Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency

Medications to Avoid / Be Cautious of G6PD

What is G6PD?

G6PD, also known as glucose-6-phosphate dehydrogenase, is an enzyme which helps the body convert sugar to energy. It is found in all cells of the body, but mainly in red blood cells.

Function of G6PD Enzyme

These enzymes help protect haemoglobin in red blood cells from harmful chemicals, to carry oxygen througout the body.

G6PD Deficiency

Deficiency of G6PD enzymes does not usually cause problems or symptoms.

It may, however, become a problem if the person is exposed to certain chemical compounds, or experience certain infections that can cause cells to be destroyed in a process known as haemolysis.

Consequences of G6PD Carriers

People with G6PD deficiency are at increased risk of haemolysis and severe anaemia, due to the breakdown of haemoglobin upon chemical exposure. This condition is known as haemolytic anaemia.

Symptoms of this condition includes pale skin, yellowing of the skin/eyes, dark-coloured urine, fever, dizziness and confusion. Hence, in some cases, short-term treatment involving fluids or blood transfusions may be required.

Preventive Actions by G6PD Carriers

G6PD deficiency is best managed by preventative measures through avoiding certain medications or food. By doing so, serious symptoms can be prevented.

Common Medication to AVOID


  • Chloroquine
  • Mefloquine
  • Pamaquine
  • Primiquine
  • Quinidine
  • Quinine

• Nitrifurans
• Quinolones
• Sulfonamides

  • Nitrofurantoin
  • Ciproflaxacin
  • Levofloxacin
  • Ofloxacin
  • Co-trimoxazole (Sulfamethoxazole + Trimethoprim)
  • Sulfadianzine
  • Sulfanilamide
  • Sulfapyridine


  • Glibenclamide
  • Gliclazide
  • Glimepiride
  • Glupizide

Antineoplastic Adjuncts

  • Doroxubicin
  • Rasburicase

Anti-Rheumatic Agents

  • Hydroxychloroquine


  • Dapsone
  • Frusemide
  • Sulfasalazine

Common Medications


  • Aspirin
  • Paracetamol


  • Phenytoin

Antiparkinsonism Agents

  • Trihexyphenidyl

Cardiovascular Drugs

  • Hydralazine
  • Methyldopa
  • Dopamine

Diognostic Agents

  • Toluidine Blue

Gout Preparations

  • Colchicine
  • Probenecid

Vitamin K Substance

  • Phytomenadione


  • Fave Beans