Current Drug Safety - Volume 19, Issue 2, 2024

Introduction: Mercaptopurine, a thiopurine, is used in various disorders of immune regulation, such as autoimmune hepatitis. Thiopurine metabolism is complex with risk for overdosing, especially when metabolism is impaired by liver dysfunction. Hepatotoxicity may be due to mercaptopurine overdose and is often reversible after prompt cessation of the drug.Case Presentation: Treatment of thiopurine toxicity is mainly supportive and literature on enhanced elimination by renal replacement therapy is ambiguous.Conclusion: In this case of thiopurine toxicity, a patient with autoimmune hepatitis presents with abdominal pain, nausea, vomiting, and diarrhea. We show in this case report that renal replacement therapy had no effect on total body clearance of mercaptopurine.

Introduction: Beta-blockers involve a group of drugs widely used nowadays. Propranolol was the first beta-blocker available in the market. It is the most prescribed first-generation betablocker and is commonly used. Beta-blocker allergy is extremely unusual. Only an isolated case of an urticaria reaction to propranolol has been published in 1975.Case Presentation: We present a 44-year-old man. In 2016, he was treated with a daily dose of 5 mg of propranolol prescribed for a diagnosis of essential tremor. On the third day of medical treatment, he experienced an episode of generalized urticaria directly related to the administration of propranolol. He continued with his habitual treatment and he had no other urticaria episodes. A drug provocation test was carried out with gradually increasing doses of the culprit drug. Thirty minutes after a total cumulative dose of 5 mg, the patient had several hives on the chest, abdominal region and arms. Two weeks later, a new drug provocation test was performed to bisoprolol as an alternative beta-blocker, with good tolerance.Conclusion: We describe a new case of urticaria secondary to propranolol, presenting as an immediate hypersensitivity reaction. Bisoprolol has been succesfully proved to be a safe option. Bisoprolol is a second-generation beta-blocker, it is available and commercialized worldwide, which makes it a good alternative.

Introduction: The Coronavirus Disease 2019 (COVID-19) pandemic led to the fast development of vaccines, which is considered a medical advance in healthcare. With the extensive vaccination campaign performed worldwide, many adverse events following immunization (AEFI) were reported. Most of them were flu-like symptoms, mild and self-limiting. However, serious adverse events, such as dermatomyositis (DM), an idiopathic autoimmune connective tissue disease, have also been reported.Case Presentation: In this report, we describe a case of skin erythema, edema, and diffuse myalgia attributed at first to Pfizer BioNTeh, COVID-19 vaccination, given the temporal relationship and the absence of significant medical history. The causality assessment score was I1B2. However, after completing the etiological assessment, an invasive breast carcinoma was identified, and we retained the diagnosis of paraneoplastic DM.Conclusion: This study underlines the importance of completing the etiological assessment before attributing any adverse reaction to vaccination to maintain optimal patient care.

Background: Osimertinib is a third-generation Tyrosine Kinase inhibitor, mainly used in non-small cell lung cancer with EGFR mutation. Its efficacy and safety have been confirmed by clinical practice. Toxic epidermolysis necrotizing disease (TEN) is a severe drug eruption that is rare in clinics and has a high mortality rate. Toxic epidermal necrotic drug rash caused by Osimeritinib is even rarer.Objective: To investigate the rare side effects of Osimertinib through a case of toxic Epidermal necrosis.Case Presentation: A 63-year-old female patient was diagnosed with lung adenocarcinoma with brain metastases, and genetic testing revealed an EGFR21 exon mutation. The disease progressed 24 days after the administration of gefitinib, then the patient switched to Osimertinib (80 mg QD) and, resulting in keratitis and secondary systemic toxic epidermolysis necrotizing disease (TEN). Finally, the patient died.Conclusion: Although the clinical use of osimertinib is becoming widespread, the side effects may not be fully understood. Clinicians should pay more attention to the occurrence of the side reaction and deal with it in time.

Introduction: Spasticity is a common sequelae of stroke, and often these patients receive anti-spastic drugs such as baclofen or tizanidine. Stroke patients have multiple co-morbidities such as hypertension, diabetes, and seizure. Tizanidine is an α2 and imidazole receptor agonist at a spinal and supraspinal level resulting in reduced central sympathetic outflow and causing hypotension rarely, especially in those receiving beta-blockers or angiotensin-converting enzyme inhibitors.Case Presentation: We report a 56-year-old hypertensive male presenting with altered sensorium who had recurrent intracerebral hemorrhage with left spastic hemiplegia and focal seizures. He was on amlodipine, atenolol, telmisartan and oxcarbazepine. After 3 doses of tizanidine 2mg, his blood pressure dropped from 140/90 to 80/40 mmHg and pulse from 82 bpm to 44 bpm. His blood counts, serum chemistry, procalcitonin, and Trop I were normal. ECG revealed sinus bradycardia. After 8 hours of withdrawing tizanidine, his blood pressure became 110/70 mmHg, and on the next day, it became 140/82 mmHg. His attendants were taught physiotherapy to minimize spasticity.Conclusion: This patient highlights the need for close monitoring of patients receiving tizanidine co-medication with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. These drugs have a synergistic effect on reducing the renin-angiotensin-aldosterone system, thereby hypotension and bradycardia.