Several people had to be sedated at Auckland's Middlemore Hospital over the weekend after pills they believed were ecstasy caused them to become highly aggressive and agitated.

Six people were admitted to the hospital's emergency department the previous week exhibiting similar symptoms.

They are understood to have taken red-coloured pills inscribed with a rocket graphic known as "Red Rockets".

Ecstasy - the street name for methylenedioxymethamphetamine (MDMA) - is normally associated with feelings of energy, euphoria and closeness to others.

Possession of the Class B drug is punishable by up to three months jail, a $500 fine or both.

Those admitted to Middlemore Hospital during the last fortnight have suffered side effects including agitation, aggression and hallucinations and have had to be sedated by hospital staff.

Police were called to one instance in Pukekohe where a young man suffered a powerful psychotic seizure in which he was hallucinating in a semi-conscious state and damaging property.

In another incident in the area, one man fell to the floor of a bar in a violent seizure.

Police say the pills were part of a bigger batch and are concerned more will be circulating amongst the bar and party scene.

While police say they discourage any drug use they particularly urge people not to take the Red Rocket pills.

According to the Drug Foundation, Ecstasy is one of the most commonly used recreational drugs in New Zealand, however, they say it is becoming increasingly difficult to obtain.

They say overdose can often result when pills contain unknown and unexpected substances.

- Auckland Now and Franklin County News