Aroha Nuku failed a routine drug test last September, after playing for the Cyclones in their Round four match of the Farah Palmer Cup.
The test found traces of methamphetamine and dextroamphetamine.
According to Drug Free Sport NZ, on the night she was tested Ms Nuku declared the use of supplements and hay fever tablets.
However, she later admitted to also taking what she thought was ritalin in powder form during a drive between Palmerston North and Hawera earlier in the week.
She said she had used it to stay awake during the 2.5 hour trip, following a lengthy team meeting.
Ms Nuku was found guilty of having methamphetamine in her system, but the Anti-Doping Tribunal ruled that "its use out-of-competition and in a context to keep awake while driving, could not be considered intentional under the provisions of the NZR's Anti-Doping Rules".
Because of this, Ms Nuku was handed down a two-year suspension.
It's been backdated to begin from the 22 September 2017- the day the drug test was taken.