nausea; Feeling lousy; Increased shortness of breath; diarrhea; Hypotension; Fatigue; Weakness since starting Tyvaso; Irritable bowel syndrome; This is a spontaneous report received from non-contactable reporter(s) (Consumer or other non HCP). The reporter is the patient. Other Case identifier(s): UNT-2021-020346.  A 89 year-old female patient received bnt162b2 (BNT162B2), administration date 06Oct2021 (Batch/Lot number: unknown) at the age of 89 years as dose 3 (booster), single for covid-19 immunisation; treprostinil sodium (TYVASO), administration date 06Oct2021 (Lot number: 2102027, Expiration Date: 30Nov2022) as unk, 4x/day (18-54 ug, qid) and administration date 2021 (Lot number: 2102030, Expiration Date: 30Nov2021) as 4x/day (18-72 ug, qid) for pulmonary arterial hypertension. Relevant medical history included: "Pulmonary arterial hypertension" (ongoing). Concomitant medication(s) included: TADALAFIL; XARELTO. Vaccination history included: Bnt162b2 (DOSE 1,SINGLE), for Covid-19 immunization; Bnt162b2 (DOSE 2,SINGLE), for Covid-19 immunization. The following information was reported: NAUSEA (non-serious) with onset Oct2021, outcome "unknown", described as "nausea"; FEELING ABNORMAL (non-serious) with onset Oct2021, outcome "unknown", described as "Feeling lousy"; DYSPNOEA (non-serious) with onset Oct2021, outcome "unknown", described as "Increased shortness of breath"; DIARRHOEA (non-serious) with onset Oct2021, outcome "unknown", described as "diarrhea"; HYPOTENSION (non-serious) with onset Oct2021, outcome "unknown", described as "Hypotension"; FATIGUE (non-serious) with onset Oct2021, outcome "unknown", described as "Fatigue"; ASTHENIA (non-serious) with onset Oct2021, outcome "unknown", described as "Weakness since starting Tyvaso"; IRRITABLE BOWEL SYNDROME (non-serious) with onset 2021, outcome "unknown", described as "Irritable bowel syndrome". The action taken for treprostinil sodium was unknown.  Additional information: On an unreported date in Oct2021, the patient experienced the events of occasional diarrhea (diarrhea), hypotension (hypotension), fatigue (fatigue) and weakness since starting Tyvaso (asthenia). Start date of IH Tyvaso was updated as 06Oct2021 (01Oct2021 previously reported). On an unreported date in Oct2021, within 8 days after initiating IH Tyvaso, the patient had a covid vaccine shot and started IH Tyvaso on 06Oct2021, then she had increased severe shortness of breath for 2 days, had slight shortness of breath higher than her baseline now, she had occasional diarrhea, had hypotension, fatigue, and weakness since starting IH Tyvaso. On an unreported date in 2021, the patient experienced the event of irritable bowel syndrome (irritable bowel syndrome). An additional dosage regimen of 18-72 µg (3-12 breaths), QID via IH route was added to Tyvaso. The patient had diarrhea (diarrhoea, previously reported) and feels more tired (fatigue, previously reported) since starting IH Tyvaso, but also got COVID booster around this time, had irritable bowel syndrome. The reporter's causality for the events diarrhoea, hypotension, fatigue, asthenia and dyspnoea with IH Tyvaso was considered to be possibly related. The reporter did not provide causality for the event of irritable bowel syndrome.  No follow-up attempts are possible; information about lot/batch number cannot be obtained. No further information is expected.