Generally, kittens can start being dewormed after 6 weeks of age. Kittens under 6 weeks old have a lower chance of being exposed to and infected with parasites, and their gastrointestinal tract is more fragile and its functions are not yet fully developed, and their skin is also more sensitive. Oral internal deworming and external deworming medications have a relatively high probability of causing damage to the kitten's gastrointestinal tract or skin. 
When to vaccinate kittens:
Kittens can start receiving the feline triple vaccine after two months of age. They can receive the rabies vaccine after three months. This is because maternal antibodies in kittens largely disappear after two months, and vaccination at this time prevents these antibodies from negating the vaccine's effectiveness. It's important to note that kittens also need a booster shot annually after their initial vaccinations: one feline triple vaccine and one rabies vaccine, spaced approximately eleven months apart.
