The circuit breaker has been a period of extreme isolation for Mr Daniel Ler. He lives alone, works from home, has few friends to talk to, and now even has reduced access to his psychiatrist, who is not seeing patients face to face until June 1.

The 39-year-old, a freelance programmer, was diagnosed three years ago with manic depression, also known as bipolar disorder.

He is among some people who are finding it increasingly hard to cope with their mental health issues as some psychiatrists close their clinics or limit the number of patients they see daily, and online mental health services are swamped.

The conditions they are being treated for range from minor depression to schizophrenia.

Amid safe distancing measures and having to stay home except for essential errands, Mr Ler found himself withdrawing into his own world and oscillating between sleeping for 16 hours a day and going three to four days without sleep.

"It's like my emotions are on a sharply swinging pendulum: One moment I might be super energised, and all I want to do is run and jump, and talk endlessly - and an hour later I'm lying on the floor crying about nothing in particular," he told The Straits Times.

He messages his psychiatrist, who runs a private practice in the central area, whenever he feels himself going "off the rails", but has not had a proper therapy session in over a month. Prior to the circuit breaker, he met friends and collaborators at work once a week, and worked at cafes so he would not be cooped up at home. "Being able to leave the house... helped me regulate my emotions better. Since that's no longer an option, some negative emotions have definitely got the best of me, and I've been trying to seek help as best as I can," Mr Ler said.

The prolonged isolation some might be experiencing during the circuit breaker might be making more people feel worse for wear. An Ipsos survey conducted from April 24 to May 4, which polled 1,000 Singaporeans and permanent residents over the age of 16, also indicated one in four people here was in "fair or poor mental health" during the circuit breaker.

Ipsos Singapore's director of public affairs Tan Hui-Ching said: "Of those who say that their mental health is good at the moment, it is not to say that it will continue to be good. There are some in this group who also say that their mental health is declining as the days pass."

The World Health Organisation has advised people feeling isolated to stay connected and maintain one's social networks, via telephone, e-mail, social media or videoconferencing. But going online sometimes presents its own problems. Student Annie Loke, 27, who was diagnosed with a paranoid personality disorder two years ago, told ST she ends up on a "Googling spree" when she catches wind of any information on the outbreak on social media or via friends.

"It's only after I start feeling hungry at five in the morning that I realise I've been sitting here for six to seven hours just going down this rabbit hole of digesting endless streams of information that might well be unreliable or worse, false," she said.

Miss Loke, who sees her psychiatrist remotely once a week, said: "My doctor advises me to just log off, but it's just not that easy. There's nothing else to do."

Some patients have also sought out online psychologists for help.

Undergraduate Zijun, who is in his 20s and declined to give his full name, said while he has enough medication for his depression, he realised he needed some help, but was hampered by long waiting lists on online counselling portals. He is now using BetterHelp, an online portal which pairs patients with therapists.

"This is a temporary stopgap measure to prevent my condition from worsening rapidly," he said.

Help is also available at the Institute of Mental Health (IMH), which runs a helpline. It saw a 15 per cent increase in calls last month, compared with January.

It also started offering consultations via phone or video calls to patients last month, said Adjunct Associate Professor Lee Cheng, senior consultant and vice-chairman (clinical) at the IMH Medical Board.

For cases involving high-risk patients with severe conditions, home visits are made while taking the necessary precautions, he said.

"For patients requiring closer follow-up or with less stable conditions, it is important that they keep to their appointments for our doctors to review them," he added.