Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Aczone (Dapsone-topical). If you are concerned about side effects, discuss the risks and benefits of Aczone (Dapsone-topical) with your doctor.

The following side effects have been reported by at least 1% of people taking Aczone (Dapsone-topical). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• dry skin
• redness
• oily skin
• peeling

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• severe vomiting
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of infection (Fever, severe chills, sore throat, mouth ulcers)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of an allergic reaction (e.g., rash, Hives, swelling of the lips or face, difficulty breathing)
• signs of methemoglobinemia (e.g., headache, fatigue, dizziness, shortness of breath, grey or bluish skin colour, especially of lips, mouth and nail beds)
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• thoughts of self-harm

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Aczone (Dapsone-topical).

Each gram of aqueous gel contains 5% of dapsone (w/w). Nonmedicinal ingredients: carbomer 980, diethylene glycol monoethyl ether (DGME), methylparaben, sodium hydroxide, and purified water.

Do not take Aczone (Dapsone-topical) if you are allergic to dapsone or any ingredients of the medication.

There may be an interaction between dapsone topical and any of the following:

• Acetaminophen
• anti-malarial medications (e.g., chloroquine, hydroxychloroquine, Primaquine)
• benzocaine
• benzoyl peroxide
• Celecoxib
• Flutamide
• nitrates (e.g., isosorbide dinitrate, isosorbide mononitrate, Nitroglycerin)
• lidocaine
• Metoclopramide
• nitric oxide
• Nitrofurantoin
• Phenazopyridine
• Phenobarbital
• Phenytoin
• prilocaine
• pyrimethamine
• quinine
• rifampin
• St. John’s wort
• sodium nitrite
• sulfadiazine
• sulfamethoxazole
• Sulfasalazine
• tetracaine
• Trimethoprim
• Zopiclone

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Aczone (Dapsone-topical). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Aczone (Dapsone-topical).

Blood counts: When taken in the pill form, dapsone can cause decreased numbers of neutrophils (a type of white blood cell that helps fight infection) and red blood cells. This is not expected to occur with dapsone topical gel, but if you experience signs of infection (e.g., fever, chills, or sore throat) or anemia (e.g., fatigue, paleness), stop using the medication and contact your doctor immediately.

Glucose-6-phosphate dehydrogenase deficiency (G6PD): People who lack the enzyme G6PD may be more at risk of developing anemia. If you have G6PD deficiency, discuss with your doctor how Aczone (Dapsone-topical) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Aczone (Dapsone-topical), and whether any special monitoring is needed.

Other acne treatments: Applying any medication containing benzoyl peroxide at the same time as applying dapsone topical gel can cause the skin to temporarily yellow or orange. The use of other topical acne medications may cause increased irritation to the skin.

Methemoglobinemia: There have been reports of methemoglobinemia in people using Aczone (Dapsone-topical). Methemoglobinemia is a condition in which an abnormal level of methemoglobin is produced in the blood, resulting in less oxygen reaching tissues in the body. People with G6PD deficiency and a history of methemoglobinemia should avoid using Aczone (Dapsone-topical). If you develop bluish or grey lips, mouth, or nail beds, contact your doctor immediately.

Pancreatitis: When taken in the pill form, dapsone can cause inflammation of the pancreas (pancreatitis). This is not expected to occur with dapsone topical gel, but if you experience symptoms of pancreatitis, such as persistent low-grade fever or abdominal pain, nausea, or vomiting, stop using Aczone (Dapsone-topical) and contact your doctor as soon as possible.

Self-harm: Although rare, there have been reports of people having suicidal thoughts or wanting to hurt themselves while taking Aczone (Dapsone-topical). If you experience these side effects or notice them in a family member who is taking Aczone (Dapsone-topical), contact your doctor immediately. If you have a history of Depression or other mental illness, you should be closely monitored by your doctor for emotional and behaviour changes while taking Aczone (Dapsone-topical).

Severe skin reactions: When taken in the pill form, dapsone can cause severe skin reactions. This is not expected to occur with dapsone topical gel, but if you experience symptoms of fever, blistering, redness, or peeling, stop using Aczone (Dapsone-topical) and contact your doctor as soon as possible.

Pregnancy: Aczone (Dapsone-topical) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Aczone (Dapsone-topical), contact your doctor immediately.

Breast-feeding: Aczone (Dapsone-topical) passes into breast milk. If you are a breast-feeding mother and are using dapsone topical gel, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Aczone (Dapsone-topical) have not been established for children less than 12 years old.