How to Make Microwave Heat Bags for Pain Relief

Sore muscles, menstrual cramps, postpartum pain, or just a child’s booboo — there are lots of reasons you might want to keep microwavable heating pads on hand. Making your own microwave heat bags is a great way to bring gentle heat or cooling relief to any ache or pain.

This project is a super simple way to give affordable and practical presents as well. 

Years ago, in Kansas City, mind you, a friend gave us a cloth pillow filled with dry feed corn. I thought it was crazy. And then she said, “You know a friend gave me one and I thought she was crazy. But, it’s really amazing how nice it is in the winter.”

How right she was! We had one “corn bag” or microwaveable heat pack to share among the seven of us that first winter. The kids would take turns heating it in the microwave and then slip it under the covers to warm up their beds.

Once they fell asleep, we parents would snatch the corn bag to heat up our own bed. Oh, yes, yes, we did.

In summer time, the boys would store it in the freezer to cool off with! Clever fellows.

Corn Bags Make a Great Gift!

That was the year of our Great Awakening, when we started to pay off all our debts. We had no money to buy gifts, and the only thing the boys wanted on their list were corn bags of their own. They were so sweet about it. They knew we had NO MONEY to buy gifts, so their requests were humble and modest.

Indeed, these are some of the best frugal gifts I’ve ever given.

Microwave Heat Bags are a great gift you can make yourself. They are perfect for Secret Santa gift exchanges since everyone needs a little cool or warm relief from time to time.

Determined to give them something fun — and super thankful that the grandparents were picking up our slack — I bought colorful fabric in the patterns that I knew would please them (Kansas City Chiefs, dinosaurs, Thomas the Tank Engine, and rainforest lizards). After they went to bed, I sewed up a storm, even making little hand size packs to put in their pockets. 

It was a great Christmas, and the boys were thrilled with their gifts.

Since then “corn bags” — even though the current ones are filled with rice — have been a staple in our home for soothing muscle spasms and bring comfort on cold days.

This is an easy, fun gift to make for your kids or for yourself! You just need to be able to sew three straight lines. That’s it!

Uses for Microwave Heat Bags

Though my current microwave heat packs contain rice, my kids still refer to them as “corn bags” and have used them since they were very young. They’ve used them for:

• warm heat pain relief of shoulder pain, neck pain, muscle pain – If you have a chronic pain, these are really nice to have on hand for natural pain relief, a great gift for new moms!
• warming up in cold weather – I’ve made small bags to warm cold hands in winter and we regularly use them to warm cold beds before bedtime.
• cold pad or cool therapy – store them in the freezer so they’re ready when you need an ice pack, they can comfort kids after orthodontia work as well as other bumps and bruises.
• relaxation – either hot or cold, the weight of the filling along with added lavender or essential oils can turn a simple reusable heating pad into a wondrous relaxation gift, perfect to tuck into a Spa Gift Basket.

Variations

While our microwaveable heat bags are about the size of an icepack, remember you can make them in different sizes and shapes:

• pocket-size microwave heat pads are great for kid-size booboos and for tucking into pockets as hand warmers.
• sinus eye pillows (about 2 by 7 inches) – These are great for soothing puffy eyes. Keep the cold eye packs in the fridge or freezer for easy use.
• extra long neck wraps – cut your microwavable heat bags long and thin enough to wrap around the neck and shoulders

Supplies Needed

In addition to a sewing machine, you’ll need:

• cotton fabric – Use breathable cotton fabrics in fun colors and patterns. This allows you to make each kid his own heating pad which is super special.
• cotton thread
• uncooked rice, whole corn (dried as what is used in animal feed), cherry pits, or flax seed to fill (Do NOT use Minute Rice)
• scissors and pinking shears
• optional: dried lavender flower – These will add a bit of relaxing scent, but you can also add a few drops of essential oils to the bag prior to use. (Just don’t use it near the eyes if you do.)

Step-by-Step Instructions

1. Cut a rectangle twice the size of your desired heat pack. Mine were 10 x 11 inches. Pink the edges.
2. With right sides together, fold the fabric in half, forming a thin rectangle. Sew two sides together. Reinforce with an extra seam. Turn the case right side out. It should look like a skinny pillow case.
3. Fill the bag with with rice, leaving two to three inches empty at the top. Fold the top inside itself, and sew shut. Sew that seam again to reinforce it.

Tip for success: In my experience, it’s good to heat and cool each rice bag and allow it to dry completely prior to gifting. Initial heating can release a little bit of moisture in the bags.

To use: Just heat the bag for a minute or two in the microwave and use to warm cold beds or sore tummies. It is recommended to place a mug of water in the microwave alongside the heat packs in order to avoid scorching. Store in the freezer to use as a cold pack.

Remember that if you give these as a gift, it’s best to include an instruction card. When my friend Krista gave me one years ago I didn’t know what it was! 

Safety Tips

As always, please use common sense and safety precautions. I am not responsible for fires in your microwave. I am merely sharing our experience and what has worked for us.

• Heat a mug of water in the microwave alongside the bag to prevent scorching.

I could not find specific instructions for bags with the fillings I’ve used. However, I did find these safety reads for bags filled with wheat. I’m not sure how that filling differs from these fillings. Just FYI.

• Safety Guidelines for Wheat Bags from New South Wales
• Safety Guidelines for Wheat Bags from Cheshire, UK

P.S. There is a good round of Q&A in the comments section.

This post was originally published on February 12, 2013. It has been updated for content and clarity.