Quick Answer:
Most likely the new shampoo formula is combining with existing soap scum, oils, or hard-water minerals and forming a sticky residue in the drain. A simple test is to stop the new product and Switch back to prior shampoo for a week as a test. If the clog clears or stops returning while using the old shampoo, the formula is the likely cause.
Why This Happens
Shampoos contain surfactants, conditioners, oils, silicones and other ingredients. When those mix with leftover soap scum, body oils and minerals in your water they can form a film that sticks to pipe walls and catches hair. Two common patterns are seasonal or temperature-linked behavior. In cold months residue can harden or flow more slowly—Clogs worsen during winter. If a clog only shows up when you run hot water, heat can melt and move softened residue so you see the problem then—Recurring clog only on hot water.
Step-by-Step What to Do
1. Stop the new shampoo and run the test
- Immediately discontinue the new shampoo and Switch back to prior shampoo for a week as a test.
- During the week use only that one product so results are clear.
2. Remove visible hair and screen the drain
- Take off any stopper or grate and remove trapped hair by hand (wear gloves) or with a disposable tool.
- Clean and replace the drain cover or install a hair catcher to prevent more buildup.
3. Flush the line safely
- Run hot tap water for 2–5 minutes to help loosen soft residue (avoid boiling water if your pipes are PVC).
- If flow is still slow, try a baking soda (1/2 cup) followed by white vinegar (1 cup), wait 15 minutes, then flush with hot water. This is gentler than strong chemicals.
4. Use a drain snake or manual auger if needed
- For persistent clogs, feed a small drain snake down the drain to pull out the film and hair. Turn slowly and pull back gently.
- A plastic zip-it tool can work for shallow clogs; avoid forcing metal hangers into pipes.
5. Monitor and document
- Note when clogs appear (time of day, hot vs cold water, after which product). This helps identify if the shampoo is the cause.
- If the clog stops while on the prior shampoo, avoid returning to the new formula or try a sample-size first and monitor closely.
What Not to Do
- Do not mix multiple shampoos while testing. That hides whether one product is the cause.
- Do not pour strong caustic drain cleaners down a bathroom sink or tub; they can damage pipes, finishes and harm you if used improperly.
- Do not force metal hangers into the drain. They can scratch pipes and push clogs deeper.
- Do not use boiling water on plastic (PVC) pipes—use hot tap water instead.
When to Call a Professional
Call a plumber if:
- Drains stay slow after removing hair and trying the safe flush steps.
- Water backs up into other fixtures or you smell sewage.
- The clog returns immediately even when using the old shampoo, or you need a camera inspection to find buildup deep in the line.
Safety Notes
- Wear gloves when removing hair and cleaning drains to avoid contact with bacteria and sharp debris.
- Vent the bathroom when using vinegar or other cleaning agents; never mix bleach with acids like vinegar.
- If you use a snake, follow tool instructions and stop if you feel sharp resistance—call a pro to avoid pipe damage.
- Dispose of removed gunk and hair in the trash, not back down the drain.
Common Homeowner Questions
- Will changing back to my old shampoo fix it? Often yes—if the problem is the new formula, returning to the old product for a week will usually stop the recurring buildup.
- Can I use strong drain cleaners to remove shampoo residue? No—strong caustic cleaners can harm pipes and finishes; try manual removal and gentle baking soda/vinegar first.
- How long should I wait before calling a plumber? If simple removal and flushing don’t help within a day or the clog recurs quickly, call a professional.