Period Pain Relief Underwear | Heat-Patch Pocket for Cramps

Regular price $32.00
  • Leak-proof period underwear with a built-in pocket for targeted heat relief when you need it most.

Size: Teen 12-14 (Adult 8-10)
Choose how many you need: 1 Pair

* 2–3 pairs can help you feel supported through painful days and nights.

Why you'll love it

For the days cramps take over.

A discreet built-in pocket holds a heat patch gently against her lower tummy, helping ease period cramps without bulky layers. The soft, supportive fit feels comforting rather than tight, so she can rest, study or move through her day.

A favourite for her most painful period days - warmth, protection and reassurance in one.

Best for
  • Period cramps and painful cycles
  • Endometriosis-related discomfort
  • Postpartum recovery and bleeding
  • Lower stomach pain and soreness
  • Days when you want comfort, warmth, and protection together
How the undies work
  • Soft inner layer sits comfortably against the skin
  • Absorbent core helps lock in fluid
  • Leak-resistant layer helps protect clothing
  • Built-in front pocket holds a heat patch securely over the lower stomach
  • Breathable outer fabric helps keep you feeling comfortable

No belts. No shifting heat packs. No extra layers to manage.

Fabric & care

Fabric

  • Outer: Soft cotton blend with stretch
  • Gusset: Absorbent and leak-resistant multi-layer system

Care

  • Rinse after wear
  • Cold machine wash
  • Line dry
  • Avoid fabric softener and tumble drying
Good to know
  • Designed to be worn on its own
  • Heat patches can also be used separately on the back or hips
  • Suitable for teens and adults
  • Reusable and easy to care for
  • Many people choose 2–3 pairs so they feel prepared for painful days across their cycle
Promotion banner

Sizes for tweens & teens

From size 8 up to 6XL

Free shipping over $70*

Straightforward delivery, no surprises at checkout.

Promotion banner

60-Day money Back

Changed your mind? Unworn items can be returned within 60 days.

Aussie support, when you need it

Have a question? Our team is here to help.

Loved by hundreds of customers

WHAT OTHER WOMEN ARE SAYING

Image
5.0
Katie Verified Customer
Love having the post-partum pack at the ready for those unexpected moments.. especially the pantz wipes. The undies are super comfortable.
Period Pain Relief Underwear with Heat Patch Pocket - Fanzy Pantz
5.0
Rosanna Verified Customer
I wore these during postpartum recovery and loved the gentle warmth and coverage. So much easier than juggling pads and heat packs.
Image
5.0
Jess Verified Customer
I deal with bad cramps and this is the first thing that’s made period days feel manageable without lying on the couch all day.
How to Care for

Your Fanzy Pantz Period Underwear

Need Help?

Can’t find what you’re looking for or need personalised advice? Our team is here to help with sizing, absorbency, orders, or anything else you’re unsure about.

Contact Us

How does the heat patch pocket help with period pain?

Our discreet heat patch pocket lets you target crampy, achy spots with soothing warmth, much like a cosy hug for your uterus. Heat boosts blood flow, relaxes muscles, and helps ease those stubborn cramps so you can stay comfy and confident.

How much flow can this pain relief underwear hold?

These pain relief period underwear hold up to 4 tampons’ worth (~20 mL). That’s serious protection for moderate to heavy days, including postpartum and endo flare-ups.

Are these pain relief period underwear gentle on sensitive or postpartum skin?

Yes! Seamless, soft, and made from OEKO-TEX®, GOTS, and GRS-certified materials, it’s toxin-free and super gentle on your most sensitive skin.

Will these undies help with conditions like endometriosis?

Yes, these heat patch period underwear help with conditions like endometriosis. The heat patch and leakproof comfort are perfect for managing endo flare-ups, giving you a discreet way to soothe pain and stay confident throughout your day.

Are these postpartum underwear leakproof?

Yes, these postpartum underwear are leakproof. With our 4-layer leak protection tech, you’re covered head-to-toe. No leaks, no worries, just dry peace of mind for up to 10 hours.

Free shipping over $70


Straightforward delivery, no surprises at checkout.

Promotion banner

60—Day money Back

Changed your mind? Unworn items can be returned within 30 days.

Local support, when you need it

Have a question? Our team is here to help.

Customers praised these as a "game-changer" for period pain relief. The heat patch pocket is called "pure genius" for soothing cramps discreetly. Shoppers love the soft, stretchy, breathable material that's comfortable for all-day wear and bedtime. The pocket proved versatile for storing wipes too. All reviews were 5-star with no negatives reported.

  • The pocket keeps the heat patch snug and right where I need it, and it stays discreet.
  • The pocket for a heat pack is pure genius—perfect for soothing cramps while staying cozy.
  • Super soft, stretchy, and breathable. They feel like a second skin and keep me comfortable all day.
  • 5 stars: 34 (100%)
  • 4 stars: 0 (0%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
Some of the reviews shown are from related products the merchant grouped with this one.
S
Shae E.

Heats up quickly and stays warm! Perfect for on-the-go relief. Super convenient and easy to use. Would definitely repurchase.

L
Louise P.
On the go instant heat packs

I find these extremely helpful when you have those pesky unexpected cramps. It’s great to have them on hand and gives me such relief. I keep them in my car, gym bag and even my work locker as you just never know when you’ll need them ☺️

K
Kylie
Life-Changing for Period Cramps!

This heat patch has seriously changed my life. I used to dread my periods because the cramps were so intense, and going to the gym felt impossible. Now, if I wake up with cramps, I just slip on my high seamfree period undies, stick a heat patch on, and pull on my leggings – no one can even tell! I can finally get through my day (and my workout!) inn comfort. This has made such a difference in my routine, and I actually feel ready to tackle the day. Can’t recommend it enough!

E
Emma B.

the best!! so comfortable & keeps me covered during that time of the month. would highly recommend!!

E
Emma B.

absolutely love these! easy to use & stays warm for sooo long!!

T
Tarinya V.

Got them for my daughter in law and she loved them

A
Amanda A.

Amazing heat patches! My daughter and use them every month… they fit perfectly in your bag and nobody can notice you put them on them!

H
Holly P.

Great product. Works really well.

M
Melisa

super comfy and love the heat pouch! perfect for those days where the cramps are just a bit too much! Love them nd totally recommend! 👌 They also wash really well.

N
Nicole H.

My daughter and I love these! Highly recommend 👌

L
Leeann W.
Great heat packs

Great product. Easy to use and they stay in place. Provide heat for a long period. Thanks Amanda!

L
Leeann W.
Great heat packs

Great product. Easy to use and they stay in place. Provide heat for a long period. Thanks Amanda!

L
Leeann W.
Great heat packs

Great product. Easy to use and they stay in place. Provide heat for a long period. Thanks Amanda!

Z
Zara E.
Wow

These are absolutely life changing. Super easy to put on and heat instantly. Perfect for when you are on a night out or simply at the shops and can stick it on for instant relief! Highly recommend.

Z
Zara E.
Wow

These are absolutely life changing. Super easy to put on and heat instantly. Perfect for when you are on a night out or simply at the shops and can stick it on for instant relief! Highly recommend.

J
Jasmin S.
So comfortable

These period pain relief undies are an absolute game-changer! The pocket for a heat pack is pure genius—perfect for soothing cramps while staying cozy. They’re so comfy, especially for bedtime, and make that time of the month so much more manageable. Love them!

Z
Zara E.
Wow

These are absolutely life changing. Super easy to put on and heat instantly. Perfect for when you are on a night out or simply at the shops and can stick it on for instant relief! Highly recommend.

J
Jasmin S.
So comfortable

These period pain relief undies are an absolute game-changer! The pocket for a heat pack is pure genius—perfect for soothing cramps while staying cozy. They’re so comfy, especially for bedtime, and make that time of the month so much more manageable. Love them!

A
Amanda A.
Good fit and the pocket is great

I used these undies when I travelled to Bali. I used the pocket for a couple of different things, 1 for the heat patch when I needed it but the other was for my wipes. So fricking handy. I had 1 hand wipe, 1 intimate wipe in there and felt so fresh the whole time.

A
Amanda A.
Warmth That Makes a Difference

The warmth from these patches is just right—not too hot, but enough to feel soothing and relaxing. They’re lightweight and don’t feel bulky under clothes, which is a huge plus. Whether I’m running around doing jobs or binge-watching my favorite shows, these patches make those tricky days feel so much

A
Amanda A.
Warmth That Makes a Difference

The warmth from these patches is just right—not too hot, but enough to feel soothing and relaxing. They’re lightweight and don’t feel bulky under clothes, which is a huge plus. Whether I’m running around doing jobs or binge-watching my favorite shows, these patches make those tricky days feel so much

A
Amanda A.
Warmth That Makes a Difference

The warmth from these patches is just right—not too hot, but enough to feel soothing and relaxing. They’re lightweight and don’t feel bulky under clothes, which is a huge plus. Whether I’m running around doing jobs or binge-watching my favorite shows, these patches make those tricky days feel so much

E
Ellie A.
Cozy Relief Whenever You Need It

These heat patches are a lifesaver for those tougher period days. They’re super easy to use, stick right where you need them, and stay warm for hours. I’ve used them at work, while traveling, and even just lounging at home. They’re discreet, effective, and honestly make everything feel a little more manageable.

E
Ellie A.
Cozy Relief Whenever You Need It

These heat patches are a lifesaver for those tougher period days. They’re super easy to use, stick right where you need them, and stay warm for hours. I’ve used them at work, while traveling, and even just lounging at home. They’re discreet, effective, and honestly make everything feel a little more manageable.

E
Ellie A.
Cozy Relief Whenever You Need It

These heat patches are a lifesaver for those tougher period days. They’re super easy to use, stick right where you need them, and stay warm for hours. I’ve used them at work, while traveling, and even just lounging at home. They’re discreet, effective, and honestly make everything feel a little more manageable.

E
Ellie A.
A Hug for Your Cramps!

These are everything when you’ve got cramps but still want to make that weekend getaway happen. The heat pocket is genius—it’s like carrying a little piece of home comfort on the road. Plus, they look cute enough to rock under anything. Function and style? Yes, please!

p
phoenix K.
Cramp Relief That Actually Works!

The Fanzy Pantz Heat Patches are a lifesaver on my toughest period days. The warmth is soothing and lasts for hours, making cramps so much more bearable. I love how discreet and easy they are to use—whether I’m at work or just relaxing at home. They’ve become a non-negotiable part of my period care routine!

C
Chloe
These literally have changed my life

For the past 5 years I have had really bad pains from endo. My friend gave me one of her heat patches last week to try out, wow, it made me feel so much better. I got them with the pocket pants and am now feeling so comfy and free. Previously I didn't want to leave the couch on day one and two but now I can. So happy with these patches. FP, can you do a subscription program with these as I am going to need them all the time. I will probably use about 3 per period so if there was an option to get some every 3 months, I would sign up.

C
Chloe
Pockets in undies is pure genius

So I never realised this was a thing until my friend told me about them last weekend. I purchased them on Monday and got them on Tuesday, which was perfect timing because I got my periods on Wednesday. The stars aligned!!! I also got the heat patches, thank goodness. I used both of them on Wednesday and am so happy to say, I got through day 1 without much pain or leaks. Normally I am taking loads of panadols and sneaking off to the microwave to heat up the heat bag to put under my top at work. Definitely recommend these pants for anyone who gets period pains!

S
Sarah
The Pocket is Pure Genius!

Whoever thought of adding a pocket for a heat patch deserves a medal! These period undies have completely transformed how I deal with cramps. The pocket keeps the heat patch snug and right where I need it, and it stays discreet—no one can tell I’m wearing one.

It’s so convenient to just pop in a patch and go about my day without the hassle of holding a heat bag or constantly reheating it. These undies make dealing with period pain so much easier. I’m obsessed—every woman needs a pair!