Kittens typically need deworming within a few weeks of birth. This is because kittens are susceptible to internal parasites, which can be transmitted from their mothers.
Generally, common internal parasites, such as roundworms and tapeworms, usually live in the intestines of kittens and are ingested from food or infected environments. Therefore, kittens should be dewormed for the first time 2 to 3 weeks after birth.
Specific deworming plans and schedules may vary depending on veterinarian advice and regional customs. It is generally recommended to deworm kittens every 2 to 4 weeks after birth until they reach 3 to 6 months of age. After that, an individualized deworming plan can be developed based on needs and veterinarian advice.

The specific methods and medications for deworming should be selected and used based on the advice of a veterinarian. It is important to use safe and effective deworming medications and to administer them correctly as directed.
Therefore, it is recommended to consult a veterinarian within a few weeks of the kitten's birth to develop a suitable deworming plan and obtain the correct deworming medication and usage instructions.