A maculopapular rash causes flat and raised lesions on the skin. Maculopapular rashes usually suggest an infection or allergic reaction to something.

This type of rash is a symptom of another ailment rather than a condition itself. People with a maculopapular rash should consult a doctor, especially if they experience other symptoms, as it could signal a serious illness.

Keep reading to learn more about this type of rash and what treatments are available.

The most distinctive feature of a maculopapular rash is the pattern of macules and papules. A macule is a small, flat, discolored area of skin, and a papule is a small, inflamed, raised lesion. Both measure 1 centimeter or less in diameter.

A maculopapular rash can appear on any part of the body, depending on the underlying cause. It may also spread to other areas.

A maculopapular rash may cause itching at the site of the bumps. It can also cause other symptoms associated with infections and immune reactions, such as:

Anyone who experiences these symptoms should contact a doctor promptly. Some infections that cause a maculopapular rash can be dangerous and may transmit to other people.

The following may cause a maculopapular rash:

Infection

Several bacterial and viral infections are known to cause maculopapular rashes. Some infections associated with a maculopapular rash are:

Allergic reaction

An allergic reaction occurs when the body mistakenly identifies a substance (allergen) as a threat to the body. A maculopapular rash can be a symptom of an allergic reaction.

Other allergy symptoms include:

Reaction to medication

Some people experience an allergic reaction to a prescribed or over-the-counter (OTC) medication.

According to the American Academy of Allergy, Asthma, and Immunology, most reactions occur within hours, or up to 2 weeks, after taking the medication. Some rashes can take up to 6 weeks to develop.

Some examples of medications that may cause maculopapular rashes include:

However, the reaction can occur in response to almost any medication.

The underlying cause of a maculopapular rash may result in complications.

For example, complications associated with an allergic or drug reaction include the risk of anaphylaxis, a medical emergency that can be fatal.

Various viral and bacterial infections can cause complications. The Zika virus, for example, can lead to:

To diagnose the cause of a maculopapular rash, a doctor will ask a person about their general health and any history of illness and allergies. They will ask where the rash started on the body and when it began.

A doctor will also consider:

  • any medications the person is taking
  • the presence of other symptoms
  • recent travel to areas where viral infections are common

The doctor will then perform a physical examination. They may order blood or urine tests to check for infection. Sometimes, they may take a small sample of the rash, known as a biopsy, to examine it under a microscope.

If the rash worsens or does not resolve with treatment, a doctor will likely refer a person to a dermatologist, a doctor who specializes in skin, hair, and nails.

The treatment for a maculopapular rash depends on the underlying cause:

Infection

A doctor will likely prescribe antibiotics for a bacterial infection. However, antibiotics do not work for viral infections.

Sometimes, the virus will have to run its course. People can manage symptoms with rest, fluids, and OTC pain relievers.

However, more severe viruses, such as HIV, will require a treatment program that might include antiviral drugs.

Allergic reaction

The best way to treat an allergy is to discover and then avoid the allergen. Antihistamines, topical creams, and cold compresses can help alleviate symptoms in cases of allergen exposure.

Reaction to medication

If a drug reaction causes the rash, stopping the medication may be necessary. A doctor may be able to offer alternative treatments.

People should not discontinue the use of a medication without first checking with a doctor.

Relief from itching

A doctor may recommend OTC antihistamines or hydrocortisone cream to help reduce the itching caused by a maculopapular rash. Stronger versions of these medications are available by prescription.

It is essential to contact a doctor before treating a maculopapular rash at home so that they can determine the underlying cause.

What is the most common cause of maculopapular rash?

It is unclear what the most common cause of maculopapular rash is. However, it commonly occurs due to a bacterial or viral infection, allergic reaction, or reaction to some medications.

What type of hypersensitivity is maculopapular rash?

A maculopapular rash is typically an immune response and can be a variety of different hypersensitivity types.

Is maculopapular rash the same as hives?

A maculopapular rash is not the same as hives.

Hives develop when the body releases a chemical called histamine, which can happen due to stress, an allergic reaction, pressure on the skin, sunlight, and an overreaction to sweat, heat, or cold.

The rash associated with hives can appear similar to a maculopapular rash. However, the raised spots and patches associated with hives can vary dramatically in size, ranging from a pinhead to a large dinner plate.

A maculopapular rash can develop as a result of viral and bacterial infections, allergic reactions, or as a reaction to some medications.

The outlook for people with a maculopapular rash depends on the underlying cause. Sometimes, the rash is a symptom of a drug reaction or allergic reaction. Avoiding the trigger can clear up the rash and prevent recurrence.

A maculopapular rash due to a virus will usually resolve once the infection goes away. However, some diseases are more serious than others and can cause severe complications. Some, like HIV, have no cure but can be managed with appropriate treatments.

People with a rash should consult a doctor, who can provide a more accurate outlook based on their diagnosis.