Onset-8mg Inj 4ml is an ondansetron injection used to help control nausea and vomiting when fast relief is needed. The 4ml size is suitable for medical use under professional guidance, making it a practical option for patients who need a trusted pharmacy item from Tasco Supermart with online delivery in Karachi. It is commonly kept in clinics and home pharmacy stocks for prescribed use after surgery, illness, or other causes of vomiting.