Brief Answer:
please see discussion.

Detailed Answer:
Dear Madam
Normally a drug is prescribed to a patient after thorough evaluation i.e. it is ensured that patient is fit enough to receive the medication. It is expected that your doctor must have done so in your case. Moreover a dramatic fall of blood pressure is not expected with oral drugs. There may be fall in blood pressure from the baseline but if it is not symptomatic i.e. there are no features of hypotension, nothing much is required to be done. The symptoms of low blood pressure are syncope, dizziness, low urine output, inability to concentrate, lethargy etc. If you encounter any of these symptoms do visit the nearest health care facility. Usually stopping the drug and maintaining adequate fluid volume in body should suffice in such case scenarios.
Hope that helps. Feel free to discuss further.
Sincerely
Sukhvinder

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