What's the Best Thing to Drink Before You Donate Plasma?

November 23, 2025 •

3 min read

According to the American Red Cross, drinking an extra 16 ounces of water before your donation is recommended, but what's the best thing to drink before you donate plasma? The consensus among donation centers and health experts is that water is the ideal beverage, with other options like sports drinks also being beneficial. Staying well-hydrated is the single most important step you can take to ensure a smooth, successful donation.

Quick Summary

Water is the best choice to drink before donating plasma because plasma is primarily water. Proper hydration maintains blood volume, ensures an easier venipuncture, and helps prevent dizziness and lightheadedness. Donors should also avoid dehydrating beverages like alcohol and caffeine for at least 24 hours prior to their appointment for a better outcome.

Key Points

Water is optimal: Drink plenty of water in the 24 hours before and the day of your donation for the smoothest process.
Avoid dehydrating drinks: Skip alcohol and caffeine for at least 24 hours prior to your appointment, as they can lead to dehydration and affect your eligibility.
Electrolyte drinks are beneficial: A sports drink can help replenish electrolytes lost during donation, but monitor the sugar content.
Hydrate early and consistently: Start hydrating one to two days in advance, not just right before, to prepare your body properly.
Combine with a good diet: Eat a low-fat, high-protein meal before donating to boost your energy and ensure usable plasma.
Ensures smoother process: Proper hydration maintains blood volume, which helps with vein access and can speed up the donation.
Reduces adverse effects: Being well-hydrated minimizes the risk of dizziness, fainting, and fatigue during and after your donation.

The Crucial Role of Hydration in Plasma Donation

Plasma is the liquid component of your blood, making up about 55% of its total volume, and is itself over 90% water. When you donate, you are effectively giving away a large portion of your body's fluid. Replenishing this fluid is critical for a safe, comfortable, and successful donation. Inadequate hydration can make your blood thicker, causing the donation process to take longer and making it more difficult for phlebotomists to find a suitable vein. Dehydration can also cause you to feel dizzy, faint, or fatigued after the donation.

Best Beverage Choices for Pre-Donation

While water is the undisputed best option, other drinks can also contribute positively to your hydration and overall readiness for donating plasma.

Water: The most effective and straightforward choice. It provides pure hydration without any diuretic effects, which can increase fluid loss. Aim to increase your water intake in the 24 hours leading up to your appointment, not just the hour before.
Sports Drinks: These are a good option for replenishing electrolytes, which are crucial for maintaining proper fluid balance in the body. Be mindful of the sugar content and opt for lower-sugar varieties to avoid a crash. Electrolyte tablets that dissolve in water are another excellent alternative.
Fruit Juice (Low-Sugar): Some low-sugar fruit juices, particularly citrus juices, can provide hydration along with a beneficial dose of vitamin C, which aids in iron absorption. However, sugary juices should be limited as they can interfere with blood sugar levels.
Herbal Tea: For those who prefer a warm beverage, caffeine-free herbal teas are a suitable choice. They provide fluids without the dehydrating effects of caffeinated drinks.

Comparison Table: Best vs. Worst Drinks for Donors


Feature	Best Drinks	Worst Drinks
Primary Function	Hydration, Electrolyte Replenishment	Dehydration, Vein Constriction
Example	Water, Sports Drinks, Low-Sugar Fruit Juice	Coffee, Alcohol, Energy Drinks
Effect on Donation	Smoother process, faster recovery, easier venipuncture	Potential deferral, slower flow, lightheadedness
Best Time to Drink	24+ hours before and on the day of donation	Avoid at least 24 hours before donation
Key Benefit	Stable blood volume and pressure	No benefits, increases risk of adverse effects

Drinks to Avoid Before Donating Plasma

Just as important as knowing what to drink is knowing what to avoid. These beverages can negatively impact your donation process and your recovery:

Alcohol: Acting as a diuretic, alcohol dehydrates your body and should be avoided for at least 24 hours before your donation. It can also interfere with your blood's ability to clot and affect your vital signs.
Caffeine: Found in coffee, tea, soda, and energy drinks, caffeine is another diuretic that can lead to dehydration and increase your pulse and blood pressure, potentially causing a deferral. It's best to avoid these on the day of your appointment.
High-Fat and High-Sugar Beverages: High-fat beverages, like whole milk or milkshakes, can increase the fat content in your plasma, making it appear cloudy (a condition known as lipemia). This can render the plasma unusable. Sugary drinks can also cause blood sugar fluctuations. Avoid these for at least six hours before your donation.

Hydration Strategy and Additional Preparation

For optimal results, your hydration strategy should begin well before your donation. Start increasing your fluid intake one to two days in advance. On the day of your donation, drink 12 to 24 ounces of water in the hour leading up to your appointment. Combining this hydration with a low-fat, protein-rich meal will set you up for a successful and comfortable experience. Some donation centers even offer saline solutions at the end of the process to aid in immediate rehydration.

Conclusion

What's the best thing to drink before you donate plasma? Plain water is the clear winner, offering the most direct and effective path to proper hydration. Supplementing with electrolyte drinks or low-sugar juices can be beneficial, but the foundation of a successful donation is consistent, sufficient water intake. By avoiding dehydrating drinks like alcohol and caffeine and focusing on hydration and a healthy diet, you can significantly improve your donation experience and ensure your life-saving gift is of the highest quality. Learn more about the plasma donation process from HHS.gov.

Frequently Asked Questions

Water is the ideal beverage because plasma is over 90% water. Drinking plenty of water helps maintain your blood volume, ensures a smoother donation process, and reduces the risk of feeling dizzy or lightheaded.

It is highly recommended to avoid caffeinated beverages like coffee on the day of your donation. Caffeine is a diuretic and can lead to dehydration, affecting your pulse and potentially causing a deferral.

Yes, sports drinks can be a good option because they contain electrolytes that help with faster rehydration and fluid balance. Just be mindful of the sugar content and choose a low-sugar option if possible.

It is recommended to drink plenty of fluids in the 24 hours leading up to your appointment, often suggested as 8-12 glasses of water. On the day of, aim for an additional 16-24 ounces in the hour or so before your donation.

Alcohol is a diuretic that causes dehydration. You should avoid it for at least 24 hours before your donation to prevent dehydration and to ensure your blood's chemistry is not affected.

Yes, proper hydration makes your blood flow more smoothly and can make your veins more visible and accessible. This can lead to a more efficient and potentially faster donation process.

If you are dehydrated, the donation process can be slower, and you are more likely to experience side effects like dizziness or fainting. In some cases, you may be deferred from donating that day.