Medicosnext
Risk of acute tubulointerstitial nephritis (TIN)
The South African Health Products Regulatory Authority (SAHPRA) has alerted health-care professionals on the risk of acute tubulointerstitial nephritis (TIN) associated with use of Proton Pump Inhibitors (PPIs: pantoprazole, dexlansoprazole, esomeprazole, and rabeprazole). TIN (previously called interstitial nephritis) is characterized by an inflammatory reaction within the tubulointerstitial space of the kidney, and acute TIN can result in acute kidney injury. Symptoms and signs of acute TIN may be nonspecific and are often absent unless symptoms and signs of renal failure develop. Many patients develop polyuria (increased frequency of urination) and nocturia (the need for patients to get up at night on a regular basis to urinate). Health-care professionals are advised that treatment by PPIs must be stopped when TIN is suspected; PPIs are contraindicated in patients who previously experienced TIN while on treatment with PPIs; and patients should be asked to report any alteration in urine volumes or if they suspect that there is blood in their urine while on PPIs.
Reference: Safety Information and Updates, SAHPRA, 30 October 2023 (www.sahpra.org.za)
Mefenamic acid
Potential risk of drug reaction with eosinophilia and systemic symptoms (DRESS)
The Indian Pharmacopoeia Commission (IPC) has announced that its preliminary analysis of the Pharmacovigilance Programme of India (PvPI) database has found a potential risk of drug reaction with eosinophilia and systemic symptoms (DRESS) associated with use of mefenamic acid. Mefenamic acid is a nonsteroidal antiinflammatory drug (NSAID) and is indicated for the treatment of mild to moderate pain, inflammation, fever, and dental pain. It is usually considered the drug of choice in dysmenorrhea and falls in the OTC category. Mefenamic acid with Dicyclomine Hydrochloride is often used for dysmenorrhea. Health-care Professionals, and patients are advised to closely monitor the possibility of DRESS associated with mefenamic acid and to report it if a suspected event occurs.
Reference: Monthly Drug Safety Alert, IPC, 30 November 2023
Fluoroquinolone antibiotics
Risk of suicidal thoughts and behaviour
The MHRA has reminded health-care professionals to be alert to the risk of psychiatric reactions, including depression and psychotic reactions, which may potentially lead to thoughts of suicide or suicide attempts. The MHRA has received a coroner’s report following the death of a patient who died by suicide after being treated with ciprofloxacin. Warnings on the potential for psychiatric adverse drug reactions to occur with ciprofloxacin and other fluoroquinolones are included in the product information. In rare cases, depression or psychosis can progress to suicidal ideation or suicide attempts. If this happens, ciprofloxacin should be discontinued immediately. Health-care professionals are also reminded to advise patients to be alert to these risks.
Reference: Drug Safety Update, MHRA, 26 September 2023
Myasthenia Gravis Advances in Treatments
Myasthenia gravis (MG) is an autoimmune disorder characterized by muscle weakness. Historically, MG had a grim prognosis, often resulting in severe respiratory issues and early death. However, modern treatments have drastically improved the outlook for individuals with MG, enabling many to live longer, healthier lives.
Current Treatments: The first effective treatment for MG emerged in 1934 with the introduction of acetylcholinesterase (AChE) inhibitors. Despite their effectiveness, some patients may need additional therapies. Immunosuppressive drugs, including tacrolimus, azathioprine, prednisone, mycophenolate mofetil, and cyclosporine, are also crucial in managing MG. These medications dampen the immune response, preventing it from attacking the neuromuscular junction. While effective, they can cause significant side effects, requiring close medical supervision. Biologics, a newer class of MG treatments, offer targeted therapy to specific components of the immune system. Examples include rituximab, eculizumab, and efgartigimod, which can provide significant relief with potentially fewer side effects than broader immunosuppressants. For severe MG cases, plasmapheresis and intravenous immunoglobulin (IVIG) are often used. Plasmapheresis filters out harmful antibodies from the blood, while IVIG introduces healthy donor antibodies to mitigate the autoimmune attack. Thymectomy, the surgical removal of the thymus gland, is another long-standing treatment that can lead to significant symptom relief and remission in many patients.
Developing Therapies: Despite the effectiveness of current treatments, a subset of MG patients continues to experience significant symptoms and side effects. Emerging treatments include B-cell depletion therapies, complement inhibitors, and neonatal Fc receptor antagonists. These approaches aim to target the disease more precisely and reduce side effects. Promising drugs in the pipeline include batoclimab, gefurulimab, and nipocalimab, among others. These medications are undergoing clinical trials and could soon provide more effective and targeted treatment options for MG patients. The approval of new drugs and the expiration of patents, such as that of eculizumab in 2027, will likely increase the availability of generic alternatives, making treatments more accessible.
