A clash witnessed between business protesters and police on Friday led to a number of pupils from Ndurarua Primary School in Kawangware Estate caught up in the melee.
The students were having their morning classes when police officers engaged the traders in running battles.
The traders were reportedly agitating against a decision by the Nairobi County administration to demolish their kiosks, said to be constructed on footpaths and feeder roads.
Police had difficulty clearing the roads on which the protesters had barricaded, burnt tyres and destroyed posters.
The anti-riot police officers lobbed teargas to disperse the traders.
Some of the canisters are said to have landed in the school causing panic to the students who scampered for safety.
The drenching smoke of teargas from the canisters however affected some of the students who ended up losing consciousness.
In a video, the pupils are seen carried to a police vehicle so as to be rushed to the hospital.
They were then taken to various hospitals around Kawangware estate where they received breathing difficulties treatment.
It was observed that the students who remained in school were in stable condition and did not need direct medical admission at hospitals.
The protest also affected adjacent roads leading to Riruta, Wanye and other parts of Kiambu County.
Police have yet to release a statement to clarify the incident.