Swelling and numbness of the hands should be alerted to the possibility of skin allergy of the hands, or obstruction of venous return of the hands.
If your hands are swollen and numb, especially if they are combined with skin rashes and blisters, it is likely to be caused by a skin lesion, especially if you have recently touched irritating chemicals or plants or animals with your hands.
If necessary, you can visit a dermatologist for an in-person diagnosis. It is usually treated by taking anti-allergy medications such as loratadine and, if necessary, even hormonal treatments such as intravenous dexamethasone.
Carpal tunnel syndrome may affect the venous return to the hands. A large amount of blood and water pooling in the hand can cause swelling; pressure on the peripheral nerves of the hand can lead to numbness.
Venous thrombosis can also cause obstruction of venous return to the hands, leading to swelling and numbness. Tests such as an ultrasound of the blood vessels and X-rays of the hands are needed to help make the diagnosis.
Swelling and numbness in the hands can also be caused by other reasons, and patients are advised to seek medical attention to identify the cause and treat it aggressively.