Background: In sub-Saharan Africa, rectal diazepam or intramuscular paraldehyde are commonly used as firstline anticonvulsant agents in the emergency treatment of seizures in children. These treatments can be expensive and sometimes toxic. We aimed to assess a drug and delivery system that is potentially more effective, safer, and easier to administer than those presently in use. Methods: We did an open randomised trial in a paediatric emergency department of a tertiary hospital in Malawi. 160 children aged over 2 months with seizures persisting for more than 5 min were randomly assigned to receive either intranasal lorazepam (100 μg/kg, n=80) or intramuscular paraldehyde (0.2 mL/kg, n=80). The primary outcome measure was whether the presenting seizure stopped with one dose of assigned anticonvulsant agent within 10 min of administration. The primary analysis was by intention-to-treat. This study is registered with ClinicalTrials.gov, number NCT00116064. Findings: Intranasal lorazepam stopped convulsions within 10 min in 60 (75%) episodes treated (absolute risk 0.75, 95%CI 0.64-0.84), and intramuscular paraldehyde in 49 (61.3%; absolute risk 0.61, 95%CI 0.49-0.72). No clinically important cardiorespiratory events were seen in either group (95%binomial exact CI 0-4.5%), and all children finished the trial. Interpretation: Intranasal lorazepam is effective, safe, and provides a less invasive alternative to intramuscular paraldehyde in children with protracted convulsions. The ease of use of this drug makes it an attractive and preferable prehospital treatment option. Background: In sub-Saharan Africa, rectal diazepam or intramuscular paraldehyde are commonly used as first line anticonvulsant agents in the emergency treatment of seizures in children. We aimed to assess a drug and delivery system that is potentially more effective, safer, and easier to administer than those presently in use. Methods: We did an open randomized trial in a pediatric emergency department of a tertiary hospital in Malawi. 160 children aged over 2 months with seizures persisting for more than 5 min were randomly assigned to receive either intranasal lorazepam (100 μg / kg, n = 80) or intramuscular paraldehyde (0.2 mL / kg, n = 80) The primary outcome measure was whether the presenting seizure stopped with one dose of assigned anticonvulsant agent within 10 min of administration. The primary analysis was by intention-to-treat. This study is registered with Clinical Trials.gov, number NCT00116064. Findings: Intranasal lorazepam Stop convulsions within 10 min in 60 (75%) episodes treated (absolute risk 0.75, 95% CI 0.64-0.84), and intramuscular paraldehyde in 49 (61.3%; absolute risk 0.61, 95% CI 0.49-0.72). No clinically important Interpretation: Intranasal lorazepam is effective, safe, and provides a less invasive alternative to intramuscular paraldehyde in children with protracted convulsions. The ease of use of this drug makes it an attractive and preferred prehospital treatment option.