Brief Answer: try a drug holiday and see, get assessed by a phys Detailed Answer: Hi XXXXXXX Welcome to health care magic. Tablet Solian per se does not have any significant interaction with tablet diltiazem to increse the weakness but there is a note of caution for use of these medicines together because they can have synergistic effect in reducing the heart rate and heart rate can go very slow that is called bradycardia. If the patient is becoming unduly drowsy and that has started particularly with the start of treatment with solium then I think it is better to withheld Solian at least for 3 - 4 days and see the change of the status; If patient reverses to the baseline alertness then the cause is the drug solian and it should be withheld for further expose her if she remains drowsy despite withhelding this drug then there may be some other cause behind her browsy status like some infection say Urinary tract infection or pneumonia are very common causes of such altered mentation or there may be some electrolyte imbalance like hyponatremia or hypernatremia etc. as a cause for this or at times there can be missed out events like cerebrovascular accident, meningoencephalitis or encephalopathy etc. It will be better if you can review her to a neuro physician or an experienced general physician. Get her clinically evaluated and investigated before you decide on for the treatment or modification of any kind in the treatment. I hope the advice will be helpful for you.

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