Flushing

Flushing occurs because the blood vessels in the skin dilate. There are various causes.

When flushing is produced by activity of the nerves to the blood vessels it is accompanied by sweating. Agents which act directly on the blood vessels cause dry flushing.

Contents of this information page

• Alcohol
• Food additives
• Eating
• Neurological problems
• Drugs
• Other causes of flushing

Flushing associated with rosacea

Flushing related to alcohol

• There is increased susceptibility in Asians.
• Occupational ‘degreaser’ flush This occurs in workmen drinking beer after exposure to industrial solvents such as trichlorethylene vapour, N,N-dimethyl formamide, and N-butyraldoxime.
• Tyramine or histamine in fermented alcoholic beverages (beer, sherry, wine) may induce flushing.

Some drugs cause flushing when the patient drinks alcohol. These include:

• disulfiram
• chlorpropamide
• calcium carbamide (urea)
• phentolamine
• metronidazole
• cephalosporin antibiotics

Alcohol may cause flushing while mushrooms are consumed, and in patients with the rare tumour, carcinoid.

Flushing related to food additives

• MSG (Monosodium glutamate) (E621 and 622) in large doses may cause "Chinese restaurant syndrome."
• Sodium nitrite (and nitrates) (E249, 250,251,252) in cured meats, frankfurters, bacon, salami, ham, may cause headache and flushing.
• Sulphites (potasssium metabisulfite) (E224) found in beer, cider, wine, desserts, fried and frozen vegetables, fruit juices, frozen prawns and shrimps, and milk products, may cause wheezing and flushing.

Note: E numbers are now on most NZ manufactured foods. However, fermented beverages, delicatessen food and restaurant food do not have to state additive content.

Flushing associated with eating

• Hot beverages.
• Auriculotemporal flushing One-sided flushing, heat, and sweating following parotid gland injury or surgery.
• Gustatory flushing Both-sided flushing, increased salivation, tear production and nasal secretion with no history of parotid gland injury. This may be reproduced by chewing a chili pepper and holding it in the mouth for 5 minutes.
• Dumping syndrome Facial flushing occurs with racing heart, sweating, dizziness, weakness, and tummy upset. Symptoms begin after gastric surgery and are provoked after a meal or ingestion of hot drinks or strong glucose. The syndrome becomes worse after the menopause.

Neurologic flushing

• Anxiety
• Simple blushing
• Brain tumors
• Spinal cord lesions
• Orthostatic hypotension
• Migraine headaches
• Parkinson's disease

Drugs which may cause flushing

• all vasodilators
• all calcium channel blockers
• nicotinic acid (flush may be blocked with aspirin or indometacin)
• morphine
• amyl nitrite and butyl nitrite
• cholinergic drugs
• bromocriptine
• thyroid releasing hormone
• tamoxifen
• cyproterone acetate
• systemic steroids
• ciclosporin

Other causes of flushing

• Drinking Kava
• Scombroid fish (mackerel, tuna, bonito) poisoning: results from bacteria acting on improperly refrigerated fish. Histamine forms in the flesh of the fish. Combined with a toxin known as saurine, it can, when ingested, produce:
  • peppery taste
  • diarrhoea
  • mouth burning
  • hives
  • flushing
  • headache
  • sickness
  • vomiting
  • cramps
  Note: cooking does not destroy the toxin and even canned tuna may produce facial flushing.
  
• Carcinoid tumour with liver metastases (secondaries) due to circulating serotonin
• Phaechromocytoma (an adrenal tumour) due to circulating catecholamines (epinephrine/norepinephrine)
• Systemic mastocytosis, due to circulating histamine and associated with low blood pressure (fainting) and breathing difficulties (bronchospasm).