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Chlorthalidone / clonidine Side Effects

For the Consumer

Applies to chlorthalidone / clonidine: oral tablet

In addition to its needed effects, some unwanted effects may be caused by chlorthalidone / clonidine. 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 chlorthalidone / clonidine:

Signs and symptoms of overdose
  • Difficulty in breathing
  • dizziness (extreme) or faintness
  • feeling cold
  • pinpoint pupils of eyes
  • slow heartbeat
  • unusual tiredness or weakness (extreme)

If any of the following side effects occur while taking chlorthalidone / clonidine, check with your doctor or nurse as soon as possible:

Signs and symptoms of too much potassium loss
  • Dryness of mouth
  • increased thirst
  • irregular heartbeat
  • mood or mental changes
  • muscle cramps or pain
  • nausea or vomiting
  • weak pulse
Signs and symptoms of too much sodium loss
  • Confusion
  • convulsions (seizures)
  • decreased mental activity
  • irritability
  • muscle cramps
  • unusual tiredness or weakness
Less common
  • Mental depression
  • swelling of feet and lower legs
Rare
  • Black, tarry stools
  • blood in urine or stools
  • cough or hoarseness
  • fever or chills
  • joint pain
  • lower back or side pain
  • paleness or cold feeling in fingertips and toes
  • pinpoint red spots on skin
  • skin rash or hives
  • stomach pain (severe) with nausea and vomiting
  • unusual bleeding or bruising
  • vivid dreams or nightmares
  • yellow eyes or skin

Some of the side effects that can occur with chlorthalidone / clonidine 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:

More common
  • Constipation
  • dizziness
  • drowsiness
  • dryness of mouth
  • unusual tiredness or weakness
Less common
  • Decreased sexual ability
  • diarrhea
  • dizziness or lightheadedness when getting up from a lying or sitting position
  • dry, itching, or burning eyes
  • increased sensitivity of skin to sunlight
  • loss of appetite
  • nausea or vomiting
  • nervousness
  • upset stomach

After you stop taking this drug, it is possible that you may still experience side effects that need medical attention. If you notice any of the following side effects check with your doctor immediately:

  • Anxiety or tenseness
  • chest pain
  • fast or pounding heartbeat
  • headache
  • increased salivation
  • nausea
  • nervousness
  • restlessness
  • shaking or trembling of hands and fingers
  • stomach cramps
  • sweating
  • trouble in sleeping
  • vomiting

For Healthcare Professionals

Applies to chlorthalidone / clonidine: oral tablet

General

The most frequent adverse reactions were dry mouth, drowsiness, dizziness, constipation, and sedation.[Ref]

Gastrointestinal

Very common (10% or more): Dry mouth (up to 40%), constipation (up to 10%)

Chlorthalidone:
Frequency not reported: Gastric irritation, nausea, vomiting, cramping, diarrhea, constipation, pancreatitis

Clonidine:
Common (1% to 10%): Nausea, vomiting
Frequency not reported: Parotitis[Ref]

Nervous system

Very common (10% or more): Drowsiness (up to 33%), dizziness (up to 16%), sedation (up to 10%)

Chlorthalidone:
Frequency not reported: Dizziness, vertigo, paresthesias, headache

Clonidine:
Common (1% to 10%): Headache[Ref]

Other

Chlorthalidone:
Frequency not reported: Weakness

Clonidine:
Very common (10% or more): Weakness (up to 10%)
Common (1% to 10%): Malaise, fatigue, discontinuation syndrome
Uncommon (0.1% to 1%): Gynecomastia
Frequency not reported: Dryness, increased sensitivity to alcohol, fever[Ref]

Cardiovascular

Chlorthalidone:
Frequency not reported: Necrotizing angiitis, orthostatic hypotension

Clonidine:
Common (1% to 10%): Orthostatic symptoms
Uncommon (0.1% to 1%): Palpitations, tachycardia, bradycardia
Frequency not reported: Raynaud's phenomenon, congestive heart failure, ECG abnormalities, sinus bradycardia, atrioventricular block, pallor[Ref]

Dermatologic

Chlorthalidone:
Frequency not reported: Purpura, photosensitivity, rash, urticaria, Lyell's syndrome

Clonidine:
Common (1% to 10%): Rash
Uncommon (0.1% to 1%): Pruritus, hives, angioneurotic edema, urticaria, alopecia[Ref]

Genitourinary

Chlorthalidone:
Frequency not reported: Glycosuria, impotence

Clonidine:
Common (1% to 10%): Sexual activity decreased, impotence, nocturia
Uncommon (0.1% to 1%): Difficulty in micturition, urinary retention[Ref]

Hematologic

Chlorthalidone:
Frequency not reported: Leukopenia, agranulocytosis, thrombocytopenia, aplastic anemia

Clonidine:
Frequency not reported: Weakly positive Coombs' test[Ref]

Hepatic

Chlorthalidone:
Frequency not reported: Intrahepatic cholestatic jaundice

Clonidine:
Common (1% to 10%): Mild transient abnormalities in liver function tests
Frequency not reported: Hepatitis[Ref]

Metabolic

Chlorthalidone:
Frequency not reported: Anorexia, hyperglycemia, hyperuricemia

Clonidine:
Common (1% to 10%): Anorexia, weight gain
Frequency not reported: Transient elevation of blood glucose[Ref]

Musculoskeletal

Chlorthalidone:
Frequency not reported: Muscle spasm

Clonidine:
Uncommon (0.1% to 1%): Muscle or joint pain, cramps of the lower limbs
Frequency not reported: Transient elevation of serum creatine phosphokinase[Ref]

Ocular

Chlorthalidone:
Frequency not reported: Xanthopsia

Clonidine:
Frequency not reported: Burning of the eyes, blurred vision[Ref]

Psychiatric

Chlorthalidone:
Frequency not reported: Restlessness

Clonidine:
Common (1% to 10%): Nervousness, agitation, mental depression, loss of libido
Uncommon (0.1% to 1%): Insomnia
Frequency not reported: Vivid dreams, nightmares, behavioral changes, restlessness, anxiety, visual and auditory hallucinations, delirium[Ref]

Renal

Clonidine:
Frequency not reported: Dryness of the nasal mucosa[Ref]

References

1. "Product Information. Combipres (clonidine-chlorthalidone)." Boehringer-Ingelheim, Ridgefield, CT.

Not all side effects for chlorthalidone / clonidine 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. Drugs.com 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.

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