I need to check my hands rashes ,I think this is...

What is the possible causes of your skin rash ?
1. Excessive sensitivity to food or clothing
2. Environmental factors 
3. Exposure to heat sources
4. allergic reaction 
What to do next :
1. consult a dermatology doctor
2. The first treatment option is topical antihistamines such as Benadryl
3. The second option and in the event of acute allergies, you can use topical cortisone medication to relieve the symptoms of eczema
- If there are accompanying skin infections, antibiotics such as azithromycin should be used
General advices:
1. Use relatively warm water for showering ( not hot water )
2. Avoid expose your son to the sun and heat sources
3. Avoid environmental stimuli for eczema, such as atmospheric or skin contact with a specific thing or food
4. Avoid using any product that has aromatic or irritating ingredients to the skin
What are the necessary tests if the situation continues?
1. Clinical examination by the specialist doctor
2. skin swab culture 
3. IgE test