Brief Answer:
My apologies for the lengthy response, the topic calls for it

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. I would first like to start with possible causes for the generalised rash and itching that your husband is experiencing, and would like to say before listing the causes that in cases with generalised itching we do not always suspect an allergic reaction. So here they are:

+Infections: Bacterial infections, follicle infection, fungal infection, viral infections
+Autoimmune conditions: Systemic lupus erythematosus
+Neuropathic conditions: E.g. herpes zoster, generalised neuropathic pruritis
+Endocrine disorders: Diabetes, thyroid abnormalities, hypoparathyroidism, hypocalcemia, etc.
+Scabies/itch mite
+Food or drug allergies
+Bed bugs, mites, ticks, lice
+Kidney disease
+Liver disease
+Blood: Anemia, lymphoma, leukemia, polycythaemia vera

As you can see ma'am, the search can be long and at times even frustrating. But believe me, with some laboratory investigations and an expert in the field of dermatology we should be able to find the cause for the same. I would thus recommend the following:

+Comprehensive blood count
+Liver function test
+Renal function test
+ESR
+CRP
+RA factor
+ANA
+Cotton swab from the rash sent to the laboratory
+Allergen test (which looks for all the possible allergies your husband could have, this is especially a productive test)
+Physical examination
+Psychological consultation
+Histamine and eosinophil levels
+Urine analysis
+Urine culture and sensitivity examination
+Ultrasound of the abdomen and pelvis
+EKG of the heart

I would also like to ask for the following information ma'am:

+Which areas from your observation are the regions your husband experiences the itching? Would you really consider the location of the itching and rash to be generalised?
+Has your husband experienced depression or is he currently experiencing depression in your opinion? Some time due to numerous or continuous health issues one can develop a low esteem or will to live.
+Have you taken up all the current medications he is on with his PCP and ruled out causes for the allergic reaction?
+Can you get in touch with a dermatologist?
+How would you rate his personal hygiene on a scale of 5, 0 being poor and 5 being excellent
+Does your husband have any other symptoms? (e.g. sensitivity to light, rash on face, weight loss, oral ulcers, joint swelling, shortness of breath, difficulty urinating, etc.)

I can understand how both the investigations and my list of questions can be quite elaborate and lengthy, but sadly ma'am the list of possibilities is too long for me to miss anything. And it would obviously be helpful if I were living in the same region, but I would strongly urge you to schedule an appointment with a dermatologist for now ma'am.

Unfortunately I do not recommend doctors without knowing their reputation and experiencing practice with them personally, so I really cannot recommend a doctor in your region ma'am. I hope you find my response helpful, and I also look forward for your response in order to find some hint toward finding to cause for his presentation.

Best wishes.

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Brief Answer:
Could you do something for me?

Detailed Answer:
Hello once again ma'am.

Thank you so much for your insight.

I have always found speaking to kin of the patient very fruitful as only they can provide a better and unbiased opinion on the cause and symptoms.

I am a care-giver and always think in the patients best interest, but taking into consideration your husbands daily activities and also boredom and the additional information provided by you, I think he should visit a psychiatrist who may be the one to really make the difference.

If you do not mind, I would like to request you to conduct an experiment for me, without your husbands knowledge of course. The next time your husband starts with the itching and complains of the symptoms do the following:

+Get your hands on some anti-histamine (anti-allergy medications), which should be available over-the-counter (OTC) like pheniramine (e.g. advil, poly-histine, trip-histine, etc.)
+Powder one tablet and mix it in a drink that he usually has (e.g. tea, coffee, milkshake, plain milk, etc.); except alcoholic or carbonated drinks
+Observe him for the next 2 hours
+Ask him how his itching and rash is. If he says there is an improvement and the rash and/or itching has at least subsided to a certain extent, if not completely disappeared, then this could indeed be an allergic reaction; but if not then this could be a psychological issue

I hope I have explained things in a manner best understood by you. Please feel free to write back to me for any clarifications or with any extra information, I am always here to help.

Best wishes.

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