Milkweed Corneal Toxicity - An Overview

Introduction

Milkweed is a favorite among gardeners because it attracts butterflies. However, it must be handled with caution. Milkweed produces a milky white sap with a slight toxin; the bitter taste deters many animals and insects from eating its fragile leaves. Certain insects, such as Monarch butterfly larvae, resist toxins.

They may amass enough poison in their body to make them unappealing to predators by eating nearly entirely on milkweed plants. Toxic cardiac glycosides are found in all parts of the plant. They can induce nausea, diarrhea, weakness, and disorientation in small doses, as well as seizures, heart rhythm abnormalities, respiratory paralysis, and even death in high amounts. When handled, milkweed can irritate the skin and eyes.

What is Milkweed?

A group of perennial flowers of the Asclepias genus, named for their milky sap, are also called milkweed. The Asclepias genus has about 200 species endemic to Africa, North America, and South America. Monarch butterflies cannot survive without milkweed; their caterpillars consume only milkweed plants, and adult monarchs require milkweed to deposit their eggs.

The plant is distinguished by its unusual pod-like fruit, which contains tightly packed seeds. The seeds are released as the fruit pods develop and turn brown. Toxic cardiac glycosides are found in all sections of the plant. The plant's latex fluid has the most prominent cardiac glycosides, followed by the stems, leaves, and roots. The plant is most dangerous right before it matures.

Cardiac glycoside-containing plants have been utilized for medicinal purposes since ancient times. Indigenous peoples used milkweed to treat swelling, rashes, diarrhea, and respiratory problems. However, due to the limited therapeutic windows of cardiac glycosides, slight variations in dose might result in significant alterations in toxicity.

Exposure to milkweed plants is highly prevalent due to the plant's abundance. Even though milkweed is a deadly plant, several websites feature recipes for fried milkweed pods, shoots, and elixir. According to several sources, the cardiac glycosides found in milkweed are water-soluble, making it safe to eat if cooked correctly. However, there is no evidence to back this up. Even after being boiled or cooked, eating milkweed is not advised as it can be harmful.

What is Milkweed Corneal Toxicity?

• When dealing with some of our well-known, favorite plants, such as Milkweed, Asclepias sp., corneal endothelial toxicity, a toxicity that affects the innermost layer of the cornea and can produce symptoms such as light sensitivity, poor vision, and acute discomfort, is conceivable.

• Humans are not immune to this toxin. Milkweed sap is highly irritating to the skin but is also quite deadly if it goes into your eyes.

• This toxin has the potential to induce corneal endothelial toxicity.

• Corneal edema caused by plant extracts occurs not only in horticultural workers but also in home gardeners.

• The disorder produces mild vision impairment but is reversible and self-limiting. There is currently no documented therapy procedure for the care of this illness. Botanical toxin-induced corneal edema was self-limiting and cleared in a time-dependent pattern with no follow-up.

• Topical steroids did not appear to speed the resolution of corneal edema or affect the eventual outcome of this clinical disease.

• This toxicity affects the cornea's innermost layer, causing impaired vision, light sensitivity, and acute discomfort. Because these symptoms do not often appear promptly, most patients and physicians seldom identify it with milkweed toxicity.

• Unwary gardeners and children have been known to come into contact with the sap, known as latex, and suffer from severe side effects.

• Contact with ocular structures causes an inflammatory reaction and corneal edema. Carnenolides, cardiac glycosides similar to Digitalis, are produced by Milkweed plants and can bind to Sodium or Potassium ATPases (Na+/K+-ATPases).

• Direct ocular exposure can impede corneal pump activity, resulting in corneal edema and discomfort.

How Is Milkweed Corneal Toxicity Diagnosed?

• Milkweed corneal toxicity is diagnosed clinically.

• Patients, particularly youngsters, may or may not associate plant exposure with the development of symptoms.

• As a result, a high level of suspicion is required when taking a history and evaluating patients.

• Conjunctival infection, corneal edema, and Descemet folds characterize the clinical exam.

• The intraocular pressure is usually normal.

• Severe ocular toxicity symptoms such as perilimbal bleaching, anterior uveitis, and symblepharon are unusual.

• Endothelial toxicity can be diagnosed using specular microscopy and pachymetry.

How Is Milkweed Corneal Toxicity Managed?

1. As with any ocular chemical exposure, removing the offending material and stabilizing the anterior segment is critical.

2. Prompt eye irrigation with saline solution and visual pH monitoring are recommended.

3. In-vitro investigations have shown that topical Dexamethasone has a direct effect in that it can up-regulate the sodium or potassium activity in the corneal endothelium and speed up corneal recovery.

4. Concurrent administration of a hypertonic substance, such as five percent Sodium chloride, can reduce corneal edema through an osmotic action.

5. The patient should be thoroughly observed with daily examinations until clinically stabilized.

6. Fortunately, most patients recover within a few days with no lasting effects. The plant's sap can also cause skin and eye discomfort.

7. When touching milkweed sap, wash the afflicted area thoroughly with soap and water immediately.

8. If someone gets fluid in their eye and it causes pain, gently rinse the eye with room temperature water for 10 to 15 minutes.

9. Seek medical attention for any persistent skin or eye discomfort or symptoms.

10. The following methods can prevent it.

• Have a qualified professional identify all of the plants (both indoor and outdoor).

• Keep all plants away from youngsters and pets.

• Do not make homemade natural remedies.

• Prepare food or tea from plants only if experts understand how to do it safely.

Conclusion

Milkweed exposure is a severe clinical entity that produces significant ocular toxicity that eye doctors may adequately address with proper anterior segment stabilization and topical steroids or osmotic medications. To make this diagnosis, doctors must have a high level of suspicion and be careful to rule out more prevalent, vision-threatening etiologies.

Such eye toxicity can be avoided by wearing protective goggles and receiving health education. So, the next time you work in the garden, keep these eye-protection recommendations in mind: use eye protection, wear gloves, avoid rubbing the eyes or cleaning the eyebrows, and after handling, always wash your hands. Contacting an eye doctor if it appears to have milkweed toxicity is critical.