Grandmother on 4 blood pressure medications - still having a fluctuating blood pressure reaching 200/100+. any ideas?

Add meds.: Keep adding medicines until pressure goes down over time. Give appointments every week. Monitor BP at home. Use Clonidine to lower BP higher than 200/100. Even consider Clonidine patch. Refer her to a hypertension specialist, or to a nephrologist ( kidney). Rule out pheochromocytoma.

Workup: She needs a hypertensive workup. Putting patients on BP meds without knowing the underlying problem is simply placing a bandaid on a cut that will never heal on its own. She needs to see a cardiologist who can perform a thorough hypertensive workup.

Need to find cause: She has resistant hypertension and need a throughout workup. Is her potassium low too? You need to know if there is something else causing the hypertension. Primary hyperaldosteronism/cushing's/pheo/thyroid/obstructive sleep apnea/kidney disease/medication side effects...It's time to see a hypertension specialist. The HTN might just be a symptom at this point. Don't just treat the symptoms.