janism, it depends upon how bad you've been. You may need a few days, a week, or a year of atonement. We can't give you an accurate assessment until you tell us what you've done.
I haven't taken Reclast, but I know this really sweet bone specialist who offers the advice given by gravity--a longer infusion and the advice given by tillymack--fluids and chanduk--fluids and tylenol. Some clinics (in Korea) administer steroids before the injection. loriesco has her steroids in hand just in case. I'd say take the day off and we'll hope that you don't need it.
It seems that people with autoimmune systems fare worse than those without. Here's from the Stanford doctor who doesn't mention steroids, but is otherwise quite interesting
"A opposed to administering the 5 mg of zoledronic acid in 100 mL of D5W and infusing it over 15 minutes, for the past 29 years I have had the infusion nurse at Stanford dilute it into 500 mL of NS, and to infuse the 600 mL of now diluted BP over 60 minutes. TRUST ME!! By diluting it and administrating it more slowly, it improves the renal (kidney) safety.
The othr thing I do is to instruct the infusion nurses to give the patient 650 mg of acetaminophen (Tylenol) during the infusion. Then I tell the patients to take that same dose (two regular strength tablets) with dinner and at bedtime the day of the infusion, with all 3 meals and at bedtime the day after the infusion, and a final (7th) dose with breakfast the 2nd morning after the infusion. This reduces the patient's risk of experiencing a symptomatic APR from >28% to < 1%."