Healthy individuals: 2 liters per week but not always necessary unless extremely dehydrated.

Once per week, however, the vitamins last in your system for 2-3 weeks, unless you have an extremely high metabolism or are severely depleted. 

Heart, liver, or kidney failure, or any medical condition that may increase the risk of fluid overload.

You can do them every 5-7 days. Depending on your weight loss goals, you can do them weekly, bi-weekly, or monthly. Receiving weight loss injections weekly in addition to strict diet and exercise regimen can increase the rate at which you lose weight. Less often injections can still provide weight loss benefits. 

You will feel the effects of the vitamin injection within 24 to 48 hours after injection. Noticing weight loss on the scale is different for everyone since we all have a different metabolism level. Some notice weight loss in a matter of weeks, some in matter of months. 

During your first trimester, you are a candidate for IV hydration and vitamin therapy. However, you can only receive select vitamins since some vitamins are contraindicated during pregnancy. 

While breastfeeding you can receive IV hydration and vitamin therapy, but you must also acknowledge and understand that what you take in can be passed on to baby through your breast milk.