How to Wash Period Underwear
If you’re thinking of making the switch to period underwear (or perhaps have already made the leap), one question may give you pause: How do you clean period underwear?
It may seem worrisome to throw blood-soaked underwear in the laundry with other garments. Or you might wonder if they will get the thorough clean they need. Are there specialty care instructions to ensure they maintain their absorbency?
These are all valid questions, but to give you the tl;dr, it’s not really that complicated. With most period underwear, you can machine wash them on cold and tumble dry. So, no big deal. But let’s look at the question in more detail.
What Is Period Underwear
Let’s give a quick explanation of period underwear before we jump into how to care for them. Period underwear is different from regular underwear as it’s designed to absorb menstrual blood (or urine if worn as incontinence underwear.)
Some women rely on period underwear as their only menstrual product. Others wear period underwear as a backup to traditional disposable products (e.g., tampons) to prevent leaks.
Either way, the point is that period underwear is designed to absorb blood. Indeed, some styles can absorb up to 8 tsp (or 8 tampons worth) of blood.
Knix Period Underwear: Our Care Instructions
If you’re a Knix customer (or thinking of trying our period underwear), the care instructions couldn’t be simpler:
- Machine wash cold with mild detergent
- Do not bleach
- Tumble dry on low
Couldn’t be simpler, right? But we get it: You probably have more questions about how to wash period underwear. So read on!
Timing Is Key: Don’t Let Your Period Underwear Sit in a Hamper
While our care instructions don’t specify the window of time you need to wash your underwear; generally, we would avoid letting your used period underwear sit in a laundry basket. They are probably ‘damp’ with blood, so treat them like you would sweaty clothes.
There are a few reasons you might want to get period pants into the washing machine faster:
- They could stain other clothes
- Odor can set in if they sit around as the blood dries and becomes stale-smalling
- In lighter-colored items, blood may cause staining that becomes more difficult to clean once it dries and sets
So, when you’re using period underwear, you might want to stay on top of your laundry a bit more than usual.
You should wash period underwear (just like regular underwear) after each wear. Don’t try to get a second day out of them, even if your flow was lighter than their absorbency. Hygiene is key, so stay clean. This will likely mean that you need multiple pairs of period underwear to get you through the duration of your period.
Period Underwear (Not Limited to Knix): Care FAQs
While the laundry instructions are very straightforward, you probably have a lot more questions about how to care for period panties. So, let’s walk through some of the FAQs.
Please note that if you buy a brand other than Knix, you should follow that brand’s care instructions. However, we’ll try to keep these answers broad enough that they’re helpful no matter what brand you’re trying.
Does Period Underwear Need to Be Rinsed Before Washing?
Rinsing is not an explicit step in our laundry instructions. However, it’s really not a terrible idea—especially if you want to buy some time before you do laundry fully.
If you choose to ring your period underwear, make sure you rinse it under cold water, and you should rinse until the water runs clear. This means you’ll have rinsed away most of the blood (and, therefore, the potential for odor to develop). Gently wring the underwear when you’ve rinsed them and either toss them directly into the laundry or let it air dry until laundry day comes around.
Since you’ve already done half the work, you could also add some detergent and turn the rinse into a hand wash.
- After you’ve rinsed the underwear, leave it to soak for about 30 minutes in some gentle detergent and cold water
- Gently agitate the underwear in the water to get rid of all dirt (not just blood, but sweat, body oil, and residue from moisturizers and other products)
- Rinse well with cold water
- Gently wring and lay flat to dry or hang dry on a washing line
Please note: It is not necessary to hand wash period underwear by Knix, but some people find it more convenient (especially if you don’t have laundry facilities in your home.) Personally, I find hand washing a really lowkey way of staying on top of my delicates - because they’re delicate, it’s not like there’s a lot of vigorous scrubbing involved.
Learn more about how to hand wash underwear here (it’s about bras, but can be applied to all underwear).
Should You Stick with a Delicate Cycle?
In general, underwear is considered delicate and usually kept on a delicate cycle. This applies to period panties too. More importantly, make sure it’s a cold water cycle. Period underwear is made of materials that may become compromised (e.g., lose elasticity) under high temperatures.
A delicate/cold water cycle will help the longevity of your underwear or period panties. There is no real need to use a mesh bag in the washing machine, but if it's something you do, you can do this too.
Now, we get it: Because of the nature of period underwear, you might think that they need to be blasted with hot water in a “heavy soil” cycle. But resist that urge: It will do more harm than good.
If you’re worried about the underwear really coming clean, try rinsing them by hand first (until the water runs clear) and then put them in the machine on a delicate/cold water cycle. See the question above for more information on that!
Are There Specific Steps for Removing Odor in Period Pants?
Odor may set in if period underwear is left lying around soiled and damp. So the biggest thing you can do to avoid odor is to wash them more quickly after wearing them. As previously covered, you can also choose to rinse them to immediately rid them of blood. This will prevent the blood from becoming dry and stale (and assuming that metallic smell we associate with dried blood.)
If odor is a greater concern, you can also look out for odor-busting detergents. There will be many options to choose from. However, take care with harsh cleaners as they can damage delicate undergarments.
If odor is a particular cause of concern for you around your period, you might also want to chat with your doctor about it. Healthy period blood may have a slight metallic smell, but if you consider it foul-smelling, there might be something else going on.
What Type of Detergent Should You Use?
You may notice that your lingerie store sells specialty detergent or lingerie wash for washing bras, delicate underwear, and lingerie. While you don’t necessarily need a specialty lingerie detergent for your period underwear, we personally prefer to use an alcohol-free mild detergent. Some of our favorites include:
- Soak Wash: Manufactured in Toronto, Soak is an eco-friendly, rinse-free wash that cleans beautifully and is ideal for hand or machine-washing underwear.
- The Laundress: The Laundress’ Delicate Wash is ideal for lingerie and other items labeled “dry clean.” This formula removes perspiration, body oils, and stains while cleaning and preserving fabrics.
These are just two options and there are so many great earth-friendly laundry detergents for you to explore. There will be something for every budget!
If you’re dealing with a period blood stain on your underwear, you should still have a gentle approach. Do not be tempted to increase the temperature of your wash. Instead, think about repeating the soaking steps in the hand-washing section above. A soft toothbrush and a little spot treatment with your detergent can also help loosen a stain. As long as you gently rub, you won't pull the delicate fibers.
Fabric Softener with Period Underwear: Yay or Nay?
It’s a hard NO on fabric softener for period underwear (and indeed all underwear.) If you use fabric softener, you may enjoy its effect on cotton towels and bedding. But it can leave a residue on synthetic and silky fabrics. This means it can really run your period underwear (or other performance clothing like leggings.) So give the softener a wide berth when cleaning your undergarments.
How to Treat Blood Stains That Don’t Lift Out in a Regular Wash?
If you have blood stains in period (or regular) underwear or outer layer clothing, there are many time-honored tips for getting rid of those stains. You can read a whole article about getting blood stains out of underwear for more insights. These tips apply as much to period underwear as regular.
The best stain-prevention tip is to act fast. Once a stain dries, it can really set in. This is even more the case if it dries in with heat (i.e., the item has been machine washed and then machine-dried). So, whatever method you choose, your greatest chance of success is when that stain is fresh.
What About Machine Washing Period Panties With Other Items: Could the Blood Stain Other Garments?
We recommend sorting your period underwear with your other laundry by color (darks, whites, colors). Most period underwear will probably end up in the dark cycle, so you will have no concerns about blood staining other garments.
Remember, machine cycles are quite active with washing and rinsing the water away, so you really don’t need to worry that the entire wash is sitting in bloody water. It is completely hygienic to clean period underwear with other items.
Again, if you’re concerned, a quick rinse under cool water before you toss them in the machine (see above) will help alleviate those concerns.
Don’t Let Care Put You Off: Compelling Reasons to Switch to Period Underwear
It’s completely understandable that you’d have questions about how to care for and wash your period underwear. After all, none of us wants more hassle in our lives! Rest assured, period underwear (or, at least, Knix period underwear) doesn’t require special care that will cause you headaches.
Plus, there’s so much to gain from making the switch, including:
Comfort & Confidence 💃
Period underwear won’t force you to compromise on comfort or style. In fact, they can be comfortable and pretty! You don’t need to resort to wearing those ratty old panties that you’re okay with staining.
On lighter days, period underwear can liberate you from panty-liners. It’s also worth noting that insertables (like tampons) aren’t comfortable for everyone. So period undies open up another option.
How many pairs of period pants you need will depend on your menstrual cycle and whether you like to wear them between periods as well. As with any new product, ease your way in. We bet you'll be a convert to absorbent underwear in no time!
Save Some 💰
Feminine hygiene products are not cheap, and many simply cannot afford them. It’s exciting to think how period undies could revolutionize periods for women worldwide. Especially those who may not have access to, or are able to afford, expensive disposable products.
Let’s face it: None of us is wish-listing tampons on our monthly spending! While the initial expenditure may be more, over time, those saved dollars can definitely add up!
Helping the Planet! 🌎
Sustainability is something we all want to improve. Whether you’ve eliminated plastic straws or upped the ante on recycling, most of us are continually looking for ways to reduce waste.
Whether you use pads or regular tampons, applicators or not, disposable period products can create a lot of waste. Even if you don’t wholly eliminate tampons or pads, using them on fewer days can have a positive impact.