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Bendroflumethiazide / nadolol Side Effects

For the Consumer

Applies to bendroflumethiazide / nadolol: oral tablet

In addition to its needed effects, some unwanted effects may be caused by bendroflumethiazide / nadolol. In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking bendroflumethiazide / nadolol:

Less common
  • Blurred vision
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain or discomfort
  • confusion
  • cough
  • difficulty breathing
  • dilated neck veins
  • dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly
  • extreme fatigue
  • irregular breathing
  • lightheadedness, dizziness, or fainting
  • noisy breathing
  • paleness or cold feeling in fingertips and toes
  • shortness of breath
  • slow or irregular heartbeat
  • slurred speech
  • sweating
  • swelling of face, fingers, feet, or lower legs
  • tightness in chest
  • tingling or pain in fingers or toes when exposed to cold
  • unusual tiredness or weakness
  • weight gain
  • wheezing
Incidence not determined
  • Back or leg pains
  • black, tarry stools
  • bleeding gums
  • bloating
  • blood in urine or stools
  • chills
  • clay-colored stools
  • cloudy urine
  • cold sweats
  • constipation
  • coughing up blood
  • dark urine
  • difficulty swallowing
  • drowsiness
  • dry mouth
  • fast heartbeat
  • fever
  • flushed, dry skin
  • fruit-like breath odor
  • general body swelling
  • general feeling of discomfort or illness
  • general tiredness and weakness
  • headache
  • hives
  • hoarseness
  • increased hunger
  • increased thirst
  • increased urination
  • indigestion
  • joint pain, stiffness, or swelling
  • light-colored stools
  • loss of appetite
  • lower back or side pain
  • muscle tremors
  • nausea and vomiting
  • nosebleeds
  • pain in muscles
  • painful or difficult urination
  • pains in stomach, side, or abdomen, possibly radiating to the back
  • pale skin
  • pinpoint red spots on skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • rapid, deep breathing
  • rash
  • redness, soreness, or itching skin
  • restlessness
  • skin rash
  • sore throat
  • sores, ulcers, or white spots on lips or in mouth
  • sores, welting or blisters
  • stomach cramps
  • sugar in the urine
  • swollen or painful glands
  • tenderness of salivary glands
  • thickening of bronchial secretions
  • troubled breathing
  • unpleasant breath odor
  • unusual bleeding or bruising
  • unusual weight loss
  • upper right abdominal pain
  • vomiting of blood
  • yellow eyes or skin

If any of the following symptoms of overdose occur while taking bendroflumethiazide / nadolol, get emergency help immediately:

Symptoms of overdose
  • Change in consciousness
  • decreased urination
  • diarrhea
  • fast, slow, or shallow breathing
  • gas
  • heartburn
  • increase in heart rate
  • increased sweating
  • indigestion
  • loss of consciousness
  • low blood pressure
  • muscle cramps
  • numbness, tingling, pain, or weakness in hands or feet
  • pale or blue lips, fingernails, or skin
  • seizures
  • sunken eyes
  • trembling
  • unusual drowsiness, dullness, or feeling of sluggishness
  • unusual paleness
  • weakness and heaviness of legs
  • wrinkled skin

Some of the side effects that can occur with bendroflumethiazide / nadolol may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

Less common
  • Change in behavior
  • continuing ringing or buzzing or other unexplained noise in ears
  • decreased interest in sexual intercourse
  • dry eyes or skin
  • excess air or gas in stomach or intestines
  • hair loss, thinning of hair
  • hearing loss
  • inability to have or keep an erection
  • loss in sexual ability, desire, drive, or performance
  • relaxed and calm
  • sleepiness
  • stomach soreness or discomfort
  • stuffy nose
  • weight loss
Incidence not determined
  • Cracks in the skin
  • discoloration of skin
  • feeling of constant movement of self or surroundings
  • increased sensitivity of skin to sunlight
  • large, flat, blue or purplish patches in the skin
  • loss of heat from the body
  • muscle spasm, weakness, or restlessness
  • scaly skin
  • sensation of spinning
  • severe sunburn

For Healthcare Professionals

Applies to bendroflumethiazide / nadolol: oral tablet


Cardiovascular complications of bendroflumethiazide therapy include orthostatic hypotension secondary to intravascular volume depletion. This has resulted in syncope and, in some patients with glaucoma, temporary loss of vision. Rare cases of cerebrovascular accident associated with thiazide-induced diuresis have been reported.

Cardiovascular side effects of nadolol are usually mild and transient and rarely require discontinuation of therapy. Bradycardia, hypotension, conduction disturbances, chest pain, and heart failure have each been reported in 1% to 3% of patients. Complaints of cold extremities have been reported in approximately 5% of patients. Edema has rarely been associated with the use of nadolol.[Ref]

Rare cases of A-V heart block during nadolol therapy have been reported.[Ref]


Dermatologic reactions of bendroflumethiazide may indicate hypersensitivity to the drug. Erythema multiforme, Stevens-Johnson syndrome, exfoliative dermatitis (including toxic epidermal necrolysis), and alopecia have been reported in rare cases.[Ref]


Endocrinologic changes associated with bendroflumethiazide, as with other thiazide diuretic agents, include decreased glucose tolerance and a potentially deleterious effect on the lipid profile. This may be important in some patients with or who are at risk for diabetes or coronary artery disease.[Ref]

A prospective study of 34 patients who received oral thiazide diuretics for 14 years without interruption revealed an increased mean fasting blood glucose level after treatment. Withdrawal of thiazide therapy for 7 months in 10 of the patients resulted in mean reductions of 10% in fasting blood glucose and 25% in the 2-hour glucose tolerance test values. A control group was not reported.[Ref]


Gastrointestinal problems associated with bendroflumethiazide use include anorexia, gastric irritation, nausea, vomiting, diarrhea, constipation, or abdominal pain in approximately 5% of patients. Thiazide diuretics have been associated with acute cholecystitis, intrahepatic cholestatic jaundice and rare cases of pancreatitis.

Gastrointestinal problems, such as nausea, diarrhea, constipation, anorexia, bloating, flatulence and general abdominal upset have each been reported in less than 1% of patients receiving nadolol.[Ref]

A retrospective case-controlled drug surveillance study has revealed the relative risk of acute cholecystitis associated with the use of a thiazide diuretic is 2.0. The suspected explanation for this association is the potentially deleterious effect thiazides have on the serum lipid profile. Bendroflumethiazide-induced hypercholesterolemia or hypertriglyceridemia may enhance the formation of some types of gallstones.[Ref]


Hematologic side effects associated with bendroflumethiazide use are rare. Rare cases of immune-complex hemolytic anemia, aplastic anemia, leukopenia, agranulocytosis, and thrombocytopenia have been associated with thiazide diuretics.[Ref]

Nervous system

Side effects related to the nervous system during bendroflumethiazide administration include mild, transient dizziness, vertigo, xanthopsia, paresthesia, fatigue, or headache.

The most common nervous system side effect of nadolol appears to be fatigue (up to 10% of patients). Headache or dizziness have been reported in 5% and 8% of patients, respectively.[Ref]

Nadolol is hydrophilic and is less likely to penetrate into the central nervous system compared to other beta-blockers. Depression and anxiety are reported in one patient while receiving nadolol. The symptoms started two days after an increase in his dosage and resolved within three days of discontinuing nadolol. Organic brain syndrome was diagnosed in two patients receiving nadolol should be considered as a possible cause of acute deterioration in mental or emotional status.[Ref]


Thiazides may induce allergic reactions in patients who are allergic to sulfonamides.[Ref]

Hypersensitivity reactions with thiazide diuretics usually involve the skin (cutaneous vasculitis, urticaria, rash, purpura), but may involve the gastrointestinal system (nausea, vomiting, or diarrhea), the genitourinary system (interstitial nephritis), and the respiratory system (acute noncardiogenic pulmonary edema, pneumonitis). Thiazide diuretics may induce phototoxic dermatitis.[Ref]


Hyperuricemia may be an important consideration in patients with a history of gout. Hypophosphatemia and low serum magnesium concentrations may occur, but are usually clinically insignificant except in malnourished patients.

Rare cases of hypercalcemia and milk-alkali syndrome (hypercalcemia, metabolic alkalosis, and renal insufficiency) have been associated with thiazide diuretics.[Ref]

Metabolic changes associated with bendroflumethiazide, as with other thiazide diuretics, are relatively common, especially when daily doses greater than 100 mg are used. Mild hypokalemia (decrease of 0.5 mEq/L) occurs in up to 50%, and may predispose patients to cardiac arrhythmias. Metabolic alkalosis, hyponatremia, hypomagnesemia, hypophosphatemia, hypercalcemia, hyperglycemia, hypercholesterolemia, and hyperuricemia are also relatively common.
The electrolyte and intravascular fluid shifts that may occur during bendroflumethiazide diuresis can provoke hepatic encephalopathy in patients with hepatic cirrhosis.[Ref]


Musculoskeletal cramping or spasm are occasionally reported during bendroflumethiazide diuresis.[Ref]


Psychiatric side effects of nadolol have been limited to anxiety-depression in approximately 4% of patients.[Ref]


New or worsened renal insufficiency associated with bendroflumethiazide therapy is a probable sign of intravascular volume depletion, and serves as a signal to reduce or withhold therapy. Rare cases of allergic interstitial nephritis have been associated with some thiazide diuretics.

Renal insufficiency has not associated with nadolol, but one study of 10 elderly hypertensive patients has shown that the antihypertensive effect of nadolol was associated with a decrease in effective renal blood flow. The glomerular filtration rate in affected patients remained stable, however.[Ref]


At least one case of severe bronchospasm associated with nadolol therapy is reported. This patient had a history of childhood asthma and exercise-induced bronchospasm requiring albuterol inhalations. After one dosage of nadolol the patient had a respiratory arrest and required mechanical ventilation for several days. If nadolol is necessary in a patient with a history of bronchospasm, it is recommended that therapy be initiated in a controlled environment with bronchodilators available.[Ref]

Respiratory system side effects associated with nadolol therapy have been rare (1 in 1,000), but may be important in patients with reactive airways disease. The use of nadolol has been associated with precipitation of bronchospasm in patients with a history of asthma.[Ref]


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Not all side effects for bendroflumethiazide / nadolol may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.