Here are a few tips that can help make a difference:
1. If it's time to give your Chihuahua a bath, but you ran out of shampoo, do not substitute with a human product. Human shampoo is the wrong pH balance for canines; using it can cause the skin to dry out quite terribly. It's better to skip the bath and wait until you restock your dog's own products.
2. It's important to rinse well after shampooing.
Shampoo is meant to do its job, but then be rinsed away clean. Even top-quality formulas need to be thoroughly rinsed out. If not, any remaining residue will cake on the skin. This can block skin pores, which limit proper air circulation and cause rashes and other irritation.
The best way to rinse out all the suds is to use a spray nozzle.
3. Always read the directions on shampoo bottles.
You may have one that is labeled 'concentrated'. Sometimes this means that you should mix it with water, but other times this simply means that you do not need to use a lot of the product.
4. The timing of baths and shampooing will vary, depending on your Chihuahua's needs.
If there are no issues, shampoo your dog every 3 weeks. If you wait longer than this, body oils will begin to accumulate and a dog can start to smell quite bad. If your Chihuahua is suffering from allergies, itchy skin, or other issues, you can use a specialty shampoo much more often, up to 3 or even 4 times per week. Take care, however, with medicated shampoos; always read the instructions.