The 40 foot yacht, with four crew, was on passage from Inverness to Lowestoft when its steering gear failed 20 miles to the east of Eyemouth.
A cargo vessel contacted Aberdeen Coastguard to offer assistance and was requested to stand by.
Eyemouth lifeboat arrived after 50 minutes and its crew passed a tow to the Prologue.
Once the tow was set up, the cargo ship was released by the Coastguard and continued on its passage.
Once under tow, the Prologue reported to the lifeboat that one of its crew had been suffering from severe sea-sickness for the past 48 hours and was very dehydrated.
This message was relayed to the Coastguard who arranged for an ambulance to meet the crew on arrival in harbour.
The crew of the yacht was advised by the lifeboat to monitor the situation and should there be any change in the condition of the casualty, they should contact the lifeboat immediately.
The tow back to Eyemouth took three hours, during which the casualty’s condition remained stable.
Once the Prologue was safely alongside the pier, paramedics assessed the casualty and were content that they did not require hospital treatment. Once no further assistance was required, the lifeboat was stood down and made ready for service again.