Allardyce will miss Sunday's game against his former club Bolton, the midweek trip to Fulham and then the clash with Stoke at Ewood Park next weekend as he is having an angioplasty.

Assistant manager Neil McDonald will take charge in his absence.

Allardyce has complained of brief episodes of chest pains in recent weeks and tests have revealed he requires an angioplasty - a procedure that involves inserting a stent to widen a narrowed coronary artery.

The 55-year-old, who spent eight seasons at the Reebok, is expected to return for Rovers' Carling Cup tie against Chelsea on Wednesday week.

"Sam is very disappointed, particularly at missing the Bolton fixture, but his well being is of prime consideration," Blackburn chairman John Williams told the club's official website.

"We all appreciate that Premier League football is a stressful business and prevention is always better than cure."

In Allardyce's absence Rovers will aim to halt their horrendous Premier League away form.

Rovers have lose their past 10 league encounters on the road - shipping a whopping 18 goals in five matches this season - and while Allardyce will be missing on Sunday, he hopes the atmosphere of a Lancashire derby can brew a change.

"For most of my football life I have been on the opposite side both as a player and a manager," said Allardyce, in his 12th month in charge at Ewood Park.

"I know the passion involved in a derby like this and I hope it is a spur for the players to deliver a result.

"Because it's time we changed the away form and time we put points on the board.

"There can't be a better time than going to our old rivals Bolton and doing that."

Controversial Senegal forward El Hadji Diouf was a big hit with Bolton fans but has yet to win over the Rovers faithful.

However, Allardyce suggests people should recognise his worth.

"He kept us up (last season)," Allardyce said.

"The major fact people still haven't quite digested is the huge task we came through last season to stay in the Premier League.

"It was absolutely humongous in terms of an achievement, one of the best things as a manager I have ever done and Dioufy was a part of that.

"In the January transfer window there was only Dioufy and Gael Givet that we brought in and out of the teams in and around the relegation zone at the time we were probably the one which spent the least amount of money.

"Those two players played nearly every week from there on and built a platform to get ourselves out of trouble.

"Yes, he has delivered and he is always the type of player you think there is more to come out of.

"But you tend to miss him and realise how good he is when you haven't got him.

"Ever since he has been here he has contributed an awful lot."