Furosemide, sometimes prescribed under the brand name Lasix, is a potent
diuretic, or water pill.

It is used to treat high blood pressure as well
as a number of serious conditions in which fluid builds up in body tissues

Side Effects and Interactions

People on furosemide may feel dizzy or faint if
they stand up rapidly.

Older people especially may need to take care to
avoid falling when they first get up.

Increased frequency of urination
is common but may be less bothersome if you take your medicine at breakfast
rather than at night.

Other adverse reactions to be alert for include
rash, itching, sensitivity to sunlight leading to sunburn, ringing in the ears,
nausea, diarrhea or constipation, muscle cramps, hearing loss, unexplained sore
throat with fever, bruising, blurred vision, loss of appetite, increases in
blood sugar, headache, gout and tingling or numbness in hands or feet.

Report any symptoms to your physician promptly.

Furosemide can
interact with a number of other medications. Lanoxin
and other digitalis heart medicines may cause abnormal heart rhythms if
potassium levels are decreased by diuretics.

Indocin, Clinoril, href="http://www.peoplespharmacy.com/2000/04/01/ibuprofen/">ibuprofen,
and activated charcoal may interfere with the effectiveness of furosemide.

At high doses, furosemide can increase the activity of the blood thinner

Adding furosemide to thiazide diuretics may deplete the body rapidly of
fluid and minerals, and calls for careful monitoring.

can greatly increase potassium loss in people taking Lasix.

Lasix and
other potassium-wasting diuretics are probably incompatible with the herb href="http://www.peoplespharmacy.com/2005/10/18/cascara-sagrada/">cascara sagrada, at least if it were used more than very occasionally. Cascara
sagrada, like other strong laxatives, may reduce the absorption of other
medicines taken orally.

(latex) might be dangerous for anyone taking Lasix because of an additive
effect. It should be avoided in such situations.

Check with your doctor
and pharmacist to make sure furosemide is safe in combination with any other
drugs or herbs you take.

Special Precautions

Like many diuretics, furosemide depletes the body of potassium and other important minerals. People taking this medicine may need to include potassium-rich foods in their diet.

Vegetables such as potatoes, beets, brussels sprouts, spinach, cabbage, broccoli, carrots, peppers and squash are good sources of potassium. So are apricots, strawberries, bananas, oranges, peaches and plums.

Most fish also provide good quantities of this mineral.

Some people may not be able to maintain adequate potassium levels even with a diet rich in fish, fruits and vegetables.

Periodic blood tests are crucial to monitor potassium levels in the body. If such a test shows that potassium levels are low, your physician may recommend you cook with a potassium-based salt substitute or he may prescribe a potassium supplement.

Taking the Medicine

Furosemide is absorbed most completely when it is taken on an empty stomach.

This medication may cause stomach upset, however, which tends to be less of a problem when it is taken with food or milk. As the dose should be adjusted individually, with the help of blood tests, let your doctor know if you will change the way you take this drug.

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  1. JLH

    Father 95 prescribed Lasix about a year ago. Received 4 phone calls from MD office to stopped immediately after labs were reviewed. Cardiologist has now put him on the same med. No labs have been done for months and Dad was given a six month return appointment. I refused to give Lasix without an earlier return appointment. Never got the chance to talk with the MD. Office? nurse talked with me and kept insisting Dad take the med. I told them I wasn’t comfortable giving it and wouldn’t without an earlier appointment for follow up. No one suggested I be alert to certain responses from him that might be considered negative. It has been three days now and I have been researching Lasix thru NIDDK. Don’t know what else to do. Dad really thinks this guy walks on water. I don’t.

  2. pj ertman

    what other diuretics are available?

  3. JM

    My doctor prescribed Voltaren for my arthritis but it caused a pretty severe water retention issue. It got to the point I was barely able to walk as my feet hurt so badly. He prescribed Lasix as a diuretic and in less than a week my thighs, legs, ankles and feet are just about back to normal. So far I’ve lost over 10 lbs of water buildup. However, I have experienced some side effects. I’ve experienced nausea, lack of appetite, headaches and a big increase in my existing depression. I am taking them once a day but only for a week then once a week after that. Be prepared for MANY trips to the bathroom to pee. My HR lady saw how nauseous I was and sent me home for a week while I am taking it.

  4. Lourens B.

    Works but causes extremely painful and difficult urination for some hours. Have been using for about 25 years or more. Prostate extremely enlarged. No cancer revealed by biopsy. Would use alternative if available.

  5. N

    My husband has edema, taking lasix generic with potassium. Our concern, when using Lasix and potassium is that this is dangerous to his health. We would like to find a natural substitute. Once I took some potassium and on the bottle label it advised not to use for more than a week at a time.
    Thank you,
    PEOPLE’S PHARMACY RESPONSE: Because furosemide (Lasix) can deplete the body of potassium, doctors often prescribe them together. The physician should be monitoring the blood level of potassium to make sure that it stays within a healthy range. This is quite a different situation from a person deciding to take it as a supplement on her own.

  6. Barb

    Because furosemide blocks potassium and other minerals inside the cells of your body, it draws excess fluid out and can help lower blood pressure, reduce edema, etc. One thing that many people never think of, when taking this kind of drug, is that this has a drying effect on the entire body. You may suffer from constipation, dry sinuses, dry eyes or mouth and yes, dry ears! The body is still producing “wax” in the ear canal but it’s very dry and compact and easily becomes impacted in the ear canal and/or eustacian tube (above your cheek bone), as it is difficult for your body to move that wax out of the ear.
    Most people, without thinking, reach for the Q-tips. WRONG thing to do! This causes the impaction to become severe. If your husband has not already done so, try irrigating the ear canal with warm water and a bulb syringe. NEVER put a cotton swab (or other item) into your ear canal! If the impaction is particularly severe, you may need to irrigate many times before the blockage dissolves enough to be expelled. Have patience, but don’t give up. Many doctors miss this! Best of luck.

  7. tracy s.

    I started furosemide 40mg once a day second dose caused shortness of breath and shock. I have severe pulmonary valve condition, went to A&E put on assessment ward, because of my condition and breathing problems my consultant upped my dose to 40mg twice a day took last dose 12pm went home suddenly feet went blue stayed few hours went to bed woke up half an hour later with severe cramp in my feet got to the top of the stairs the blood rushed from my head I collapsed numbness around my head tingling in arms and legs burning feeling on forehead, side of face, chest and hearing loss. Couldn’t concentrate very cold, surgery’s were closed I couldn’t get any help went to A&E. 4hour wait sent home vitals because vitals were fine.
    Saturday felt unwell pressure in head bad concentration blurred vision numb ears and ringing weak arm and leg numb face, loose stool, gas in stomach [bubbling] burping numbness moves around my face and head and feeling so unwell I went back to A&E Sunday with breathing difficulty I thought I was going to die for the second time. The first nurse said it looks like a panic attack I wanted to scream. Then I saw a doctor who said yes it sounds like you’ve had a reaction they couldn’t do anything.
    He couldn’t give me a new med for the water which was given so my heart didn’t have to work as hard by this time its been put through an olympic sport. Went home still suffering side effects. Monday saw GP waiting for consultant to say which med I can have and dose, I’m dreading the next med. I need to be well for an angiogram then heart surgery. I was born with this condition and I’ve never took meds before I’ve never felt so ill and lost with no one to help and its Tuesday now my symptoms are still unwell with pressure in the head dizzy numb arms and fingers cold feet balance and co-ordination vision and numbness on left side of face feeling of lump in throat how long does this last? If anyone can help please comment.

  8. EV

    I take prescribed 20 mg Lasix twice a day. One Dr. says to take potassium with it–another Dr. says not to. I don’t know what to do.

  9. CJN

    My wife (54 years old) WF. started Furosemide 20mg twice a day for fluid retention. It has helped with that but, has caused her to have hearing loss in both ears. She has been told to stop for two weeks and see her doctor for blood work afterwards

  10. BG

    My husband has suffered hearing loss. He was taking Furosemide and Revatio and has suffered hearing loss plus other side effects such as fainting, appetite loss, etc. He stopped taking them. Has not recovered hearing.

  11. Sherri

    My husband had been trying to get double hernia repaired. Doctors said his blood pressure was a problem and he would end up in the hospital from medicine side effects. He would give up on operation but finally it got so bad that he just let doctors experiment (we’re talking about many doctors because no one seems to treat the whole body).
    He finally got the hernia operation, but doctors are still after him to take meds that make us nervous. His blood pressure has been fine until three days ago when at doctors office it was 140/80. (When we got home it was 125/75). The doctor however had given RX for double the Furosemide he had been taking.
    I frankly am afraid he is going to end up in hospital again! I would like to hear more info on this drug. He fortunately works close to home because he urinates on himself because he can’t make it to bathroom. He does operate heavy equipment at times and the dizziness thing is scary too.

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