The TV presenter opened up on Instagram, sharing a picture of herself in a hospital bed with the sheet pulled up to her chin, and another of her sat by her bed in compression socks.
She didn't elaborate about her symptoms, but told fans that she had got herself "into such a pickle".
Sawalha, 57, also urged people to get seen if there was anything they were worrying about.
"The only reason I’m posting these pics is because I want to catch your eye and urge you if you have been worrying about any symptoms you’ve been experiencing to bite the bullet and get yourself seen!" she said.
"Delaying things will only cause more worry.
"I’m not going to lie I’ve been worried sick myself recently but was given the all clear on Monday! I only wish I had dealt with it earlier so I didn’t get myself into such a pickle."
The TV star urged her followers: "Don’t delay make the call. Get seen. You know it makes sense."
Fans wished the star well after she shared what she'd been through.
"So glad everything is OK," one person posted on Instagram.
"Sending you the biggest of hugs beauty... thank God you are OK," said someone else.
Another said: "So happy to hear you are OK Nadia, we can't have you unwell. Sending loads of love and respect for raising awareness."
"Great to hear you’ve got good results my lovely!" said one fan. "And well done for getting this message out there… wise lady."
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