Premier Su Tseng Chang has been diagnosed with temporary facial palsy due to a viral infection triggered by overwork. Su took Monday off. He is planning to curtail his work schedule in the coming days.

As the legislative and presidential elections are heating up, the premier has been busy campaigning for the ruling Democratic Progressive Party (DPP) and for his daughter as well, who is running for legislator.

At a campaign rally for his daughter Saturday, Premier Su Tseng-chang looked a bit odd. The left side of his face was distorted, which is a symptom of temporary facial palsy.

Neurologist Lien Li-ming says facial palsy is caused by a viral infection due to a lack of enough rest.

Dr. Lien says patients with temporary facial palsy often have their mouth tilted to one side due to weak facial muscles.

Dr. Lien says if the central nervous system is under attack, it could be a stroke. A viral infection will affect the peripheral nervous system.

Diabetics and those with a weak immune system who display these symptoms should see a doctor and get enough rest. Patients usually can recover in about a month.