Should You Get An IV Hydration Before a Marathon?

You may have seen IV hydration therapy on social media. Influencers tout weekly IVs as the secret for marathon training. Ads promote IV drips before a marathon to promote hydration. Especially if you have experienced dehydration in a marathon, you may be tempted to try IV hydration. This article will delve into IV hydration before a marathon, including if it is actually beneficial, risks associated with IV therapy, and what you can do instead to stay hydrated.

What is the Purpose of IV Hydration?

IV drips are intravenously-administered solutions that contain fluid, saline, vitamins, minerals, and sometimes medications. Marketing claims that IV hydration offers runners a way to “boost metabolism,” “enhance cellular repair,” and rapidly rehydrate. Are those claims actually supported by evidence, or just marketing buzzwords? 

This article will focus on IV drips that can be purchased at spas, mobile companies, and boutiques. An IV administered by a medical professional at a race or hospital is a different scenario – those are medically warranted to treat dehydration. 

The problem with IV hydration? At best, IV drips are a waste of money. At worst, they are risky. (And if you are so chronically dehydrated that you need an IV drip before a race or long run – you have other problems that need to be addressed by a medical professional.) 

Does IV Hydration Help Before a Marathon?

Intravenous fluids do rapidly alter your body’s hydration status. Unlike drinking water, an IV bypasses the swallowing reflex. As a result, IV drips have a different effect on antidiuretic hormones and arterial pressure. IV fluids go immediately into the vascular system, instead of having to pass through the gastrointestinal system. Your body can absorb larger amounts of fluids in a shorter amount of time with an IV. This is why IVs can treat dehydration in a medical setting such as a hospital. 

So yes, you experience rapid rehydration with an IV drip – but does rapid rehydration actually have any lasting impacts on performance? 

Outside of medically necessary situations, there is not sufficient evidence to indicate any superiority of IV drips for athletic performance. According to a 2010 review in Sports Medicine, IV drips only offer a transient improvement in hydration status – lasting only 35 minutes. Once more than an hour passes, IV drips have no proven advantage over oral hydration. 

The 2010 review concluded that IV drips do not confer any additional benefits to performance or thermoregulation. A 2012 review in Sports Health reached a similar conclusion; the researchers also concluded that no sufficient evidence supports the use of IV hydration to prevent muscle cramps.

So, if you visit an IV spa the night before a marathon or long run, you are not receiving any hydration advantage compared to drinking water or sports drink in adequate amounts. Any benefits of rapid rehydration are over well before you start your race. 

What Ingredients Are In an IV Drip?

Some companies include Toradol (generic name: ketorolac) in them for pain relief. Toradol is an NSAID pain reliever – and is otherwise only available with a prescription. 

Toradol interacts with various medications, such as prednisone and blood thinners. Additionally, breastfeeding women should not take Toradol due to the potential risk it poses to infants. According to the FDA, ketorolac also increases the risk of adverse gastrointestinal events, such as perforation, ulcers, and bleeding. 

Other ingredients included in IV drips include B vitamins, vitamin C, glutathione, and magnesium. Both vitamin C and B vitamins are water-soluble vitamins, which means that typically, you excrete excess amounts in urine. While you are not likely to take in harmful megadoses, you are likely to have very expensive urine.  

It’s worth noting that there are no regulatory standards for IV hydration at spas and boutiques. There is always a risk, as with supplements, that an IV drip could contain ingredients not listed (including banned substances) or not contain effective amounts of the ingredients it claims. 

The Risks of IV Drips for Runners

The above-cited 2010 review draws attention to a potential risk of IV drips for runners: hyponatremia. Hyponatremia is a potentially fatal condition in which over-hydration leads to low serum sodium levels. 

IV drips may increase your risk for hyponatremia since they do not alter your thirst mechanism in the same manner that oral hydration does. You may finish the IV drip and then proceed to feel thirsty – and accidentally ingest too much water. When you receive IV hydration outside of a medical setting, there is always the risk that you could receive too much fluids. 

Is IV Hydration Before a Marathon Prohibited?

The World Anti-Doping Agency (WADA) prohibits the use of IV drips before competition. In their 2018 statement, WADA prohibits the use of “intravenous infusions and/or injections of more than a total of 100 mL per 12-hour period except for those legitimately received in the course of hospital admissions, surgical procedures, or clinical investigations.” If the athlete uses IV drips in legitimate scenarios, they do need to apply for a Therapeutic Use Exemption (TUE). 

This prohibition applies to both in-competition and out-of-competition IV use. If the IV drip is less than 100 ml, it is permissible so long as it does not contain any other prohibited substances. 

When are IV Drips for Runners Appropriate? 

In cases of medically severe dehydration, IV drips will aid in rapid rehydration. This is why they provide an IV drip if you are hospitalized for dehydration, stomach viruses, or similar conditions. However, even minor rehydration does not require an IV drip for treatment. If you require IV therapy for dehydration, a medical team should administer it.

A Safer Alternative: Hyperhydration Strategies

If you are concerned about hydration before training in the heat or a race, there are effective and safe alternatives to IV drips. Hyperhydration with sodium is a safe – and cheap – alternative to IV drips. 

As outlined in a 2023 review in Sports Medicine, hyperhydration is a safe strategy that does lead to lasting changes in hydration status. A hyperhydration strategy the day before a race will improve plasma volume and work capacity for the following day – longer than the potential benefits of an IV drip last. Hyperhydration can also enhance thermoregulation during exercise in the heat. 

Hyperhydration is simple: you use larger doses of sodium, combined with water, to trigger fluid retention. Sodium impacts plasma osmolality and stimulates antidiuretic hormone secretion. This means it helps your body hold onto more fluid. 

You can any high-sodium sports drink for hyperhydration. Liquid IV, Skratch High-Sodium Sport Drink, and LMNT are all options for hyperhydration. You have one of these the day before your race or long run in the heat. Unlike carb-loading, doing hyperhydration for more days is not advantageous, as your renal system adjusts accordingly.

Key Takeaways on IV Hydration Before a Marathon

• IV drips are not necessary before a marathon, long run, or race. You will be able to hydrate with fluids and electrolytes. 
• IV drips do not offer any additional hydration benefits, especially when taken more than an hour before exercise
• The World Anti-Doping Agency has banned IV hydration before races.
• IV drips may contain ingredients such as painkillers that come with a risk of side effects. 
• There may be a risk of hyponatremia (over-hydration) with IV drips. 
• Even if you don’t have adverse effects, IV drips mostly result in very expensive urine.