SESSION TITLE: Medical Student/Resident Allergy and Airway Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Calendula officinalis, the common marigold, is a plant which has been ascribed a range of applications in traditional medicine, in both topical and oral forms, for the treatment of pain, superficial infections, and as a wound salve. We present a case of severe respiratory failure as a consequence of an asthma exacerbation in response to exposure to this agent. CASE PRESENTATION: A 26-year-old female with a history of mild intermittent asthma presented to the emergency department (ED) with acute respiratory distress. The patient reported mild productive cough over the preceding week. Earlier in the day, the patient had consumed the extract of Calendula officinalis, an herbal supplement, for the first time in an effort to alleviate chest soreness. About 30 minutes following ingestion, she developed progressive dyspnea and confusion. At presentation, the patient exhibited disorientation with visual hallucinations. She was hypoxic, with associated tachycardia (147 beats per minute), tachypnea (26 breaths per minute), and hypertension (193/100 mm Hg). She had diffuse expiratory wheezing. Arterial blood gas (ABG) on supplemental oxygen via nasal cannula demonstrated severe respiratory acidosis (pH: 6.9, pCO2: 123, pO2: 136), and she had leukocytosis (27.8 /µl). Chest radiography was unremarkable. She was intubated, and mechanical ventilation was initiated. Epinephrine, methylprednisolone, diphenhydramine, and albuterol were administered, given suspicion for an allergic etiology. A diagnosis of status asthmaticus was made, and she was started on methylprednisolone, inhaled bronchodilators, and empiric antibiotics. Her clinical course was complicated by laryngeal edema which made extubation challenging, but she improved and was successfully extubated. A discussion regarding the risks of unpredictable adverse effects of herbal supplements followed, and the patient was discharged with instructions to avoid similar supplements in the future. DISCUSSION: Calendula is a genus of plants which have been proposed to possess anti-inflammatory, anti-fungal, antipyretic, antispasmodic, anticancer, and other pharmacologic properties, prompting its use as oral tinctures, creams, and lotions in traditional medicine. C. officinalis has been demonstrated to have immunomodulatory properties, such as lymphocyte proliferation and granulocyte stimulation. Considerable evidence has illustrated the role of lymphocytes in modulating airway inflammation, and therefore may have played a role in the causation of the asthma exacerbation in this patient. There is scant documentation of any significant adverse reactions to this plant; to our knowledge, this is the first documented report of an asthma exacerbation triggered by Calendula. CONCLUSIONS: Healthcare providers should advise patients to exercise caution when using Calendula or other herbal remedies with unclear adverse reaction profiles. Reference #1: Arora D, Rani A, Sharma A. A review on phytochemistry and ethnopharmacological aspects of genus Calendula. Pharmacogn Rev. 2013;7(14):179–187. doi:10.4103/0973-7847.120520 Reference #2: Jiménez-Medina E, Garcia-Lora A, Paco L, Algarra I, Collado A, Garrido F. A new extract of the plant Calendula officinalis produces a dual in vitro effect: cytotoxic anti-tumor activity and lymphocyte activation. BMC Cancer. 2006;6:119. Published 2006 May 5. doi:10.1186/1471-2407-6-119 Reference #3: Cruceriu D, Balacescu O, Rakosy E. Calendula officinalis: Potential Roles in Cancer Treatment and Palliative Care. Integr Cancer Ther. 2018;17(4):1068–1078. doi:10.1177/1534735418803766 DISCLOSURES: No relevant relationships by Dan Kazmierski, source=Web Response No relevant relationships by Pius Ochieng, source=Web Response No relevant relationships by NISHANT SHARMA, source=Web Response No relevant relationships by Yichen Wang, source=Web Response