Brief Answer:
Information

Detailed Answer:
Hello and welcome,

Hot and cold flashes should be looked into further. Has your husband taken his temperature during these times? This is important to see and document whether he is having any fevers.

Also, has he had any weight loss or other symptoms?

Some of the more common causes of hot flashes include
spicy foods
alcohol
hot drinks
caffeine
being in a warm room
smoking
wearing tight clothing
stress and anxiety
hyperthyroidism
chemotherapy
some medications, especially those for treating the prostate

Is there any pattern to his flashes, such as with food/drinks or other situations that I listed above?

I recommend that he have a blood test for his thyroid function (TSH and T4) and also a complete blood count (CBC) with manual differential (counts the number of each type of white blood cell).

Also, his medications should be explored for possible cause.

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Brief Answer:
Thoughts on this

Detailed Answer:
Also, consider reviewing his medications with his doctor as some medications (and supplements, too) can predispose a person to hot flashes.

In addition, while it isn't typical with hot flashes, periods of feeling cold can sometimes be related to heart problems, but I will assume his doctor has looked into that.

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