Hydrochlorothiazide is a diuretic or water pill. It helps lower blood pressure. It also helps with swelling from fluid buildup (edema) caused by some health conditions, like heart failure and kidney problems. People of all ages can take hydrochlorothiazide tablets and capsules. But children typically take much smaller, weight-based doses. You typically take your dose by mouth once (sometimes twice) daily, but avoid nighttime dosing so you won't wake up to urinate. Some common side effects are dizziness and urinating more often.
Swelling in the body from fluid buildup (edema)
Hydrochlorothiazide is a type of water pill called a thiazide diuretic. It works in the kidneys to move extra water and certain electrolytes into your urine. This helps remove extra water from your body. As a result, it helps lower blood pressure and reduce swelling in the body.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
Back, leg, or stomach pains
black, tarry stools
bleeding gums
blistering, peeling, or loosening of the skin
blood in the urine or stools
blue lips and fingernails
blurred vision
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
chest pain or tightness
chills
clay-colored stools
cloudy urine
cold sweats
confusion
cough or hoarseness
coughing that sometimes produces a pink frothy sputum
coughing up blood
cracks in the skin
darkened urine
decrease in urine-concentrating ability
decreased frequency or amount of urine
difficult, fast, or noisy breathing
difficulty with swallowing
dizziness, faintness, or lightheadedness when getting up from a lying or sitting position
fast or irregular heartbeat
flushed, dry skin
fruit-like breath odor
general body swelling
general feeling of discomfort or illness
greatly decreased frequency of urination or amount of urine
headache
increased hunger
increased sweating
increased thirst
increased urination
indigestion
joint pain, stiffness, or swelling
loss of appetite
loss of heat from the body
lower back or side pain
muscle cramps or pain
nausea or vomiting
nosebleeds
numbness, tingling, pain, or weakness in the hands or feet
painful or difficult urination
pains in the stomach or side, possibly radiating to the back
pale skin
persistent non-healing sore
pink growth
pinpoint red spots on the skin
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
red, irritated eyes
red skin lesions, often with a purple center
red, swollen skin
reddish patch or irritated area
redness, soreness, or scaly skin
seizures
shiny bump
sores, ulcers, or white spots on the lips or in the mouth
sores, welting, or blisters
swelling of the face, fingers, legs, ankles, feet, or lower legs
swollen or painful glands
tenderness of salivary glands
thickening of bronchial secretions
trembling
trouble breathing
unpleasant breath odor
unusual bleeding or bruising
unusual tiredness or weakness
unusual weight loss
vomiting of blood
weakness and heaviness of the legs
white, yellow or waxy scar-like area
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Cramping
decreased interest in sexual intercourse
difficulty having a bowel movement (stool)
feeling of constant movement of self or surroundings
hair loss or thinning of the hair
inability to have or keep an erection
increased sensitivity of the skin to sunlight
loss in sexual ability, desire, drive, or performance
redness or other discoloration of the skin
restlessness
sensation of spinning
severe sunburn
weakness
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Helps getting rid of extra fluid in your body
A first-choice treatment option if you have high blood pressure or heart failure
Dose can be adjusted based on how well it's working for you
Can make you urinate more often
Can cause electrolytes and fluid levels to be out of balance, which can be dangerous
Might not be a good option for people with a sulfa allergy
Hydrochlorothiazide is a water pill that makes you urinate more often. It's best to take the medication in the morning or earlier during the day. Avoid taking it in the evening. This can help make it less likely for you to have to wake up in the middle of the night to use the bathroom.
Hydrochlorothiazide starts working within 2 hours after you take it and can last up to 12 hours. Remember, this medication works by making you urinate more. So, try to be near a bathroom so you can get to it quickly when you need to go.
You might feel dizzy when you first start taking hydrochlorothiazide. This medication can lower your blood pressure, but your body should adjust over time. Be sure to stand up slowly after sitting or lying down to prevent feeling unsteady and falling.
Ask your prescriber how much water you should drink while taking hydrochlorothiazide. It's important to stay hydrated, especially when exercising or when it's hot. This is because you can lose too much water and your blood pressure can get very low. But drinking too much water can be risky if you have certain health problems like heart failure or liver problems.
It's best to limit or avoid alcohol while taking hydrochlorothiazide. This medication can raise the risk of fluid loss because it makes you urinate more. Alcohol does the same thing, so it can raise the risk of dehydration even more.
Hydrochlorothiazide can make your skin more sensitive to sunlight. Make sure to use sunscreen and wear protective clothing when you're outside. This helps lower your risk of sunburns and skin cancer. See a dermatologist for regular screenings for skin cancer.
If you have high blood sugar or diabetes, talk to your prescriber. You might need to check your blood sugar more often while taking hydrochlorothiazide because it can affect your blood sugar. If it stays higher than usual, let your care team know. If you take diabetes medications, they might need to change your dose to help manage your blood sugar better.
Hydrochlorothiazide can sometimes make it difficult to get or maintain an erection. If this happens and it affects your sex life, talk to your prescriber. They might lower your dose or switch you to a different medication altogether.
Hydrochlorothiazide can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Vomiting a lot | Kidney problems | Liver problems | Hot weather | Dehydration
Hydrochlorothiazide works by making you urinate out extra water and electrolytes. As a consequence, it can make your body lose too much fluid and change your electrolyte levels. You could have low sodium, potassium, magnesium, or chloride. If you have liver problems, small changes in fluid and electrolyte levels can put you at risk of liver complications.
You might need regular blood tests while taking hydrochlorothiazide. These tests help check your electrolyte levels. If your electrolytes are low, your prescriber can help manage this problem. For example, if your potassium is low, they might recommend adding more potassium-rich foods to your diet.
Let your prescriber know if you have dry mouth, muscle cramps, a fast or irregular heart rate, or nausea. Also tell them if you feel weak, tired, dizzy, or confused. These can be signs of abnormal fluid and electrolyte levels, and you might need a blood test to check.
Hydrochlorothiazide can sometimes raise your calcium levels. Mild cases of high calcium levels usually don't cause any symptoms. But if it gets very high during treatment, you might notice some side effects. This can include feeling tired, weak muscles, stomach problems, being more thirsty, bone pain, and feeling confused. If you experience any of these side effects, let your care team know.
Very high calcium levels could also be a sign of a problem with your parathyroid. Your care team might want to test your parathyroid to check. But you'll need to stop taking hydrochlorothiazide before the test. Make sure to tell your care team about all the medications you take before you have any lab work done.
Risk factors: Diabetes
Hydrochlorothiazide might raise your blood sugar. If you have diabetes, let your prescriber know. They might want you to check your blood sugar more often.
Tell your diabetes care team if your blood sugar stays higher than usual while you're taking hydrochlorothiazide. The care team might need to adjust your diabetes medications to control your blood sugar better.
Hydrochlorothiazide can raise the uric acid levels in your body. This can cause or worsen gout in certain people. Tell your prescriber if you have a history of gout. Let them know if your joints swell, get red, or hurt while taking hydrochlorothiazide. These could be signs of a gout attack.
Risk factors: Sulfa or penicillin allergy
Hydrochlorothiazide can cause vision changes like blurry vision. It can also cause a sudden eye problem called angle-closure glaucoma, which can be serious. These problems can happen within hours or weeks after starting hydrochlorothiazide.
Be aware of sudden blurry vision or eye pain. If this happens, stop taking hydrochlorothiazide and tell your prescriber right away. If it's not treated, angle-closure glaucoma can lead to permanent vision loss.
If you have kidney problems, let your prescriber know. They can make sure that hydrochlorothiazide is safe for you to take.
In people with kidney problems, hydrochlorothiazide can cause certain waste products to build up in the blood. The body also might not be able to get rid of the medication well. When this happens, hydrochlorothiazide can build up in the body and make it more likely to have side effects.
Adults
High blood pressure: The typical starting dose is 25 mg by mouth once daily. Your prescriber might raise your dose to 50 mg daily, taken either as a single dose or split into two doses per day.
Swelling from fluid buildup in the body (edema): The typical dose ranges between 25 mg and 100 mg by mouth daily. This dose is taken either as a single dose or divided doses throughout the day.
Babies and children
The prescriber will calculate the dose based on your child's weight. The typical dose is 0.5 to 1 mg per pound each day. This dose is taken by mouth either as a single dose or as two divided doses per day.
Children 2 to 12 years of age shouldn't take more than 100 mg per day. And babies younger than 2 shouldn't take more than 37.5 mg per day.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Not making urine (not urinating)
Allergy to "sulfa drugs"
Swelling in the body from fluid buildup (edema)
Swelling due to heart failure or kidney disease
Swelling due to liver disease (taken with other medications) - generic hydrochlorothiazide only
High blood pressure - generic hydrochlorothiazide only
Swelling (edema) due to heart failure, liver problems, or kidney problems
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