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Bowel preparation with Plenvu and oral antibiotics prior to bowel surgery

Patient information A-Z

RATIONALE: There is now increasing evidence that having an empty bowel and taking oral antibiotics prior to bowel surgery may reduce some of the risks of surgery, in particular wound infections. Please follow our advice carefully in order to prepare yourself properly for surgery. When taking these preparations some intestinal cramping is normal. If you feel clammy and faint or if you vomit please take no more preparation but do keep drinking plenty of clear fluids (see below). If you feel very unwell then do call your own GP for advice.

Legally we must enclose the pharmaceutical leaflets that come with the Plenvu; we are aware that our instructions differ slightly from these but we prefer you to follow our recommendations please.

Please double check that you are not known to be allergic to metronidazole or neomycin. Neither of these is a penicillin related medicine. If you are concerned please let us know in good time and do not take them until we are sure it is safe.

Seven days before taking the preparation

If you take iron tablets or medication to control diarrhoea (e.g. loperamide, codeine) please stop taking them until after your surgery. You should continue to take any other medication including medication for high blood pressure / cardiac conditions.

Three days before taking the preparation

You may eat your normal meals for the whole three days, but avoid high-fibre foods such as fruit, vegetables, wholemeal bread and All Bran (see below).

You may eat You should avoid
You may eat Cereals:
Cornflakes, Rice, Rice Krispies, Ricicles, Sugar Puffs and Coco Pops
You should avoid Wheat
bran, All Bran, Weetabix, Shredded Wheat, oat bran, bran flakes, wheat flakes,
muesli, Ready-Brek, porridge
You may eat White
bread (you may use butter / margarine)
You should avoid Wholemeal,
high-fibre white, soft grain or granary bread, oatbread
You may eat White
pasta, white rice
You should avoid Wholemeal
pasta, brown rice
You may eat White
You should avoid Wholemeal
or granary flour, wheatgerm
You may eat Potatoes
(no skin)
You should avoid Fruit
and vegetables
You may eat Savouries:
Chicken, turkey, fish, cheese and eggs
You should avoid All
red meat
You may eat Puddings,
pastries, cakes, milk puddings, mousse, jelly (not red), sponge cakes,
Madeira cakes, rich tea biscuits, wafer biscuits
You should avoid Foods
containing wholemeal flour, oatmeal, nuts, dried fruit, fruit cake, Ryvita,
digestives or hobnob biscuits
You may eat Preserve
and sweets: Sugar, jelly jam, jelly marmalade, honey, syrup, lemon curd
You should avoid Jam
or marmalade with pips, skins and seeds, sweets and chocolate containing nuts
/ fruit, muesli bars
You may eat Soup:
Clear or sieved soups
You should avoid Chunky
vegetable, lentil or bean soups
You may eat Miscellaneous:
salt, pepper, vinegar, mustard, salad cream, mayonnaise
You should avoid Nuts,
quorn, fresh ground peppercorns, hummus, anything
containing seeds

The day before the surgery

Taking other medication

Please note that other medicines should be taken at least one hour before taking Plenvu or at least one hour afterwards because they may be flushed through your digestive system and not work so well.

08:00 Eat breakfast avoiding food containing nuts, seeds or fruit.


13:00 Take the first dose of antibiotics (neomycin two 500mg tablets and metronidazole one 400mg tablet).

14:00 Take the first dose of Plenvu following the steps below:

  1. Empty the contents of ‘Dose 1’ into a measuring container that holds 500ml (0.9 pints) of fluid.
  2. Add water to make up to 500ml and stir until the powder has dissolved. This may take up to eight minutes.
  3. Drink all of the dissolved mixture over 30 minutes until you have drunk it all. There is no need to rush.
  4. A further 500ml of clear fluid must be drunk over the next 30 minutes. There is no need to rush.

**You will begin to pass frequent loose motions, please stay near a toilet at this time.**

17:00 Take the second dose of antibiotics (neomycin two 500mg tablets and metronidazole one 400mg tablet).

19:00 Follow the same steps as for 14:00 for the second dose of Plenvu. Use both ‘Dose 2 sachet A’ and ‘Dose 2 sachet B’

22:00 Take the third dose of antibiotics (neomycin two 500mg tablets and metronidazole one 400mg tablet).

If you have been given Nutricia PreOp drinks by the pre-assessment nurse please drink four (4) bottles during the evening before your operation, and on the day of your operation drink two (2) bottles in the morning, to be finished by 06:00.

You should continue to drink ‘clear’ fluids up until 06:00. Acceptable fluids include:

  • Water / flavoured water
  • Clear soup, for example consommé that contains no solids.
  • Fruit juice without pulp, for example orange or lemon squash that is diluted (not red or purple in colour)
  • Clear fizzy drinks, for example lemonade, Lucozade, tonic water, cream soda, soda water
  • Bovril / Oxo
  • Lime cordial
  • Herbal teas (no milk)
  • Clear apple juice or white grape juice
  • Jelly (without fruit pieces)

06:00 No more fluids by mouth. Depending on the timing of your surgery you may be allowed to drink more water before your operation when you are in the pre-operative area in L2 DSU.

**You may find that a small amount of vaseline / sudocrem applied to your back passage (anus) prevents discomfort during the bowel preparation. Some intestinal cramping is normal but if you feel clammy and faint or if you vomit please take no more preparation. Do keep drinking clear fluids until 06:00 and come into hospital as planned.**

Contacts / Further information

If you have any further questions or concerns, please contact Addenbrooke’s Pre-Operative Assessment on telephone 01223 250888, Monday to Friday 08:30 – 17:00. If you have any urgent concerns outside these hours please contact your GP surgery.

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Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151