Multiple sclerosis (MS) drug wipes out bad memories.Wheeler Cowperthwaite/Flickr

Haunting memories will soon become a part of history as popping a pill will now be enough to forget those unpleasant emotions.

A team of US scientists have found a drug named fingolimod, which is highly effective in eradicating bad memories. Fingolimod, also known as Gilenya is a drug approved for treating progression of a nervous system disease known as multiple sclerosis (MS).

The medicine works by blocking the activities of white blood cells in brain and spinal cord. Researchers found that these drugs were equally effective in stopping activities of histone deacetylase (HDAC), an enzyme that plays a major role in gene expression.

For proving the effect, researchers locked a group of mice in a chamber and gave mild electric shock to them. Though, the rodents showed symptoms of shock and anxiety by remaining still in their cage, they started recovering after taking the medicine.

Mice that received the drug, completely forgot the unpleasant events. The drugs successfully crossed the blood-brain barrier and removed the scary memories from their mind, researchers explained.

The breakthrough discovery is expected to help treat various diseases triggered by painful experiences, including post-traumatic stress disorder (PTSD), eating disorders, phobias and sexual problems, Daily Mail reported.

Post-traumatic stress disorder is a severe anxiety disorder caused by exposure to a traumatic event. PTSD patients relive their traumatic experiences through memories, flashbacks or nightmares and try avoiding anything that reminds them of the trauma. Treating this condition early is crucial as it can lead to poor concentration, hyper vigilance and insomnia.

Previous studies on the topic have provided mixed outcomes. While some chemicals successfully blocked HDAC activity, some left a negative impact on the mind by amplifying the memories, or were toxic, The Australian reported.

"Fingolimod, a Food and Drug Administration approved drug for treatment of multiple sclerosis, has beneficial effects in the central nervous system that are not yet well understood," Dr Sarah Spiegel, from the Virginia Commonwealth University, US, told Daily Mail. "Fingolimod deserves consideration as an adjuvant therapy for post traumatic stress disorder and other anxiety disorders."

However, the discovery is also feared to leave a negative impact on the natural ability of the mind to learn from its previous bad experiences.

The study has been published in the journal Nature Neuroscience.

Eradicating bad memories has been an interesting topic among researchers across the whole globe lately. Last month, a team of researchers from the Beckman Institute, University of Illinois in US found that concentrating on the "contextual elements of a bad memory" can help manage the pain it cause in humans, The Telegraph, UK reported.