More than 50 cases were reported in the capital city of Kuala Lumpur and the neighbouring Selangor State.
Selangor police said on Wednesday that seven suspects, who are operators and shop workers selling alcohol, were arrested.
Police also seized 1,030 bottles of whisky and 1,767 cans of beer in a series of raids in the state.
An earlier statement by the health ministry said three of those reported unwell are Malaysians, while 48 of them are foreigners from Myanmar, Nepal, Bangladesh and India.
About 19 have died and some are in critical condition, the ministry said.
Most of the victims had shown early signs of methanol poisoning, including stomachaches, nausea, vomiting, headaches and blurred vision with some developing shortness of breath, cramps and sudden unconsciousness.
They had consumed several brands of whiskey and beers purchased from multiple shops on Monday.
Samples of the alcoholic beverage taken during the investigation at the sale premises have been sent to lab analysis of the content, according to the ministry.
It warned that the number of causality is expected to increase with more patients coming in for treatment of methanol poisoning.
The Nepali Ministry of Foreign Affairs also confirmed on Wednesday that six Nepali nationals died and 16 Nepali nationals were injured from alcohol poisoning in the state of Selangor in Malaysia.
The ministry said in a statement that six Nepali nationals, who fell sick after consuming alcohol in Malaysia, died during their treatment at Sungai Buloh Hospital and Kajang Hospital based in Selangor.