Check to see if they are getting their usual antihypertensives and what those are. Ask for a BP in both arms and to repeat the arm that gave the high result. If you're worried, examine the patient (for any end organ damage signs) and take a super quick history / chart review to see if there's a reason for the HTN, i.e. Post-op/post-anesthesia, etc. Then, it sorta depends on what setting the patient is in. Monitored setting / ICU? Loads of good options. Psych ward without iv access? Your options are much more limited. Generally on the medicine floors, I take the following approach: if it is a real emergency, transfer to the step down ICU and start iv labetol. If it's just an old person with previously undiagnosed htn an no previous meds? Start amlodipine 10mg po, first dose now, and check vitals q4h X 24h. If they have meds? Titrate them up a little bit. If they're on loads of BP meds and their htn is just provoked by being admitted/post-op/sick? Can add Hydralizine 10mg po q6h prn for Sbp > 160. Etc. There are many ways to skin the cat. We even have sublingual Ramipril for stroke patients who can't swallow safely! Get to know the meds avail at the hospital.