This prospective pregnancy case was reported by a consumer and described the occurrence of drug ineffective in a female patient who received GAVISCON Extra Strength tablet (batch number UNK, expiry date unknown) for heartburn. Co-suspect products included TUMS unknown (batch number UNK, expiry date unknown) for heartburn. On an unknown date, the patient started GAVISCON Extra Strength at an unknown dose and frequency and TUMS at an unknown dose and frequency. The patient's last menstrual period was on an unknown date and estimated date of delivery was on an unknown date. The patient received GAVISCON Extra Strength during the third trimester of pregnancy. On an unknown date, an unknown time after starting GAVISCON Extra Strength and TUMS, the patient experienced drug ineffective and drug exposure during pregnancy. The action taken with GAVISCON Extra Strength was unknown. The action taken with TUMS was unknown. On an unknown date, the outcome of the drug ineffective and drug exposure during pregnancy were unknown. The pregnancy was ongoing. The reporter considered the drug ineffective to be related to TUMS. Additional information: Consumer reported using GAVISCON Extra Strength Tablets, no lot code and expiration date was provided. Consumer reported drug exposure during pregnancy and off label use stated her doctor recommended that she tried your product, and she was so glad she did. Within minutes of trying your extra-strength tablets, she had complete and total relief from her heartburn. GAVISCON had been a miracle drug for her during this pregnancy. Consumer also reported drug ineffective and drug exposure during pregnancy stated she would never bother with those useless TUMS again. No further information was provided. Follow up information was received on 01June2017. Consumer reported that, "I am thirty weeks pregnant, and the baby due on 09 August 2017." I started to use the product when I was about ten weeks pregnant, and I had been using it, as needed, ever since". Follow up information was received on 07June2017. The consumer's address and contact details were updated. Follow up information was received on 20 September 2017 via returned consumer authorization form. Physicians address details were added to the case. Also It was reported that, "Normal healthy pregnancy. Induced labor began. Delivered via emergency C-section due to maternal distress from Amniotic fluid embolism. The pregnancy outcome as per follow up information would be retrospective. The events of C-section, Amniotic fluid embolism and live birth added to the case. It was unknown if the reporter considered the C-section, Amniotic fluid embolism and live birth to be related to TUMS and GAVISCON extra strength. The outcome of the events C-section, Amniotic fluid embolism and live birth was unknown. The case seriousness also upgraded case was changed from non serious to serious (medically significant). Pregnancy Note: November 6, 2017 No additional information was received, so this patient was considered lost to follow-up. Follow up information was received on 3 November 2017 via Pregnancy Outcome Form by midwife. The midwife details were updated in the case. The demographic details of patient were updated in the case (date of last menstrual period). The pregnancy information was updated in the case (delivery type - Cesarean, pregnancy outcome - Live Infant No apparent CA from lost to follow up, birth weight of neonate). The start and stop date of event C-section was updated. The outcome of events C-section, Amniotic fluid embolism and maternal distress was updated as recovered/resolved. The reporter considered the C-section, Amniotic fluid embolism, and maternal distress to be not related to TUMS and GAVISCON extra strength. The causality of events C-section, Amniotic fluid embolism and maternal distress was updated as No. Follow up information was received from physician on 29th November 2017: This case is now medically confirmed. The information was updated from the pregnancy outcome form. The last menstrual period date (LMP) was updated to 2nd November 2016 on the basis of provided estimated delivery date (EDD) 9th August 2017. The LMP was reported as 16th October 2017 which was discrepant. The patient received concomitant hydroxyzine for pruritus (at 39 weeks of pregnancy). On 18th May 2017, at 28 weeks and 1 day of pregnancy, the patient received BOOSTRIX (batch number ZN937, expiry date 7th May 2019) intramuscularly. 84 days after receiving BOOSTRIX, the patient gave birth to an unknown gender baby via emergency C-section delivery due to maternal distress from amniotic fluid embolism. These events were associated with complications of the pregnancy. The diagnosis was during the surgery (section). No lab test confirmed amniotic fluid embolism. The events were resolved. The reporter did not feel the GAVISCON in any way caused her amniotic fluid embolism. It was unknown if the reporter considered C-section, maternal distress and amniotic fluid embolism to be related to BOOSTRIX.