Many things can cause dehydration such as having a fever, not drinking enough, vomiting, diarrhea, sweating or exercise. Other common causes of dehydration can be:

• Chronic conditions: Some chronic conditions such as liver, heart, lung disease, or cancer can cause you to not feel thirsty because of changes in your body.
• Medications: Some medications increase the amount of times you need to pee or make you sweat more.
• Treatments: Dehydration is a common side effect of cancer treatments such as chemotherapy or radiation therapy.
• Difficulty swallowing: Can lead to a decreased appetite [not eating much] and not drinking enough. 
• Taste Changes: Because of a chronic condition, medications or some treatments like chemotherapy.
• Pain: Not drinking enough because it is too painful or tiring to get a drink or hold a drink, or go to the toilet.
• Incontinence: Choosing not to drink because of not being able to control when to pee.
• Relying on others: To help you drink or go to the toilet.
• Not being able to tell someone you are thirsty: Because you are sleepy or have difficulty talking.

Managing dehydration works best when you play an active role. 

• Try to figure out if there is a cause for your dehydration. 
• Is it better or worse at different times?
• What helps or makes it worse?

You may want to use a symptom diary to record information about your dehydration. Tracking this information will help you talk to healthcare team about your dehydration.

Physical steps you can try:

• Medication: If you take medication that cause you to pee a lot, continue to take it as prescribed but speak to your healthcare team about your concern of becoming dehydrated so it doesn’t get too bad.
• Eat foods high in water: Some foods contain more water than others. For example, soups and broths, jelly desserts, ice-cream, or sauces and gravies.
• Drink different types of fluids: Fluids can include water, milk, pop, juice, tea/coffee, smoothies, frozen yoghurt and supplements such as Boost® or Ensure®.
• Gentle exercise: If it is safe for you, continue with gentle exercises like walking, swimming, riding a stationary bike every day or gardening. Stop what you are doing though if you feel dizzy, lightheaded or very tired.
• Avoid: Salt tablets, most people get enough salt in their diets. Also, if you are on a high protein diet make sure you drink 8-12 glasses of water each day.
• Limit or stop: Stimulants such as drugs, alcohol, caffeine and nicotine to see if your symptoms go away. These can make your dehydration worse.
• If you care for someone who is dehydrated: If safe to do so, increase choice and availability of drinks. Make drinks more appealing e.g., add lemon/lime or use nice pitchers/glass. Instead of asking “do you want something to drink?” say, “Here is some cool, refreshing water for you”.

Speak with your healthcare team if dehydration is a problem for you. Your worries and questions are important to you and them. Your healthcare team may speak to you about the different medications you can take that might be causing your dehydration.   

• Let them know if you think your medical condition or medications are the reason for your dehydration.
• Let your healthcare team know if a medication is working for you or if you’re having side effects. You may have to try a few different ones to know what works best for you.
• Talk to them before taking over-the-counter medication, including vitamins and herbal remedies.

Tips on sharing your symptoms with your healthcare team:

• Make some notes about your dehydration symptoms and tell your healthcare team about them.
• Has there been a change in your dehydration?
• How bad is it?
• When does it happen and how long does it last?
• What makes it better or worse? What have you tried already?
• Make a list of all the medications you are taking including over the counter medications.