Abdelghani Chaabani, director of health of the central town of Kasserine, told AFP that 30 people from the same district had been rushed to hospital on Saturday evening.
"Samples have been taken and are being analysed to confirm the cause of death," said Dr Chaabani, referring to a "mixture" of alcoholic substances.
Five of the victims later died, while two others remain on life support. Eleven others have since been able to leave hospital, Chaabani said.
Police have launched an investigation into the poisoning.
Such homemade alcoholic drinks are common in poor and isolated districts of Tunisia, being cheaper and more accessible than beer.
Last May, six people died and 33 others fell sick after consuming a methanol derivative in Tunisia's central Kairouan region.
In Kasserine, a farming area bordering Algeria, a fifth of people are without work and a third live in poverty, according to government statistics.
Tunisia's already dire economy has been hit hard by the coronavirus pandemic and stringent measures to rein in the spread of the virus.
The country has registered over 7,000 Covid-19 deaths.
A decade on since the 2011 revolution, many Tunisians are angered at the economic situation, the pitiful state of public services and the inability of the political class to deliver change.
Follow us on , and to stay connected