Halsey has revealed she's undergoing more chemotherapy to treat a rare health disorder.

The singer, 30, who has been open about her health struggles in the past, gave fans a new update on Thursday on her battle with lupus and T-cell lymphoproliferative disorder. 

In a TikTok video, she shared: 'I just wanted to give you a speed round of updates. [I] just did another few sessions of chemo.

'[I] had a new port placed. We just put the Back to Badlands show together, and it's going to be unbelievable [and] so amazing. My birthday's in a couple of days. I'm so busy, I haven't even thought about it at all.'

An implanted port - also known as a portacath or subcutaneous port - is a small device inserted under the skin which is kept in place until chemotherapy treatment finishes.

Lymphoproliferative disorders (LPDs) are conditions where the body makes too many abnormal white blood cells, which can sometimes turn into cancers like lymphoma or leukemia. 

Halsey, who uses she/they pronouns, also shared that she's preparing for a new show amid the treatment.

In the comments of her TikTok video, Halsey described how she's continued her daily life while undergoing chemotherapy.

She said: 'I also can't stand for like a week or more! You guys see me between treatments where I have energy. The time flies by when I'm recovering so it doesn't seem like as long, but it's definitely a while.'

Last year, Halsey revealed she was diagnosed with Lupus SLE in 2022, and then a rare T-cell lymphoproliferative disorder, both of which are being 'managed or in remission.'

Halsey shared on Instagram that she had been diagnosed with Ehlers-Danlos syndrome, Sjogre's syndrome, mast cell activation syndrome - known as MCAS - and postural orthostatic tachycardia syndrome, known as POTS.

At the time, she also clapped back at trolls that had labeled the music artist 'unhealthy' and 'too thin .' In response, the star typed, ''U look sick.' BC I AM. LET ME LIVE.'

It came after she had been hospitalised for Anaphylaxis 'a few times' and had seen '100k' doctors in order to find out what was causing her chronic illness.

On her Instagram stories, she also shared to fans and trolls, 'Obviously, my health has changed a lot since I got pregnant and gave birth and I started getting really, really, really sick.'

Chemotherapy ports deliver medicine and can stay in for years 

An implanted port - also known as a portacath or subcutaneous port - is a small device inserted under the skin which is kept in place until chemotherapy treatment finishes.

It attaches to a long thin tube which goes into a vein close to the heart or sometimes in the arm.

Medicine is given using a special needle inserted into the device through the skin, but this is not painful.

The port can be felt under the skin or a small bump seen, but patients can go home with a portacath in place, and it avoids the need to have needles in the arm during each course of treatment.

The device can be left in for weeks, months or even years – and when it is no longer needed, it can be taken out by a doctor or specialist nurse with an anaesthetic. 

'I've been kind of sick pretty much my whole adult life, but it started getting bad,' she added. 'I'm still looking for answers to the root cause of some of these things. They could potentially be another form of autoimmune disease.'

'And I've known I've had autoimmune issues for most of my life, especially having endometriosis. It's kind of been exacerbated since having [my son Ender Ridley Aydin].'

'I'm keeping you guys updated because I know you're seeing the heart monitor and I'm sick all the time and I don't want anybody to be worrying. I'm on a treatment plan right now...,' Halsey continued.

She added an additional message which read: 'I just want to clarify, for the benefit of friends of friends who may have any of the diagnosis I recently shared.'

'I didn't 'just get sick' I've been sick. For a long time. My sicknesses just have their names now. I went to doctors for 8 years. Trying to figure out what was wrong with me.'

'I was called crazy and anxious and lazy amongst other things,' she candidly wrote. 'I changed my entire lifestyle. When I wasn't working I was essentially confined to my home for fear of how I'd feel when I work up each morning.'

She added, 'It took me a long time to get to even having a diagnosis so I'm celebrating!!'

'Don't roll your eyes at your sick friends. They could be fighting a battle that they haven't named yet. Ya know?'

Halsey also suffers from endometriosis, and gave her followers an update earlier this year in March after undoing a procedure.

At the time, she uploaded a photo to social media and explained that she was 'back in diapers' during the recovery process.

In the image, the star wore striped pajamas and showed the waistband of a diaper that she was wearing as well as bandages.

Text was added over the picture which read: 'Back in diapers, but at least they have little bows.' And lower down, the singer additionally wrote, 'Thank you to my queen @drthaisaliabadi for your unparalleled care and brilliance.'

According to Mayo Clinic, endometriosis 'is an often painful disorder in which tissue similar to the tissue that normally lines the inside of your uterus grows outside your uterus' and 'affects the ovaries, fallopian tubes and the tissue lining the pelvis.'

The Bad At Love singer has also previously revealed her ADHD and bipolar disorder diagnosis.

Halsey is engaged to fiancé Avan Jogia and has one child, a son named Ender Ridley Aydin, with her ex-boyfriend, Alev Aydin.