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Conray-400 Side Effects

Generic name: iothalamate

Medically reviewed by Last updated on Nov 2, 2022.

Note: This document contains side effect information about iothalamate. Some dosage forms listed on this page may not apply to the brand name Conray-400.

Applies to iothalamate: injection solution.

Serious side effects of Conray-400

Along with its needed effects, iothalamate (the active ingredient contained in Conray-400) 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 or nurse immediately if any of the following side effects occur while taking iothalamate:

More common

  • Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • bluish color of fingernails, lips, skin, palms, or nail beds
  • chest pain or tightness
  • cough
  • coughing that sometimes produces a pink frothy sputum
  • feeling of warmth
  • increased sweating
  • noisy breathing
  • not breathing
  • pale skin
  • redness of the face, neck, arms and occasionally, upper chest
  • swelling in the legs and ankles
  • trouble breathing


  • Changes in skin color, pain, tenderness, or swelling of the foot or leg
  • chest discomfort
  • dizziness
  • fainting
  • fast, slow, or irregular heartbeat
  • lightheadedness
  • pounding or rapid pulse
  • stopping of the heart
  • unconsciousness

Incidence not known

  • Black, tarry stools
  • blistering, peeling, or loosening of the skin
  • blue-green to black skin discoloration
  • bruising
  • burning, crawling, itching, numbness, prickling, "pins and needles" , or tingling feelings
  • chills
  • collection of blood under the skin
  • constipation
  • deep, dark purple bruise
  • depressed mood
  • diarrhea
  • dry mouth
  • dry skin and hair
  • feeling cold
  • hair loss
  • hoarseness or husky voice
  • itching
  • joint or muscle pain
  • large, flat, blue or purplish patches in the skin
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • muscle cramps and stiffness
  • nervousness
  • painful or difficult urination
  • partial or slight paralysis
  • problems with speech or speaking
  • red irritated eyes
  • red skin lesions, often with a purple center
  • seizures
  • sensitivity to heat
  • sneezing
  • sore throat
  • sores, ulcers, or white spots in the mouth or on the lips
  • sweating
  • swollen glands
  • trouble sleeping
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • weight gain
  • weight loss

For Healthcare Professionals

Applies to iothalamate: injectable solution.


Common (1% to 10%): Pruritus, urticarial, face edema

Uncommon (0.1% to 1%): Erythema, rash

Rare (less than 0.1%): Angioedema, diaphoresis

Frequency not reported: Ecchymosis and tissue necrosis[Ref]


Common (1% to 10%): Nausea, vomiting

Rare (0.01% to 0.1%): Diarrhea, dry mouth, tongue edema

Very rare (less than 0.01%): Dysphagia[Ref]


Common (1% to 10%): Anaphylactoid reactions

Frequency not reported: Dermal manifestations (urticaria with or without pruritus, erythema, maculopapular rash); dry mouth, sweating, conjunctival symptoms; facial, peripheral, and angioneurotic edema; symptoms related to the respiratory system include sneezing, nasal stuffiness, coughing, choking, dyspnea, chest tightness and wheezing, which may be initial manifestations of more severe and infrequent reactions including asthmatic attack, laryngospasm and bronchospasm with or without edema, pulmonary edema, apnea and cyanosis[Ref]

Rarely, these allergic-type reactions can progress into anaphylaxis with loss of consciousness and coma and severe cardiovascular disturbances.[Ref]


Common (1% to 10%): Rhinitis

Uncommon (0.1% to 1%): Coughing, dyspnea

Rare (0.01% to 0.1%): Larynx edema

Very rare (less than 0.01%): Apnea, bronchospasm[Ref]


Uncommon (0.1% to 1%): Hypotension

Rare (0.01% to 0.1%): Thrombophlebitis, tachycardia, ventricular fibrillation, pallor, vasodilation, cyanosis

Very rare (less than 0.01%): Disseminated intravascular coagulation resulting in death; arrhythmia; bradycardia; cardiac arrest, circulatory failure; abnormal ECG; heart block; phlebitis

Frequency not reported: Generalized vasodilation, flushing and venospasm; occasionally thrombosis; severe cardiovascular responses include rare cases of hypotensive shock, coronary insufficiency, cardiac arrhythmia, fibrillation and arrest; extravasation with burning pain; hematomas; vascular constriction due to injection rate; thrombosis[Ref]

These severe reactions are usually reversible with prompt and appropriate management; however, fatalities have occurred.[Ref]


Uncommon (0.1% to 1%): Thyroid function tests indicative of hypothyroidism or transient thyroid suppression in adults and pediatric patients (including infants)[Ref]


Uncommon (0.1% to 1%): Periorbital edema

Rare (0.01% to 0.1%): Conjunctivitis

Very rare (less than 0.01%): Vision disorders[Ref]


Rare (less than 0.1%): Injection side reaction[Ref]

Nervous system

Rare (0.01% to 0.1%): Dizziness; paraesthesia; taste perversion

Very rare (less than 0.01%): Agitation, coma, convulsions, dyskinesia, paralysis, tremor, somnolence

Frequency not reported: Aphasia; syncope, paresis; paralysis resulting from spinal cord injury and pathology associated with syndrome of transverse myelitis; visual field losses which are usually transient but may be permanent; coma and death; headache, trembling, shaking, numbness[Ref]


Very rare (less than 0.01%): Urinary incontinence[Ref]


Very rare (less than 0.01%): Thirst[Ref]


Very rare (less than 0.01%): Involuntary muscle contractions, myalgia, leg pain

Frequency not reported: Spasm[Ref]


Very common (10% or more): Hot flushes, pain

Rare (0.01% to 0.1%): Malaise

Very rare (less than 0.01%): Edema, abnormal crying

Frequency not reported: Chills without fever and lightheadedness[Ref]


Very rare (less than 0.01%): Anxiety[Ref]


Very rare (less than 0.01%): Acute renal failure, decrease in renal function

Frequency not reported: Temporary renal shutdown or other nephropathy[Ref]


Frequency not reported: Red blood cell clumping and agglutination, crenation and interference in clot formation[Ref]


1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. Cerner Multum, Inc. "Australian Product Information." O 0

3. "Product Information. Conray (iothalamate)." Mallinckrodt Medical Inc (2015):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.