Is it safe to use kwell (lindane) shampoo?

Yes. If it wasn't safe, they wouldn't be able to sell it. However, there are some precautions, and it shouldn't be used repeatedly or in infants, children or the elderly. In general permethrine is preferred.

Related Questions

What do I have to do with headlice when it's not removed using kwell (lindane) shampoo?

See doctor. Are there actual live lice present, or just nits? Lindane will kill nits, but can't remove them (they are cemented to your hair, and will just grow out as your hair grows). If there are live lice present, you can consider changing to a Permethrin based lice shampoo, but definitely work on decontaminating your house; wash/dry clothes in hot water and high dry cycle, vacuum, etc. Read more...