Hi,
Dermatologic diseases can present without a rash in conditions such as mild urticaria or aquagenic pruritus, where the levels of histamine are sufficient for a sensory but not a vascular response.
In these cases histamine will be the mediator and so anti-histamine medications like Cetrizine will help.
It could be due to excessive dryness of the skin due to failure of the skin to retain water. An overheated, dry environment may contribute to dryness, leading to fine scaling and cracking of skin. Application of emollients, like soft, white paraffin will keep skin well hydrated and thus relieve the symptom.
Underlying systemic disease such as renal, hepatic, or endocrine disorder and drug hypersensitivity should be ruled out because they too can cause itching.