I think what your mum would need is to have an endoscopy to determine what is causing the ulcers. you can try dr. devani at the aga khan in nairobi but may be other wazuans can recommend other (cheaper) doctors.
nexium (20g and 40g) would be good for the meantime until doctor advises appropriate treatment
ps. i am not a doctor so i am not providing medical advice, just some fire fighting advice
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