Hi XXXXXXX

Thanks for writing to us.

To answer your question directly, I read that few constituents of the dark chocolate cannot be tolerated by some people. If intolerable they bring out in the form of one or more of the symptoms like headache, nausea, dizziness.

I hope she is no more on HRT. The effects should have worn off by now.

Let us also continue the discussion with bilateral swollen ankles (termed pedal edema).
Bilateral pedal edema ( swelling of ankles) can be due to various causes.
The probable causes in your mother could be due to electrolyte disturbance, hypoproteinemia( decreased protein in body due to age), prolonged standing, Heat edema ( usually seen in summer and is transient), due to Hormone Replacement Therapy( due to estrogen component) or due to injury. Of course we should also know cardiac reasons as well.

You have not mentioned whether she had any injury or not. Sudden onset of pedal edema could only be due to an injury or prolonged standing. It is also possible that your mother might have had the swollen ankles since many days( may be the edema could be of lesser degree and which might not have been noticed) and you have noticed now as the edema was more. The possibility of electrolyte disturbance has also to be ruled out as you have said that your mother had dizziness.

Relax. Do not worry. your mother should just be fine in the absence of organic disease. Check for other symptoms like breathlessness, wheezing. If they exist she needs a cardiac evaluation and kidney evaluation. It is also good to get a general check for well being. If not associated with any of the above just ask her to sleep with the foot end elevated by placing a pillow under her feet and the pedal edema ( swelling of ankle)should come down. If the edema does not get down then the possibility of other options has to be ruled out.

Feel free to ask doubts if any. Shall be glad to answer them.

Hope you got the answer you were looking for.
Take Care

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