During chemotherapy, the best things to drink are water, electrolyte beverages, ginger tea, and protein-rich smoothies. The American Cancer Society recommends 9 to 13 cups of liquid per day during treatment, which is more than most people drink normally. Staying well-hydrated helps your kidneys flush out chemotherapy drugs and reduces the risk of side effects like nausea, fatigue, and kidney damage.
What you drink matters almost as much as how much you drink. Chemo can cause mouth sores, metallic taste, nausea, and appetite loss, so the right beverages can address multiple problems at once.
Why Hydration Matters More During Chemo
Chemotherapy drugs are processed through your kidneys and liver. When you’re well-hydrated, your kidneys can excrete these drugs more efficiently, which lowers the concentration of toxic compounds sitting in your kidney tissue. This is especially important with platinum-based drugs like cisplatin, where dehydration is directly linked to kidney damage. Hospitals often give large volumes of IV fluid before and after these infusions for exactly this reason.
Vomiting and diarrhea, two common chemo side effects, also drain your fluid reserves fast. If you’re losing fluids from either, you need to replace more than the baseline 9 to 13 cups. Sipping small amounts steadily throughout the day is easier on your stomach than drinking large quantities at once.
Water and Electrolyte Drinks
Plain water is your foundation. If you find it hard to drink enough, try keeping a water bottle nearby and setting reminders. Adding a squeeze of lemon or cucumber slices can make it more appealing, especially if chemo has dulled your sense of taste.
Electrolyte drinks are worth adding to the rotation, particularly if you’re dealing with vomiting or diarrhea. Chemotherapy can disrupt your levels of magnesium, potassium, and calcium, and replacing those through what you drink helps your body stay in balance. Look for low-sugar electrolyte options like diluted sports drinks, coconut water, or oral rehydration solutions. Avoid versions loaded with added sugar, which can worsen nausea and aren’t great for your overall nutrition.
Ginger Tea for Nausea
Ginger has solid evidence behind it for chemotherapy-related nausea. A study of 576 cancer patients found that 0.5 to 1.0 grams of ginger daily significantly reduced the severity of acute nausea when used alongside standard anti-nausea medications. That study used capsules, but ginger tea is a practical way to get a meaningful dose. A one-inch piece of fresh ginger steeped in hot water for 10 to 15 minutes yields roughly 0.5 grams of ginger. Two cups a day puts you in the effective range.
If hot beverages bother your stomach or mouth, let the tea cool to room temperature or chill it. You can also blend fresh ginger into smoothies.
Smoothies and High-Calorie Drinks
When eating solid food feels impossible, liquid calories become essential. European nutrition guidelines for cancer patients recommend 25 to 30 calories per kilogram of body weight per day, with protein intake of 1 to 1.5 grams per kilogram. For a 150-pound person, that translates to roughly 1,700 to 2,000 calories and 68 to 100 grams of protein daily.
Smoothies are one of the easiest ways to hit those targets. A base of milk or a milk alternative, a scoop of protein powder, a banana, and a tablespoon of nut butter can deliver 400 or more calories and 25 to 30 grams of protein in a single glass. Greek yogurt, avocado, and oats are other good additions. If you’ve lost your appetite, sipping a calorie-dense smoothie over an hour is often more manageable than sitting down to a meal.
Ready-made nutritional shakes work too. Look for options with at least 15 grams of protein per serving. These are especially helpful on days when you have no energy to prepare anything.
Managing Metallic Taste
Many chemo drugs leave a persistent metallic taste that makes water and other drinks unpleasant. A few tricks can help. Drinking through a straw reduces the smell of the liquid, which is often the bigger problem. Using plastic cups instead of metal ones also cuts down on metallic flavors. Lemonade, citrus-infused water, and sugar-free lemon drops between sips can reset your palate. If drinks taste too sweet, add a splash of lemon juice or try something tart like diluted cranberry juice. Milkshakes, smoothies, and frozen fruit blends tend to taste better than plain liquids when your taste buds are off.
What to Drink if You Have Mouth Sores
Oral mucositis, the painful mouth sores that some chemo regimens cause, makes drinking anything feel like a chore. Temperature matters: cool and cold drinks are soothing, while hot beverages can intensify the pain. Ice chips, popsicles, and chilled smoothies are your best options. Some people find that sucking on ice chips during their actual infusion helps reduce the severity of mouth sores.
Avoid anything acidic (orange juice, tomato juice, lemonade), carbonated, or alcoholic until the sores heal. These irritate the damaged tissue. Honey stirred into lukewarm chamomile tea is one option that may actually help. Some research suggests medical-grade honey can reduce the severity and pain of mucositis.
Caffeine: How Much Is Fine
You don’t have to give up coffee or tea during chemo. The American Institute for Cancer Research notes that coffee is 99 percent water and contributes to your daily fluid intake. The cutoff is roughly four cups per day. Above that level, caffeine’s mild diuretic effect can start working against your hydration goals. Tea has about one-third to half the caffeine of coffee, so you have more room there.
Keep in mind that caffeine can worsen acid reflux and disrupt sleep, both of which are already common during treatment. If you notice either getting worse, scaling back is a reasonable move.
What to Avoid or Limit
Alcohol is the clearest thing to cut back on. It can interfere with the metabolism of painkillers, anti-nausea drugs, and sedatives you may be taking alongside chemo, potentially reducing their effectiveness or increasing side effects. Alcohol also dehydrates you and adds stress to your liver, which is already working hard to process treatment drugs.
High-dose antioxidant supplements in drink form deserve caution. Green tea in normal amounts is generally fine, but concentrated green tea extract can interfere with certain chemo drugs, including bortezomib and erlotinib. More broadly, drinks marketed as “detox” or “superfood” blends that contain high concentrations of botanicals like quercetin, curcumin, or N-acetylcysteine may reduce the effectiveness of several common chemotherapy agents, including cyclophosphamide, doxorubicin, and platinum-based drugs. A cup of regular green tea is very different from a supplement capsule or concentrated extract. Talk to your oncology team before adding any concentrated botanical beverages to your routine.
Sugary sodas and energy drinks are poor choices. They don’t hydrate efficiently, they can worsen nausea, and energy drinks often contain herbal ingredients that could interact with your treatment.
Practical Tips for Getting Enough Fluids
- Sip, don’t gulp. Small amounts every 15 to 20 minutes are easier to keep down than large glasses.
- Rotate your options. Alternating between water, electrolyte drinks, tea, and smoothies prevents flavor fatigue.
- Use a straw and covered cup. This reduces smell, which helps when nausea or taste changes make open cups unpleasant.
- Track your intake. A marked water bottle or a simple tally on your phone helps you know whether you’re hitting 9 to 13 cups.
- Count all liquids. Broth, popsicles, gelatin, and watermelon all contribute to your daily total.
- Front-load your fluids. Drink more earlier in the day if nighttime bathroom trips are disrupting your sleep.