Hrev_master [page 42] [Emergency Care Journal 2025; 21:13421] Emergency Care Journal 2025 volume 21:13421 Abstract Paracetamol, also known as acetaminophen, is a widely used non-opioid analgesic and antipyretic agent. As an easily accessible Over-The-Counter (OTC) medication, the risk of exceeding the maximum daily dosage and resulting in an overdose is significant. Here, we present a case of paracetamol overdose of a 24-year-old male who consumed 15 tablets (9.75 g) of paracetamol given as OTC to relieve his chest pain. The patient was treated with N- acetylcysteine (NAC) and managed symptomatically. This case involves a paracetamol overdose resulting from the patient’s inad- equate comprehension of the term Si Opus Sit (SOS), which trans- lates to “as needed”. This case highlights the importance of patient counseling in the rational use of drugs. Introduction The Latin expression “Si Opus Sit” (SOS) means “as needed”. It is frequently employed in medical settings, especially when writ- ing prescriptions. If patients come across the acronym SOS on a prescription, it means that they should take the drug as needed rather than on a set schedule. When patients need acute symptom alleviation, they should use these medications. Patients’ under- standing regarding SOS is still questionable; they fail to understand what “as needed” means. SOS medications are primarily pre- scribed as over-the-counter (OTC) drugs, including analgesics, antipyretics, antacids, and proton pump inhibitors, among others. While taking medicines as SOS, factors such as the severity of the symptoms, dose, and maximum daily dose are often not considered by the patient. Paracetamol, as an easily accessible OTC, has more tendency to be overused.1 Case Report A 24-year-old male patient was brought to the emergency department of a tertiary care hospital in Bengaluru, Karnataka, India, with complaints of abdominal pain and vomiting and a his- tory of consuming 15 tablets of paracetamol 650 mg (DOLO-650), a total of 9.75 g. The patient had no significant history of previous medical conditions or medications, and he weighed 73 kg. The patient is an Industrial Training Institute (ITI) graduate working in a private company; he also is a part-time auto driver. The patient is a non-alcoholic, non-smoker with no history of any substance abuse. The patient had complaints of gastritis associated with chest pain (3-4 days a week); upon consultation with his physician, he got an echocardiogram and electrocardiogram (ECG) done, and no abnormality was detected. He was prescribed a proton pump inhibitor (omeprazole 20 mg). The patient visited the community pharmacy to buy his pre- scribed medicine. He asked the pharmacist to lend him medicine to relieve chest pain. He was prescribed omeprazole 20 mg and paracetamol 650 mg (OTC) for pain relief and instructed to take it as needed when he experienced pain. He experienced symptoms of heartburn and chest pain in the night, and he consumed omeprazole before his meal and paraceta- mol (650 mg) after meal. Despite being on medication, the pain persisted, prompting the patient to take 15 additional tablets over a period of 10 hours as instructed by the community pharmacist to “take medication as needed”. The patient started to have multiple episodes of vomiting and Correspondence:Shreya Nagraj, Institute of Pharmacy, PES University – EC campus, Konappana Agrahara, Electronic City, Bengaluru 560100, Karnataka, India. E-mail: shreyanagraj2001@gmail.com Key words: si opus sit (SOS); over the counter (OTC); paracetamol overuse; N-acetylcysteine. Contributions: SN, AKNS, MS, writing – review & editing; PK, treatment and patient care. Conflict of interest: the authors have no conflict of interest to declare. Ethics approval and consent to participate: no ethical committee approval was required for this case report by the Department because this article does not contain any studies involving human participants or animals. Informed consent was obtained from the patient included in this study. Consent for publication: the patient has been informed about the publication and assured that his identity will not be disclosed; the information will only be used for scientific and research purposes. Acknowledgments: the authors would like to thank PES University for its constant support. Received: 24 November 2024. Accepted: 17 February 2025. Early view: 9 April 2025. This work is licensed under a Creative Commons Attribution 4.0 License (by-nc 4.0). ©Copyright: the Author(s), 2025 Licensee PAGEPress, Italy Emergency Care Journal 2025; 21:13421 doi:10.4081/ecj.2025.13421 Publisher's note: all claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher. SOS: a silent threat. A case report on paracetamol overdose Shreya Nagraj,1 Akshay Kumar N S,1 Manjari Sharma,2 Praveen Kumar3 1Doctor of Pharmacy, Institute of Pharmacy, PES University, Bengaluru, Karnataka; 2Assistant Professor, Department of Pharmacy Practice, Institute of Pharmacy, PES University, Bengaluru, Karnataka; 3Assistant Professor, Department of Emergency Medicine, PESUIMSR, Bengaluru, Karnataka, India severe abdominal pain. He was immediately rushed to the emer- gency room by his guardian. His vitals showed blood pressure (BP) of 130/80 mmHg, pulse rate of 82 beats per minute, and SpO2 of 98% on room air. Systemic evaluation reveals the presence of CVS S1 and S2, with bilateral air entry confirmed and a soft abdomen exhibiting a positive Blumberg’s sign. No abnormalities were detected in the CNS and laboratory values (Table 1). Based on his history, he was started on N-acetylcysteine IV (9 g in 5% dextrose 500 mL) and ondansetron IV (4 mg). After stabi- lizing the patient with initial management, a psychological evalua- tion was conducted, revealing no evidence of any illness. The patient’s guardian was asked about behavioral changes, and the evaluation concluded that there was no psychiatric illness or abnor- mality, confirming it was not a case of suicide. Symptomatic management was done on subsequent days with IV N-acetylcysteine (6 g in 5% dextrose 500 mL), ondansetron 4 mg, pantoprazole 40 mg, hyoscine butylbromide 10 mg, diclofenac 75 mg, N-acetylcysteine 600 mg, tab vitamin C. He was stabilized with medication and monitored closely and eventually responded to the medication. Discussion Easy accessibility to OTC medications like paracetamol can lead to unintentional overuse.2 Paracetamol poisoning is the most frequent reason for liver transplantation in the United States, and the second most prevalent cause worldwide is acetaminophen poi- soning. In the US, it is responsible for 500 fatalities, 2600 hospital admissions, and 56,000 emergency room (ER) visits annually.3-5 Overdoses that are unintentional account for half of these cases. Community pharmacists play a vital role in providing complete education regarding the safe use of such OTC medications. Patients should also be educated regarding approved indications and maximum daily dose alongside potential risks of misuse or overdose. The term “as needed/SOS” indicates that a medication should be taken “when required”, based on symptoms or specific situations. Patients often misunderstand this instruction and are unaware of the potential risks associated with overdose. In this case, the overdose occurred because the patient misunderstood the “as needed” concept. He took paracetamol whenever he experi- enced pain without considering the maximum daily dose or time intervals. He was also prescribed a proton pump inhibitor (PPI) for gastritis symptoms. The psychiatric evaluation in this case suggest- ed that the overdose was not intentional (not a suicide attempt). This highlights the important role of pharmacists in providing patient education regarding medication use, especially for OTC drugs like paracetamol. In order to ensure the safe and efficient use of OTC medica- tions, community pharmacists play an essential role. These are some important suggestions:6,7 i) appropriate selection: based on medical history and symptoms, pharmacists advise patients on the best over-the-counter medication: they ensure that the selected drug is appropriate and does not interact with any prescription medications the patient is currently taking; ii) label reading: it’s critical to carefully read the labels of Over-The-Counter (OTC) medications; iii) preventing interactions: pharmacists provide guidance on potential drug interactions, especially when patients are taking multiple medications; they can also explain the active ingredients, dosage instructions, and any warnings or contraindica- tions; iv) dose and administration: appropriate dose and adminis- tration are essential; patients should be able to recognize and avoid hazardous combinations and should be informed of how to take medications appropriately, including when to take them and whether to take them with food; v) monitoring side effects: patients need to be informed about any possible adverse effects; pharma- cists can advise people on when to seek medical assistance and what symptoms to look out for. Conclusions This patient’s case highlights the importance of counseling, vigilant monitoring, and prompt intervention in drug overdose sit- uations. It demonstrates the need for improved patient understand- ing of medication guidelines to prevent drug-related problems. Additionally, the case emphasizes the necessity of clear communi- cation with patients regarding medication instructions. The patient, along with the caretaker, was educated in the hos- pital on the use of medication. Basic OTC medications, including their indications, maximum daily dosages, dosing intervals, and other medication-related information, were provided. The patient was then referred to the general medicine department for further evaluation and management of gastritis. References 1. Benlamkaddem S, Iken I, Houari N, et al. Paracetamol self- poisoning: when oral N-acetylcysteine saves life? A case report. Pan Afr Med J 2018;29:83. 2. Shiffman S, Battista DR, Kelly JP, et al. Prevalence of exceed- ing maximum daily dose of paracetamol and seasonal varia- tions in cold-flu season. Br J Clin Pharmacol 2018;84:1250-7. 3. Caparrotta TM, Antoine DJ, Dear JW. Are some people at increased risk of paracetamol-induced liver injury? A critical review of the literature. Eur J Clin Pharmacol 2018;74:147-60. Case Report Table 1. Laboratory tests (on admission). Lab parameters Value Hb 15.3 g/dL RBC 4.84 M cells/mm3 WBC 12.6 K cells/mm3 Platelet count 3.33 Lak cells/mm3 PT time 14.2 seconds Sr. Creatinine 0.89 mg/dL Blood urea 18 mg/dL Sr. Sodium 139 mEq/L Sr. Chloride 105 mEq/L Sr. Potassium 4.2 mEq/L Total bilirubin 1.5 mg/dL Conjugated Bilirubin 0.5 mg/dL Unconjugated Bilirubin 1.0 mg/dL AST 28 U ALT 24 U Sr. Albumin 4.3 g/dL Sr. Protein 7.6 mg/dL A/G ratio 1.30 ALT, alanine aminotransferase; AST, aspartate aminotransferase; PT, prothrombin time. [Emergency Care Journal 2025; 21:13421] [page 43] 4. Pharmaceutical Society of Australia. Dispensing practice guidelines. Available from: https://www.psa.org.au/wp-con- tent/uploads/2019/06/5574-PSA-Dispensing-Practice-guide- lines_FINAL.pdf 5. Chiew AL, Domingo G, Buckley NA, et al. Hepatotoxicity in a child following an accidental overdose of liquid paracetamol. Clin Toxicol (Phila) 2020;58:1063-6. 6. Penna A, Buchanan N. Paracetamol poisoning in children and hepatotoxicity. Br J Clin Pharmacol 1991;32:143-9. 7. Terrie YC, BSPharm, RPh. Proper selection of OTC products: the role of the pharmacist. Pharm Times 2007. Available from: https://www.pharmacytimes.com/view/otc_2007-06_4794 Case Report [page 44] [Emergency Care Journal 2025; 21:13421]