Brief Answer:
Generalized pruritus

Detailed Answer:
Hello XXXXXXX

Generalized itching can come on and not always be explainable. However, if it persists, then he should have a medical evaluation which should include checking his thyroid function (TSH, T4), his liver function, and a complete blood count with a manual differential. A serum tryptase level should be done too.

The usual dose of antihistamine may not be enough. That dose is meant for respiratory allergies rather than skin itching. He may need to double the dose, and even triple it. With the antihistamine Zyrtec (cetirizine) for example, allergists may recommend increasing it up to 6x the usual dose (i.e. 6 pills per day). But I wouldn't do that just yet.

I recommend that your husband increase his allergy medication to double.

It is also important to keep the skin lubricated as dry scratched skin can be further irritating. Use a lotion or cream that is not scented or colored if possible. Some dermatologists recommend using Crisco as it tends to be non-allergenic. It's very heavy, and sometimes can start to get a little rancid over time. Cetaphil, Moisturel, CeraVe or Eucerin Cream are more standard options.

You may need to do a bit of sleuthing to think of if there may be anything that may be contributing to the itching. New soap or detergent? New food, supplement or over the counter medicine? A pet in the house? Also, a recent viral infection (respiratory or gastrointestinal) can sometimes set off itching too.

Even if there is nothing "new", consider changing detergent to a product that is scent/fragrance free, and do not use any dryer sheets in the dryer (those have a number of irritating and potentially toxic chemicals). Use a soap that is fragrance free also if possible.

If the double dose of antihistamine and the above changes have no effect, return to the doctor. Montelukast (Singulair) which is by presciprition,is a leukotriene receptor antagonist for asthma and allergies that can be added to the antihistamine and works by a different mechanism. And while you are there, ask for the lab tests I mentioned.

I hope this information helps. Please let me know if I can provide further information.

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