Since you have not mentioned any accident that caused this problem, it is probable that you wife is suffering from a minor sprain or a muscle pull. This is a very uncommon problem and usually occurs when the muscles are overworked. A person who uses their right hand and is unused to using their left hand can easily get a muscle pull in their left hand. This generally happens when they use their left hand to carry a heavy bag or do any other work with their left hand that they would not normally do. If the pain is more of a dull throbbing pain, it is very likely that the pain was not caused by a muscle pull but rather a muscle strain. A muscle strain is caused by a slight strain on the muscles and generally clears within a day or two.
There are several home remedies for wrist pain that your wife can use to get rid of this problem. Boil a potato along with its skin and then mash it well. While it is still quite hot apply this mashed potato around her wrist and tie it in place with a thin strip of clean cloth. Potato retains heat for quite a while and this poultice will help to increase blood circulation to the area and promote healing. She may also suffer from a slight inflammation in her wrist and so a cold compress can be used to reduce the swelling. Many people fins that alternating between a hot and cold compress helps to quicken healing as well as reduce pain and inflammation.
A warm water soak too can be very soothing to overworked muscles. Your wife should recline in a comfortable bowl and then immerse her hand in a bowl of warm water. Add a few drops of lavender oil to this water as lavender oil helps to soothe the muscles. She can keep her hand immersed in the warm water for at least 30 minutes to drastically reduce the pain. If there is very little pain and more of an ache a very gentle soothing massage would be very beneficial in relieving the ache. A mixture of equal amounts of coconut oil and olive oil or almond oil is considered to be an excellent massage oil for aches and sprains. However it is important to be very careful when massaging the sprained wrist as undue pressure can aggravate the pain.
If the pain has not subsided within a day or two or if there are signs of increased swelling or discoloration make sure that you take your wife to the doctor as there may be a more serious underlying cause for the pain.
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