BENGALURU: Think twice before using eucalyptus oil or eucalyptus pain balm in case of headache and a runny nose. Inhalation of eucalyptus oil could cause seizures, says a study conducted by Bengaluru’s top neurosurgeons. The study was done at four city hospitals from October 2014 to March 2018, where 55 cases of eucalyptus oil-induced seizures (EOIS) were seen. Researchers say physicians rarely ask about exposure to eucalyptus oil when seeing a patient, who has no history of epilepsy and is faced with the first episode of seizure.In such cases, without understanding the cause of seizures, patients are treated for idiopathic (cause not known) epilepsy and they live with side-effects of the drug and stigma, say doctors. The study was conducted by the neurology departments of St John’s Medical College Hospital, Apollo Hospitals, Sakra World Hospital and Vydehi Institute of Medical Sciences. It was published in international journal Epilepsia Open, and in March, the team presented the study before the American Epilepsy Society. “Sadly, such cases are misdiagnosed as idiopathic seizures and patients are unnecessarily put on epileptic drugs. Epilepsy has stigma attached to it and marriage becomes difficult for many youngsters with EOIS. Besides, anti-epilepsy drugs have side-effects like drowsiness and memory issues. However, such cases do require six months of follow- up,” said Dr Thomas Mathew, professor (HoD), neurology, St Johns’s Medical College and Hospital, who spearheaded the study. Dr Prarthana Hareesh and Dr Meghna Srinivas from St John’s, Dr Vikram Kamath, Dr Rakesh Jadav and Dr Sreekanta Swamy of Apollo Hospitals and Dr R Shiva Kumar of Sakra World Hospital were also part of the study. Dr Thomas recalled a case in which a 45-year-old man came with a burnt face; he had also bitten his tongue. The man who had suffered seizures had apparently inhaled eucalyptus oil while taking steam. In 2016, there was a case of a 26-year-old techie suffering seizures while taking steam using a pain balm that had concentrated eucalyptus oil. In both the cases, there was no history of seizures. “If there is a case of seizure reported in any hospital’s emergency unit, doctors must check if the patient has had seizures earlier too. If there is no such history, then doctors must check if the person tried any kind of inhalation prior to the seizures,” added Dr Thomas. Neurologists across the city confirmed that such cases were seen in other hospitals too. A two-year-old boy, who had no fever, suddenly started having seizures. At the hospital, the boy’s mother told doctors that two drops of eucalyptus oil had been put into his nose as he had cold. The study suggests a multi-centric, multi-national research involving larger number of patients to ascertain the severity of this problem as these oils are used the world over. “We are not saying something is good or bad. But the person must be informed before using eucalyptus oil or balms on the right quantity of usage. The product should mention that it could cause seizures. Our study is hypothesis based; clinical research is yet to be done,” said Dr Rakesh Jadav, consultant neurologist, Apollo Hospitals. Dr Jadav further added that EOIS is not seen among all eucalyptus oil users and that there must be something triggering seizures in some persons compared to the rest. University of Agricultural Sciences faculty, working in the area of forest and environmental sciences, said the study findings came as a shocker for them. “We are hearing such a thing for the first time. We have to go through the study conducted by the doctors,” said a professor. “Eucalyptus-induced seizure is well-known and can be seen in history and medical literature. But we have come to understand more about it now,” said Dr Dr P Sharat Chandra, noted neurologist and former director of Nimhans. A single episode of seizure without any such history and the exposure to eucalyptus oil prior to its occurrence is common in all these cases, he pointed out.