Purple shampoo is a popular haircare product used to neutralize brassy or yellow tones in blonde, grey, or silver hair. Many people believe that leaving purple shampoo on the hair for longer than the recommended time will give them faster, better results. But is this actually true? Here’s a look at what really happens if you leave purple shampoo on for too long.
How Does Purple Shampoo Work?
Purple shampoo contains pigments and active ingredients that help neutralize and control brassiness in lightened hair. The pigments are violet or blue in color, which helps cancel out unwanted warm, yellow undertones in the hair strands. Here are the key ways purple shampoo works:
- Deposits pigments: The violet/blue pigments coat the outside of the hair strands to counteract brassiness.
- Cleanses hair: Purple shampoos contain cleansing agents like sulfates that deeply cleanse and strip brassy tones from the hair.
- Tones hair: Active ingredients like salicylic acid or citric acid help brighten hair and boost toning effects.
By using purple shampoo regularly as part of your haircare routine, you can keep blonde, grey or silver hair looking bright and neutralized.
What Happens When You Leave It On Too Long?
Now that we know how purple shampoo works, what actually happens when you leave it on for longer than recommended? Here are some potential effects:
Over-toning
One of the most common issues with leaving purple shampoo on too long is that it can over-tone the hair. The violet pigments continue depositing and building up on the hair strands, taking out too much warmth and brassiness.
This can cause the hair to look and feel unnatural, with an overly icy, greyish, or ashy appearance. Blonde hair can become dingy and discolored. Over-toning occurs because purple shampoo is formulated to be used briefly and then rinsed out so it doesn’t over-deposit.
Dryness
Another problem with leaving purple shampoo on too long is dryness. The cleansing agents like sulfates can start to strip your hair of moisture and natural oils. This can leave hair feeling dry, brittle, and damaged.
Additionally, as the purple pigments build up, they can start to coat the hair shaft too much and cause dryness. Using any haircare product for longer than directed almost always increases the risk of moisture loss.
Irritation
Some people may experience scalp irritation from leaving purple shampoo on too long. Just like over-cleansing with sulfates can dry out the hair, it can also dry out and irritate the scalp.
Those with sensitive skin may notice increased itchiness, redness, flaking, or tightness from the astringent effects of sulfates and acids sitting on the scalp for an extended period.
Damage
In some cases, leaving purple shampoo on for way too long (say over an hour) could potentially cause damage like breakage or split ends. This is because the hair cuticle can start to open up when over-cleansed or over-processed.
Additionally, as the hair becomes drier and more porous from damage, the purple pigments penetrate deeper and become harder to wash out. This cycle of dryness and discoloration can be difficult reverse.
How Long Should You Leave Purple Shampoo On?
So how long should you really leave purple shampoo in to avoid these issues? Here are some general guidelines:
| Hair Type | Recommended Time |
|---|---|
| Blonde | 5-10 minutes |
| Silver/Grey | 3-5 minutes |
| Damaged | 3 minutes or less |
As you can see, purple shampoo should be left on for only about 5 minutes at the absolute max in most cases. Those with damaged hair should limit time to only 1-3 minutes.
Keep in mind, these are recommendations for using purple shampoo all over the head. You can sometimes get away with a bit longer if you are only applying to certain areas like the front hairline.
Tips for Maximizing Results
If you feel like the recommended time isn’t giving you the toning results you want, here are some tips:
- Only shampoo your roots, and let the shampoo run through the ends.
- Shampoo hair while dry before washing as usual.
- Use a toning or silver conditioning mask once a week.
- Use a weaker daily toner instead of strong purple shampoo.
This helps prevent overuse while still neutralizing brassiness. Alternate or space out purple shampoo rather than reaching for it daily.
What If You Leave It On Too Long?
Okay, so you left your purple shampoo on for way longer than the instructions state. Maybe you forgot about it or got distracted and left it on for 30+ minutes. What should you do?
First, give your hair a good rinse under lukewarm water. Use your fingers to help rinse and agitate the hair to remove as much excess pigment as possible.
Next, use a regular shampoo and wash hair as normal to help further strip out the purple shampoo. Follow up with a hydrating mask or deep conditioner for 5-10 minutes to counteract any dryness or damage.
If hair still seems over-toned, try a clarifying or chelating shampoo that removes mineral deposits from the hair. Avoid using any other toning products until hair is back to normal.
Prevention
To avoid overusing purple shampoo in the future:
- Follow instructions carefully.
- Set a timer as a reminder.
- Alternate with non-pigmented shampoo.
- Ask a stylist for guidance if unsure.
- Switch to a daily toner if hair gets over-toned easily.
The Takeaway
If you leave purple shampoo on for too long, it can definitely lead to issues like an overly icy tone, dryness, damage, and irritation. To avoid this, limit application to 5 minutes max for most hair types. Always follow instructions and don’t overdo it.
Purple shampoo works best when used moderately as part of the overall haircare routine. Be patient, and you’ll see results over time without the risk of overuse.