We all know the warning signs – bloodshot eyes, coffee cravings and irritability – that tell us we need more sleep.

But what if it’s something more?

With hectic jobs, a barrage of emails and text messages and the pressures of family and friends, it’s easy to brush off perpetual tiredness.

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However, there’s a point at which sleepiness crosses over into the realm of exhaustion, suggesting you might need to seek medical advice or make serious lifestyle changes.

For some, perpetual fatigue can be the sign of something more serious, like sleep apnoea, chronic fatigue, narcolepsy or hormonal issues.

“About 30 per cent of the community are sleepy on a daily basis from a lack of sleep,” says Professor David Hillman, president of the Sleep Health Foundation.

“Just under half of them have sleep disorders like sleep apnoea. These people are sleepy despite reasonable sleep.”

Here’s how to tell if you need more than just a little shuteye.

You look bad

A study participant when well rested (left) and when sleep deprived.

We’re not just talking a bad hair day. A 2010 study from the British Medical Journal found that people who were excessively under slept were perceived as less attractive and less healthy than when they were well rested.

“If you’re excessively tired you tend to have a haggard appearance,” Professor Hillman says. “The kind of thing your mum notices straight away.”

Your needs have changed

We all know your sleep requirements change depending on your age, but if you’ve happily been surviving on seven hours sleep and it’s no longer enough, something’s not right.

“If your sleep requirement is steadily increasing over the years – if eight hours is not enough anymore – there’s something wrong,” Professor Hillman says.

“People with sleep disorders are tired despite reasonable sleep.”

Everything is annoying and hard

Two of the most common symptoms of being chronically under slept are slow reaction times and high irritability.

“The main thing is if you’re not sharp anymore and you’re more irritated and not handling relationships,” Professor Hillman says.

Snapping at your spouse is one thing, but constant fighting and irrational anger may indicate you need to take a look at your sleep patterns.

Holidays are life-changing

Sleep disorders can often be a product of your environment. Removing factors like screen time, sugary foods, stress or shift work, can prove to be a huge wake-up call.

“Sometimes the history of these things is so long that people have lost their calibrations of what’s normal,” Professor Hillman says.

“What they do know is that holidays make them feel fantastic.” 

You’re eating strangely

Aside from the obvious main offender – caffeine – there’s a connection between your eating and sleeping habits.

Constantly snacking could be an attempt to keep yourself awake.

“Shift workers pick at food and are generally overweight and that’s because sleep disruption feeds your hunger hormones and prevents you from having regular meals,” Professor Hillman says.

“When people are tired they tend to eat as an energy boost when they should be sleeping.”

If you’re snacking constantly without any real hunger, warning bells should be going off. 

Nothing is working

Perhaps the most frustrating and telling sign that you may be suffering from exhaustion or a long-term sleep condition is when nothing can help relieve that sense of tiredness.

“Some people have really good habits but are still sleepy,” Professor Hillman says.

“If you’ve already tried lifestyle changes and the problems persist, it’s time to seek professional help.”

What to do:

1. Seek advice from a doctor: Your first stop should be a healthcare professional who can talk you through your sleep patterns and any health problems you may have.

2. Make lifestyle changes: Quitting smoking, exercising more, eating less before bed and removing screens from your room can all assist in getting your sleeping rhythms back to normal.

3. Quit the sleeping pills: “Sleeping tablets have a very small role in all of this,” Professor Hillman says. Speak to your doctor to establish whether your medication could be having some unwanted side effects.