Wanted to post on here to make people aware that despite the low incident rate of 1 in 100 patients having an allergic reaction to the Mirena IUS, it does happen. I had just had one! Here's a quick description of me & my symptoms so people can note what an allergic reaction to Mirena hormonal coil looks like:
I'm 41 and had the Mirena coil fitted about 18 months after my last pregnancy. I've had 2 kids and didn't want any further children. I'm in good health but slightly overweight.
Fitting the coil wasn't painful but I did spot each say for about 6 weeks and have cramps. Then it settled down and seemed ok.
3 months after fitting, I notice I'm very bloated in the tummy area. I put it down to mid life weight gain but was puzzled by it. I then realised I've gained 10lbs in 3 months. I also developed lower backache and my waist is non existent. I look thick around the middle.
At 4 months after insertion my tummy is not just bloated but hard to the touch. It felt like it did when I was about 16 weeks pregnant. Alarmingly, one day I look so bloated in the abdomen and woke up with severe abdominal cramps. It felt like I was in early stage labour. I had been feeling dizzy for about a week and this worsened. I attended A&E as the bloating in my abdomen was so large I looked pregnant,and it was putting pressure on my diaphragm, causing me to wheeze. The patient leaflet said if wheeziness occurs go straight to a Dr as it's a sign of an allergic reaction.
In A&E, they thought I could potentially have gallstones as I had an enlarged gall bladder. But then decided there was swelling in all the abdominal area so an ultrasound ruled that out. I was scanned for ovarian cysts and tested for pregnancy and cancer. Thankfully, it was all clear. I had the IUS removed 48 hours later in a sexual health clinic as no Drs in A&E were trained in removing coils/ all male medics on duty?!!! /they wouldn't refer me to gynaecology at 2am unless it was an obstetric emergency.
After getting the Mirena IUS removed the following symptoms disappeared within about 48 hours: swollen abdomen / uterus went down, swollen hands and feet back to normal, stabbing pain in stomach disappeared, lose back pain gone.
What remained was the dizziness and lethargy.
Then 9 days after the IUS had been removed, I developed an additional stage to the allergic reaction to Mirena. I suddenly broke out in hives from head to toe. I've previously had an allergic reaction with hives due to penicillin and got admitted to hospital with it whilst pregnant. So I was told by NHS 111 to go straight to A&E within the hour. I took some antihistamines within 10.minutes of seeing the hives erupt just in case it would help calm my reaction to it. The Dr in A&E treated me immediately with prednizalone steroids 30mg dose and cetrizine antihistamines and took blood samples for further testing. I was discharged after a few hours of observation and prescribed a 3 day dose of steroids.
I wanted people to be aware this looks like an allergic reaction to Mirena that's happened in two stages. Stage 1 was swelling of the abdomen that escalated from looking puffy to causing wheeziness of the chest within about 3 days. Stage 2 was around 9 days after the Mirena coil was removed and was hives suddenly appearing within 10 minutes, forming a swollen red rash all over the body within 3 hours. This requires steroid treatment in A&E.
Please be wary of the Mirena coil and make sure you tell medics if you suspect any symptoms might be linked to it. There seems to be limited awareness of whether it can cause an allergic reaction or not as it's not very well documented. The patient leaflet lists hives and swelling as "uncommon, affects 1 in 100 or 1 in 1000 patients. " but it's still a significant side effect nonetheless.
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