A commonly used painkiller has been found to be effective against treating the acute pain of shingles, an illness that often causes severe pain along with a rash.
The painkiller oxycodone can help in treating acute pain of shingles, which is caused by reactivation of the varicella zoster virus, a bug that causes chicken pox.
Only those having chicken pox are vulnerable to shingles.
Older adults aged 85 have 50pct increased likelihood of getting shingles.
"Oftentimes patients are told that the rash will heal in two or three weeks anyway, and the pain will go away, so they're not given something for the pain unless it's excruciating," said Dr Robert Dworkin, the University of Rochester Medical Centre pain expert, who led the study.
"But moderate pain can stop people from working, or enjoying their hobbies, and it can also make some people depressed or anxious. So there's good reason to treat all pain from the infection," he added.
In the study involving 87 shingles patients, the team studied the effectiveness of painkillers oxycodone and gabapentin, which both effectively treat pain associated with nerve damage. Patients, whose average age was 66, had moderate to severe pain.
The participants were divided into three groups and received oxycodone, gabapentin, or placebo.
The team found that oxycodone was quite effective. Patients taking the medication, which is sold as Oxycontin, were more than twice as likely to experience a meaningful reduction in their pain - at least a 30-percent decrease.
The study has been published in journal Pain.