What to expect from IV fluid therapy for dehydration

A clinician inserts a cannula into a vein, usually in an arm or hand, and selects fluid according to your condition. They may reassess your pulse, blood pressure, alertness, breathing, urine output, thirst, and ability to drink. The drip may be slowed or stopped as your hydration improves. The underlying reason for dehydration, such as vomiting, diarrhoea, fever, heat exposure, or another illness, still needs attention.

Tell staff if the cannula becomes painful, tight, cold, swollen, or wet. Mention medicines, kidney or heart problems, and any continuing fluid loss before treatment begins. Once permitted, take small frequent drinks or oral rehydration solution as advised. Rest away from heat and follow the plan for treating vomiting, diarrhoea, or fever. Do not remove the cannula yourself.

Seek urgent care for confusion, fainting, severe weakness, very little urine, inability to keep fluids down, severe breathing difficulty, or chest pain. While receiving fluids, report new breathlessness, worsening swelling, headache, or a rapidly painful infusion site. Return for review if dizziness, thirst, vomiting, or diarrhoea continues after you leave, because losses may be ongoing.

Ask which fluid is being given, what caused the dehydration, how much you should drink afterward, which symptoms mean you need reassessment, and whether your usual medicines need temporary advice.