Taking doxycycline hycl 100mg, oxybutynin 5mg. Ended up with yeast infection so added single dose fluconazole. Sour stomach/acid now. Can I add nexium to calm the stomach? I am a 56 yr old female, weighing 115lbs, no smoke/ drink. Set for MRI to determine kidney/bladder/urethra pain, history of kidney stones. Is there something else that would be natural, I don t often take meds. Thank you, Peri Ann