Hydroxychloroquine: What It Is and How It Works

Buy Hhydroxychloroquine Onlineis a medication with a long and varied medical history. Originally developed to prevent and treat malaria, it has since become a vital treatment option for a range of autoimmune diseases, including rheumatoid arthritis and systemic lupus erythematosus (SLE). More recently, hydroxychloroquine made headlines for its controversial use in treating COVID-19 during the early stages of the pandemic.

But what exactly is hydroxychloroquine? How does it work inside the body? Why is it prescribed, and what precautions should patients be aware of? This article provides a comprehensive overview of hydroxychloroquine—its history, mechanism, uses, and safety profile.

What Is Hydroxychloroquine?

Hydroxychloroquine is a disease-modifying antirheumatic drug (DMARD) and antimalarial agent. It is structurally related to chloroquine, a compound discovered in the 1930s. Hydroxychloroquine was developed as a less toxic derivative and was first approved for medical use in 1955.

It is most commonly known under brand names like:

• Plaquenil

• Hydroquin

• Quinoric

Hydroxychloroquine is available in tablet form, typically in strengths of 200 mg. It is taken orally, often with food, to reduce gastrointestinal side effects.

Medical Uses of Hydroxychloroquine

Hydroxychloroquine is approved or commonly prescribed for the following conditions:

1. Malaria (Prevention and Treatment)

Hydroxychloroquine was initially used to prevent and treat malaria, a parasitic infection transmitted by mosquitoes. However, due to growing resistance among malaria parasites, its use for this purpose has decreased in favor of more modern treatments.

2. Systemic Lupus Erythematosus (SLE)

In lupus, the immune system attacks healthy tissues. Hydroxychloroquine helps suppress the overactive immune response and reduce symptoms such as joint pain, fatigue, skin rashes, and inflammation.

3. Rheumatoid Arthritis

In RA, chronic inflammation causes joint damage and pain. Hydroxychloroquine slows disease progression, reduces flare-ups, and improves long-term joint function when used as part of a DMARD combination therapy.

4. Other Autoimmune Conditions

It may be used off-label in conditions like:

• Sjögren’s syndrome

• Dermatomyositis

• Porphyria cutanea tarda

How Hydroxychloroquine Works

Hydroxychloroquine has multiple mechanisms of action, depending on the condition it is being used to treat.

🔹 Antimalarial Effect

In malaria, hydroxychloroquine accumulates in the parasite’s food vacuoles, interfering with their ability to digest hemoglobin. This leads to toxic buildup and ultimately kills the parasite.

🔹 Immunomodulatory Action

The primary reason hydroxychloroquine is used in autoimmune diseases is its ability to modulate the immune system:

• Inhibits Toll-like receptors (TLRs): These receptors play a role in activating immune responses. By blocking TLRs, hydroxychloroquine reduces inflammation and autoimmunity.

• Alters pH in immune cells: It increases the pH within lysosomes and endosomes, interfering with antigen processing and reducing the immune system’s ability to attack healthy tissue.

• Reduces cytokine production: This helps lower levels of inflammatory proteins like TNF-alpha and IL-6.

Benefits of Hydroxychloroquine

1. Long-Term Disease Control: Especially in lupus and rheumatoid arthritis, it helps control symptoms and prevent long-term damage.

2. Steroid-Sparing Effect: It allows doctors to reduce the dose of corticosteroids, minimizing their side effects.

3. Improves Quality of Life: Helps reduce fatigue, joint pain, and other disabling symptoms.

4. Relatively Well Tolerated: Compared to other immunosuppressive drugs, hydroxychloroquine has a lower risk of severe side effects.

Dosage and Administration

Hydroxychloroquine is taken orally, usually once or twice daily, depending on the condition and severity.

• Typical dosage for autoimmune diseases: 200–400 mg per day

• For malaria prophylaxis: One 400 mg dose once weekly, starting 1–2 weeks before travel and continuing for 4 weeks after leaving the endemic area

It’s important to take hydroxychloroquine with food to reduce nausea and improve absorption.

Side Effects and Risks

Although generally safe, hydroxychloroquine can cause side effects, particularly with long-term use.

🔸 Common Side Effects

• Nausea

• Stomach cramps

• Diarrhea

• Headache

• Dizziness

• Skin rashes

🔸 Serious Side Effects

• Retinal toxicity: Hydroxychloroquine can accumulate in the retina, potentially causing vision problems or permanent damage if not detected early. Regular eye exams (once yearly after 5 years of use) are essential.

• Cardiac effects: Rare cases of cardiomyopathy and conduction disorders have been reported.

• Blood disorders: Such as anemia or low platelet count in rare cases

• Hypoglycemia: It may lower blood sugar, especially in diabetic patients

Precautions and Monitoring

Before starting hydroxychloroquine, patients should:

• Undergo a baseline eye examination

• Have liver and kidney function tests

• Review any other medications they are taking to avoid interactions

While on treatment, doctors may monitor:

• Eye health (at least annually)

• Muscle strength

• Heart rhythm (if used with other QT-prolonging drugs)

Hydroxychloroquine should be used with caution in pregnancy but is generally considered safe, especially for women with lupus to prevent flares.

Hydroxychloroquine and COVID-19: The Controversy

In early 2020, hydroxychloroquine was thrust into the spotlight as a potential treatment for COVID-19. Initial laboratory studies showed antiviral activity, and some early reports suggested benefit.

However, large-scale clinical trials (including those by the WHO and NIH) later found:

• No significant benefit in preventing or treating COVID-19

• Potential for serious side effects, especially related to heart rhythm (QT prolongation)

As a result, emergency use authorizations were revoked, and hydroxychloroquine is no longer recommended for COVID-19 treatment outside of clinical trials.

Conclusion

Hydroxychloroquine is a valuable medication with proven benefits for treating autoimmune diseases like lupus and rheumatoid arthritis. Though its role in malaria has diminished, it continues to be a mainstay in rheumatologic care due to its immunomodulatory effects, tolerability, and ability to reduce disease flares.

Like all medications, hydroxychloroquine must be used with care, especially during long-term therapy, and requires regular monitoring to ensure safety—particularly of the eyes. While it gained controversial attention during the COVID-19 pandemic, its true strength lies in managing chronic autoimmune conditions and improving patient quality of life.