Suffolk MP Dr Dan Poulter has left the government to concentrate on his constituency and medical career – with neighbouring MP Ben Gummer taking on his former job.

Dr Poulter, MP for Central Suffolk and North Ipswich, was junior health minister until the general election. It was a post he had held since September 2012.

He said he had been offered the chance to continue in the role by Prime Minister David Cameron on Monday night – but after sleeping on it had decided to stand down and return to work in medicine part time.

Dr Poulter had continued to work part-time as a hospital doctor after being elected in 2010, but since joining the government he had only been able to work in medicine about once a month – fitting it around ministerial and constituency duties.

He said: “I had a conversation with the Prime Minister and after sleeping on it, I decided I really wanted to continue with my medical work.

“It was a difficult decision – and it might have been different if I had been offered a promotion within the department. But I do enjoy medical work and I felt it was not the right time for me to give that up.”

Dr Poulter said that if he stopped practicing altogether it would be very difficult to start again in a few years’ time because of the speed of medical advances.

He now plans to take further specialist training in psychiatry over the summer and will be working part-time in a London hospital while he undertakes that training.

However he emphasised that he would also be able to devote more time to his constituency duties – his main home is in the Framlingham area and he would be able to combine his training in London with his constituency work in the House of Commons.

He said: “This will give me more time to work on my constituency duties than I had as a minister and give me the chance to continue my medical career.

“Eventually I would like to be able to do psychiatric work at hospitals in the east as well as my constituency work.

“It is also important for me that I am able to spend more time with my family.”

Dr Poulter did not rule out returning to government later in his career: “Who knows what will happen further on in my career, but for the next five years I want to continue my medical work alongside my constituency work,” he said.

Mr Gummer is now looking forward to taking on his new role: “It is a very exciting time for the NHS and I feel incredibly privileged to be part of the journey it is now on,” said Mr Gummer.

“I have been so lucky in Ipswich to be surrounded first class clinicians and NHS management and it is something very close to my heart, as everyone in Ipswich knows.

“It is great to be able to take some of what I have learnt and seen and also what people have said to me on the doorstep and do something about it in Whitehall.”