RLSP chief Upendra Kushwaha and several other party leaders were injured in a clash with the police on Saturday after they were prevented from marching towards the Raj Bhavan.
The condition of Mr Kushwaha, the former Union Minister of State for Human Resource Development, is all right, although he has been advised rest, the hospital sources said.
Mr Kushwaha's Rashtriya Lok Samta Party (RLSP) had organised a ''Aakrosh march'' on Saturday against the Nitish Kumar government to press for its demand of educational reforms in the state.
The RLSP programme was organised on the occasion of the birth anniversary of late Jagdeo Prasad, the tallest leader of Bihar from the Kushwaha community, considered to be the party's primary support base.
Armed with ''lathis'' (sticks) and raising slogans denouncing the state government for failing to do the needful on the party's charter of demands on educational reforms, the RLSP leaders came to blows with policemen at the Dak Bungalow crossing, about two kilometres from the Governor's residence.
When the agitators tried to force their way past the police cordon, they were quelled with baton charge and water cannons.
Mr Kushwaha, who had received blows on his body, squatted on the roadside along with a number of supporters alleging that they had informed the police about their march.
If we were not supposed to go beyond a certain point, we should have been informed beforehand, a party leader said.
"But the administration did nothing of that sort. It remained indifferent when we began our march and came up with an abrupt order to halt when we reached Dak Bungalow crossing," Mr Kushwaha alleged.
"The police has acted at the behest of the dictatorial government in the state, which wants to crush all dissent," he added.
The former Union minister, who quit the National Democratic Alliance (NDA) in December and joined the Opposition Mahagathbandhan (Grand Alliance) subsequently, felt unwell while venting his ire and was taken to the Patna Medical College and Hospital.
Hospital sources said his condition was fine and had been administered first aid and advised rest.
Meanwhile, the ruling Janata Dal (United), headed by Mr Kumar, criticised the RLSP for "demanding educational reforms while carrying lathis in hands".
"What did Kushwaha do for improving the education system while he was the Union Minister of State for HRD," asked party spokesperson Ajay Alok.
"And why does his party need to carry lathis to demand educational reforms. Do they equate their hooliganism with learning," he said.