IV therapy.
How it works.
How fluids are delivered, what nutrients do in the body and what clinical research can tell us about an infusion.
Explore the scienceWhat is an IV drip?
Intravenous simply means “into a vein”. An IV drip delivers fluid through a small, flexible tube called a cannula. The needle used to place it is removed, leaving the flexible tube in position during the infusion. Depending on the prescription, the solution may contain electrolytes or other ingredients. How a cannula works
This route bypasses absorption in the digestive system. The route affects how quickly an ingredient enters the blood, the concentration it reaches and how it is cleared. These changes are studied in pharmacokinetics.
Vitamin C illustrates the difference. Oral absorption is regulated by the gut; intravenous delivery can produce higher blood levels. This is a well-studied difference in delivery, while the benefit of a particular treatment depends on what is given and why. Research on vitamin C delivery
Formulation, dose and infusion rate
An infusion has several parts: the type of fluid, its volume, the ingredients and their doses, and the rate of delivery. These are clinical decisions. NICE’s hospital guidance places assessment, prescribing and monitoring at the centre of IV fluid care. Fluid assessment and monitoring
Fluid and nutrient functions
Fluids and nutrients have specific roles in the body, from fluid balance to collagen formation and nerve function. Understanding these roles helps explain why the ingredients and doses matter when assessing an IV treatment. The sections below introduce that science; individual recommendations depend on the formulation and your clinical needs.
Fluids and electrolytes
In medical care, IV fluids can replace fluid and electrolytes when a person’s needs cannot be met by drinking or through the gut. Electrolytes are dissolved minerals, and the balance between fluid and electrolytes matters as much as the amount given. The established benefits relate to an identified clinical need; hospital guidance is distinct from elective wellness treatment. The clinical role of IV fluids
Vitamin C and collagen
Vitamin C is needed to make collagen, a structural protein in connective tissue. It also acts as an antioxidant and contributes to normal immune function. The body cannot make vitamin C, so it must come from external sources, ordinarily food. These biological roles explain why adequate vitamin C matters to skin and general health. Vitamin C in the body
Vitamin B12, blood cells and nerves
Vitamin B12 supports red blood cell formation, DNA synthesis and nervous system function. Absorption involves several steps in the digestive tract, so both intake and absorption can matter when someone has a deficiency. Identifying the cause helps determine the appropriate treatment and route. The role of vitamin B12
Magnesium and energy metabolism
Magnesium helps enzymes carry out hundreds of biochemical reactions. These include energy production, protein synthesis, and muscle and nerve function. These are normal nutrient functions; treatment decisions depend on nutrient status and clinical need. Magnesium and cell function
What an infusion does
An IV infusion is the most direct way to deliver fluid and nutrients to the body. Here is what that means for you.
Straight into the bloodstream
Everything in the infusion enters your circulation directly. Nothing is lost to digestion, and nothing depends on how well your gut absorbs it. For some nutrients, including vitamin C, this achieves blood levels that oral doses cannot. Oral and IV vitamin C compared
Fast and complete
The fluid and nutrients are delivered in full during your appointment. Rehydration and replenishment happen while you are with us, not over days of tablets.
Made for you
Your infusion is chosen for you after your consultation. If we think a blood panel would help us choose well, we will say so. Our IV menu and our blood testing are designed to work together, so what you have is based on what you actually need.
What to expect on the day
Eat normally and drink water before you arrive; it makes the cannula easier to place. Wear sleeves that push up easily. During the infusion you sit comfortably, read or rest, and we stay with you throughout. Afterwards, you can carry on with your day.
Before your IV treatment with us
Every IV appointment at Renu begins with a conversation. Before anything is prescribed, we want to understand why you have come, what you hope the treatment will do, and whether it is the right choice for you. This is how we work.
We take your history first
Before any infusion, we go through your health history with you: current medicines, supplements, allergies, any previous reactions, and whether you are pregnant or breastfeeding. It takes a few minutes, and it is not a formality. It is how we decide whether an infusion is right for you and whether anything needs checking first. If we are not satisfied that it is safe, we will tell you.
We explain exactly what you are having
Before you agree to anything, you will know what is in your infusion, the dose, what we expect it to do, the alternatives, the possible side effects and the full cost. We will also tell you who is prescribing and administering it, how you will be monitored during the infusion, and how to reach us afterwards. If anything is unclear, ask. We would rather answer a question twice than leave you unsure.
We will tell you when a drip is not the answer
Persistent fatigue, low mood or unexplained symptoms need a proper diagnosis, not a top-up. If what you describe needs investigating, we will say so and point you to the right place, including your GP. Sometimes a private blood panel with us is the more useful first step.
Suitability and possible side effects
IV therapy involves placing a cannula, and it is not suitable for everyone. We will be straightforward about the risks: discomfort, bruising, vein irritation, leakage and infection are possible, as are reactions to ingredients and fluid or electrolyte imbalance. Our assessment, prescribing and monitoring exist to keep those risks as low as possible. Cannula care IV fluid guidance
Some ingredients need particular care. High-dose IV vitamin C, for example, requires extra consideration if you have kidney disease, a history of kidney stones, an iron-overload condition or G6PD deficiency. We will explain the precautions and aftercare for the formulation you are having. Vitamin C suitability information