Antisecretory drugs (PPIs and H2R blockers) can lead to false-negative results on a urea breath test. They interfere with H. pylori activity. Possible explanations include antibacterial property or pH-dependent urease activity. Therefore, PPIs or H2R blockers should be stopped 2 weeks before UBT.

1. Effect of H2R blockers on
Urea Breath Test (UBT)
D R . D H R I T I G U P T A , M B B S
E C F M G C E R T I F I E D
C L I N I C A L E X T E R N
J C M E D I C A L C E N T E R , F L O R I D A
U N D E R S U P E R V I S I O N O F D R . G . J E A N - C H A R L E S
N O V 1 8 , 2 0 2 1

2. Influence of
Antisecretory drugs on
UBT
April 2009
Conclusion:
1. False negative are seen in patients
taking pantoprazole or ranitidine.
2. Duration of therapy does not effect
the results.
60
H. pylori+
27
Pantoprazole
Day 14 6/27
Day 28 3/25
33
Ranitidine
Day 14 2/32
Day 28 2/32
Day 60 2/21
Oztürk E, Yeşilova Z, Ilgan S, Ozgüven M, Dağalp K. Performance Of Acidified 14c-urea Capsule Breath Test During Pantoprazole And Ranitidine Treatment. J Gastroenterol Hepatol. 2009;24(7):1248-1251. Doi:10.1111/J.1440-1746.2009.05845.X
False
negative or
equivocal
Repeat UBT
300 mg.
o.d.

3. Low
sensitivity of
UBT & stool
antigen test
• Conventional dose of PPIs
• High-dose of H2R blockers.
Gastric acid
suppression
• Direct antimicrobial effect on H pylori
or
• pH dependent suppression of urease
activity.
Why?
Level of Gastric Acid
Suppression is proportional
to false negativity of UBT.
Withhold antisecretory
drugs for 7-14 days.

4. Medications to avoid prior to UBT
4 weeks
• Antibiotics
• Bismuth
subsalicylate
2 weeks
• 3. PPI
• 4. H2R
blockers

5. HARRISON'S PRINCIPLES OF INTERNAL MEDICINE (19TH ED) (VOLS 1+2)(MEDGAG.COM)

6. Other Diagnostic tests for H. pylori
1. Urea breath test
◦ Juice
◦ Tablet/capsule
◦ 13C or 14C
2. Stool antigen test
Also influenced by PPIS and H2R blockers
3. Serology
Diagnostic test only.
Must not be used for Prognosis.

7. USU.EDU KNOWLEDGE BANK

8. Thank You