13. Gastrointestinal system

Infection	IV treatment	Oral treatment	Total duration
Severe gastroenteritis requiring hospital admission cause unknown +	Do not use until established diagnosis or patient seriously ill Ciprofloxacin 200 - 400mg bd*	Ciprofloxacin 500mg bd	3 to 5 days
Invasive Salmonellosis	Ciprofloxacin 200 - 400mg bd*	Ciprofloxacin 250 - 500mg bd or Trimethoprim 200mg bd	14 days
Enteric Fever (Typhoid)	Ciprofloxacin 200 - 400mg bd* or Cefotaxime 1g bd or Chloramphenicol 50mg/kg/day* in four divided doses	Ciprofloxacin 250 - 500mg bd or Chloramphenicol 50mg/kg/day in four divided doses.	14 days
Severe Campylobacter Enteritis		Clarithromycin 500mg bd or Ciprofloxacin 250 -	3-5 days
Bacillary  Dysentry	Antibiotic not usually recommended in Shigella sonnei infections Severe infections - treat as for invasive salmonellosis
Biliary Tract Infection (cholecystitis / cholangitis)	Tazocin 4.5g tds* plus gentamicin (See protocol for dose. Monitor levels) or Ciprofloxacin 200 - 400mg bd* plus metronidazole 500mg tds N.B. prolonged IV therapy may be necessary due to compromised oral absorption.	Ciprofloxacin 500mg bd plus / minus metronidazole 400mg tds	7-10 days
Infective pancreatitis	Tazocin 4.5g tds* plus gentamicin (if severe / no improvement) (See protocol for dose. Monitor levels) or Ciprofloxacin 200 - 400mg bd plus / minus metronidazole 400mg tds N.B. prolonged IV therapy may be necessary due to compromised oral absorption.	Ciprofloxacin 500mg bd plus / minus metronidazole 400mg tds	7-10 days
Peritonitis	Cefuroxime 750mg-1.5g tds* plus metronidazole 500mg tds plus / minus gentamicin (See protocol for dose. Monitor levels) or Tazocin 4.5g tds* if severe / no improvement plus gentamicin (See protocol for dose. Monitor levels) or Ciprofloxacin 200-400mg bd* plus metronidazole 500mg tds	Ciprofloxacin 500mg bd plus metronidazole 500mg tds	Once clinical improvement occurs oral antibiotics can be used for a further 7-10 days.
Diverticulitis	Cefuroxime 750mg - 1.5g TDS* plus metronidazole 500mg TDS	Co-amoxiclav 625mg TDS	IV treatment until clinical improvement usually up to 4 days then oral therapy for 7-10 days
Antibiotic Associated Colitis	If oral route not available metronidazole 500mg tds	Metronidazole 400mg tds See section 26 Seek advice if patient relapses	10 days

+N.B. Please be aware of other causes of diarrhoea such as Clostridium difficile (especially if recent antibiotic exposure - refer to section 26), E.coli 0157 or Norwalk virus
* For patients with renal impairment refer to section 23 for dosage adjustments

Condition	Treatment	Duration
Helicobacter eradication	First line use : Omeprazole 20mg bd orally plus amoxicillin 1g bd and clarithromycin 500mg bd orally	7 days
Helicobacter eradication Penicillin-	Omeprazole 20mg bd orally plus metronidazole 400mg bd and clarithromycin 500mg bd orally	7 days

Sensitivity testing has confirmed that the local area has a high prevalence of metronidazole-resistant Helicobacter.
 
The importance of completing the course should be emphasised to the patient - this treatment may transform subsequent management of the ulcer by preventing relapse and eliminating the need for long-term treatment. Information regarding side-effects should also be given.

N.B. Dual regimens are not now recommended, as eradication rates are much lower.
Consult a gastroenterologist if the latest information or clinical advice is required.