Does Shampoo Expire?

If you’ve ever discovered a half-used bottle of shampoo lurking at the back of your bathroom cabinets, you’ve probably asked the question, “Does shampoo expire?” Knowing whether shampoo expires and how to tell when a bottle is past its prime can help ensure you only use fresh products on your hair. 

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    Does Shampoo Expire?

    In a word: yes. Shampoo expires, but the expiration depends on which product you use, the manufacturer, and the ingredients.

    The U.S. Food and Drug Administration (FDA) doesn’t require cosmetic products like shampoo to offer a specific shelf life. Still, it does make manufacturers responsible for determining how long their products last.

    Therefore, you’ll usually see a shelf life or expiration date on your shampoo bottle. Your manufacturer may provide two shampoo expiration dates: one showing how long the shampoo lasts unopened and one showing its shelf life after opening. You can expect your shampoo to work as described and remain safe throughout its stated shelf life.

    How Quickly Does Shampoo Expire?

    Most shampoos last between six and 24 months, although many last longer unopened. We recommend using your custom Prose Shampoo within 6 months of opening. While it is safe to use after that time period, the active ingredients included in your formula become less effective so you may notice different results. 

    You can determine your shampoo’s expiration date by checking for a period after opening (PAO) on the bottle. PAO symbols usually look like small tubs and contain a number showing how many months the shampoo lasts. If your shampoo bottle doesn’t have a PAO symbol, consider contacting the manufacturer for more information.

    What Factors Affect How Soon Shampoo Expires?

    One of the primary factors affecting how quickly shampoo expires is whether you open the bottle. As you might expect, opening a shampoo bottle allows microorganisms inside, such as bacteria and fungi.

    Shampoo is water-based, which makes it an ideal breeding ground for germs once they get inside the bottle. So, unopened shampoo sitting in a cabinet could be good for several years, while you’ll usually need to use opened shampoo within a few months. 

    Exposing bottles of shampoo to sunlight or fluctuating temperatures can also affect how long they last, so keeping them in a cool, dark place can help them stay fresh for longer. Natural sunlight and temperature changes can change the appearance and texture of your shampoo and may eventually lead to a stale smell.

    Does Natural Shampoo Expire Faster Than Synthetic Shampoo?

    Generally, synthetic shampoos last longer than natural shampoos because they contain artificial preservatives called parabens. Parabens effectively kill microorganisms and prevent them from thriving in the moist environment inside your shampoo bottle. 

    However, that doesn’t mean synthetic shampoos are the better option. The FDA states that there’s no evidence to suggest that parabens are unsafe when used in small quantities.

    On the other hand, some research shows that parabens could be endocrine disruptors, affecting the levels of hormones in the body. As most people use multiple cosmetics, it’s hardly surprising that many prefer to avoid paraben-containing shampoos whenever possible.

    Further, shampoos won’t last forever, even with the help of synthetic preservatives. Over time, these preservatives break down and stop effectively eradicating microorganisms. 

    How Do I Spot Expired Shampoo?

    Spotting whether your shampoo is past its prime isn’t always as simple as checking the PAO symbol. Unless you note the date you open a new bottle, you may need to do a little detective work to determine if your shampoo is usable.

    You can often determine whether shampoo has gone bad by checking its appearance. Shampoos containing oils tend to separate when they expire, causing the oily ingredients to part from the water and form lumps or a greasy layer at the top of the bottle. You may also notice color changes.

    Giving your shampoo a sniff can also help you detect whether it’s time to throw it out. Expired shampoo often loses its fragrance and may even develop a foul odor if it’s a long way past its expiration date. 

    If you don’t see obvious signs that your shampoo is off, you may notice that it doesn’t work as effectively when you wash your hair. If it’s no longer working as it should, it’s time to open a new bottle. However, it’s not generally a good idea to test potentially expired shampoo by washing your hair because it could cause scalp irritation.

    Find Your Ideal Shampoo Formula

    Your hair type is as unique as you are, so it makes sense to use a customized shampoo or conditioner designed to suit your hair. Get a Prose hair consultation, and discover the right formula to keep your hair strong and healthy.

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