hello and welcome to HCM,
Your doctor has prescribed her the anti vertigo
tablets for temporary control of her giddiness. This is the recommended dose and let her continue the same for a while as giddiness will take time to to get controlled. Her balance system will eventually work out and take care of the giddiness and the tablets just offer supportive treatment till then.
Meanwhile even abnormal Blood pressure can lead to giddiness, so the doctor will aim to regularize the pressure with medication over a period of time and may consider taking her off the anti vertigo drugs.
Keep in mind that the treatment of blood pressure and giddiness is never fast but a slow process. So give some time for the control
Dr Sriram Nathan