Thank you all for those ideas. My friend just phoned me, that after finishing a tireing week in school, she just started to get the spinning vertigo again. I told her the Calc.Carb. and she diluted one globule of 200C in a glass of water, and used it once. Told her, to wait and see, and if there is any improvement, than shouldn't repeat it. She will call me back in the afternoon, and I will report it to you.
And to the sympthome of "feeling to going insane" - yes, at times of depression, she cried a few times and made her husband promise, not to take her to the psychiatry, should she became insane. She said, at those times she really felt panic, and a strong feeling, that she just should think about it, or she will be going really insane right there. She felt a strong urge to escape somehow from her own self - to get rid of this insanity.
And one addition: she informed me, that even years befor her present problem has started, she found that 2-3 days before menstruation, became almost unbearable to others around her, while she feels others became so unbearably harsh and mean: nothing is good enough for her, and she became suspicious, that others are not liking her, her husband maybe not loving her anymore, and she became very-very irritated. Along with it, she used to feel hopeless, and in despair, with not seeing any future, and "the whole word looking dark". This would just disappear as soon as she starts menstruating, which will start with "unbearable cramps" and for 3-6 hours she is so sick, she can not do anything other than lying on her stomach, with a big pillow tucked in at her bikini-line to releave the cramps. She use warm and strong painkiller to live throug this, but this was always the case since she had started menstruating, only the stron PMS is new (2-3 years).

She called me back, that after she used the water-diluter Calc.Carb. C200, and nothing happened, she was so desperate, that about 1,5 hour later repeted it. And about an hour later the spinning vertigo started to slow, and by now it's gone! She is soo happy with this response, as untill now once the spinning vertigo has started, nothing could stop it for a day to say the least.
What now? Do you think this response mean that we have found the right remedy? If yes, when should she repeat and what potency should she use?

You ask for a very rapid response but you have to know that this pathology or better said dis-ease iss chronic. Take time because effect need several days and deep acting need longer effect. The fact that vertigo in acute state went gradually away is good but she can have flaring up of symptoms. If acute situations as vertigo and deep anxiety state comes up : put one granule calc.carb in water and let her drink many little sips over the dag just to the point it ameliorates and than wait. So take time and believe what is happening. I think we are on the good way but may be we have to increase the dilution after time.

My friend called me, that she started to have discharge from her sinuses, along with a strong lower backache, just where she had been diagnosed with osteoporosis (her doctor told her, that her bones are rather strange: in her lower back the calcium ratio is so low, it should be diagnosed as severe osteoporosis, while at other places, upper in her spine and the femur is strong.). She now can not bend over, only with straight back. And the discharge is yellowish-brown.
I told her not to take other homeopathic remedies, only wait and see.
I think these are good signs. Am I right? And she asked me if she can take remedies, which makes the dicharge more fluid (like ambroxol), but I just don't know.

Good advise. If the nose is running and discharge is evacuating, this is cleaning sinuses. The back pain is also an older story... and if osteoporose diagnostic (??) is concluded... Calcarea Carbonica will work deeper. If the pain is too strong i suggest to repeat the remedy in solution for one day, with little sips untill ameloration. (I know there is a big discussion between some homeopaths but this is my way in helping and not harming)

she ever have discharge as this before in life?

Yes, she had many-many sinusitises, with the same syndromes: discharge, headache if you tap on her forehead, and earlier allt those infections had been "treated" with antibiotics, and 2 times with mechanical cleaning (pushing a hole into the sinuses and washing it out with water).
She insisted, if the discharge shouldn't be more, as it is now coming out only in the morning, after she wakes up.
And the backache: she said, it isn't getting better untill now. She said, it feels similar to the lumbago she had at age 15, and at the same place. The pain irradiates to her hips, down to the outside of the legs.

Try continuing observation. Best is also if symptoms are too strong, repeat in solution but stop when amelioration set in.

She had her spine adjusted by her chiropractor exhusband, and she said, she is fine now.

Ok, good... observe please