available at: www.bit.ly/1Osurov


Full guideline:


Parretti HM, Hughes CA, O’Kane M, Woodcock S, Pryke RG. Ten Top Tips for the management of patients post-bariatric surgery in primary care. British Journal of Obesity 2015; 1: 68–73.

First included: January 2015.


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