8-MOP Side Effects

Generic name: methoxsalen

Medically reviewed by Drugs.com. Last updated on Dec 5, 2024.

Note: This document provides detailed information about 8-MOP Side Effects associated with methoxsalen. Some dosage forms listed on this page may not apply specifically to the brand name 8-MOP.

Applies to methoxsalen: injection solution.

Other dosage forms:

• oral capsule liquid filled

Precautions

Eating certain foods while you are receiving methoxsalen (the active ingredient contained in 8-MOP) treatment may increase your skin's sensitivity to sunlight. To help prevent this, avoid eating limes, figs, parsley, parsnips, mustard, carrots, and celery while you are being treated with this medicine.

Your doctor should check your progress at regular visits to make sure this treatment is working and that it does not cause unwanted effects. You also should have regular eye examinations.

This medicine increases the sensitivity of your skin to sunlight and also may cause premature aging of the skin. Therefore, exposure to the sun, even through window glass or on a cloudy day, could cause a serious burn. If you must go out during the daylight hours:

• After each treatment, cover your skin with protective clothing for at least 24 hours. In addition, use a sun block product that has a skin protection factor (SPF) of at least 15 on those areas of your body that cannot be covered. If you have any questions about this, check with your health care professional.

For 24 hours after your methoxsalen treatment, your eyes should be protected during daylight hours with special wraparound sunglasses that totally block or absorb ultraviolet light (ordinary sunglasses are not adequate). This is to prevent cataracts. Your doctor will tell you what kind of sunglasses to use. These glasses should be worn even in indirect light, such as light coming through a window, or on a cloudy day.

Serious side effects of 8-MOP

Along with its needed effects, methoxsalen may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking methoxsalen:

Symptoms of overdose

• blistering and peeling of skin
• reddened, sore skin

Other side effects of 8-MOP

Some side effects of methoxsalen may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

• Reddening of skin, slight

Treatment with this medicine usually causes a slight reddening of your skin 24 to 48 hours after the treatment. This is an expected effect and is no cause for concern. However, check with your doctor right away if your skin becomes sore and red or blistered.

There is an increased risk of developing skin cancer after use of methoxsalen. You should check your body regularly and show your doctor any skin sores that do not heal, new skin growths, or skin growths that have changed in the way they look or feel.

Premature aging of the skin may occur as a result of prolonged methoxsalen therapy. This effect is permanent and is similar to what happens when a person sunbathes for long periods of time.

See also:

For healthcare professionals

Applies to methoxsalen: compounding powder, injectable solution, oral capsule.

General adverse events

The most common adverse event was nausea, which may be minimized or avoided by taking the medication with milk or food, or dividing the dose into 2 portions taken approximately 30 minutes apart.^[Ref]

Dermatologic

• Very common (10% or more): Pruritus (10%)
• Frequency not reported: Erythema, hypopigmentation, vesiculation and bullae formation, non-specific rash, herpes simplex, miliaria, urticaria, folliculitis, cutaneous tenderness, extension of psoriasis
• Postmarketing reports: Rash^[Ref]

Erythema:

Mild, transient erythema at 24 to 48 hours after PUVA therapy is expected and indicates a therapeutic reaction.

Any area showing moderate (grade 2 or higher) erythema should be shielded during subsequent UVA exposure until the erythema has resolved.

Grade 2 or higher erythema that appears within 24 hours after treatment may signal a potentially severe burn.

Erythema may progressively worsen over the next 24 hours, since peak erythemal reaction characteristically occurs 48 hours or later after methoxsalen ingestion.

Monitor the patient closely and protect from further UVA and sunlight exposures.

Differences between PUVA erythema and sunburn or UVB phototherapy:

The percent transmission through skin of UVS varies from 0 to 34%, where UVA varies from 1 to 80% (UVA is transmitted through a larger percentage of the skin)

PUVA induced DNA lesions may lead to a DNA crosslink, which is more lethal and psoralen-DNA photoproducts may be unfamiliar substrates for DNA repair enzymes.

DNA synthesis is suppressed longer after PUVA.

The time course of delayed erythema with PUVA is different and may not involve the usual mediators seen in sunburn; PUVA-induced redness may be just beginning at 24 hours (UVB erythema is past its peak by this time).

Histological alterations from PUVA show more dermal vessel damage and longer duration of epidermal and dermal abnormalities.^[Ref]

Pruritus can often be alleviated by frequent application of bland emollients or other topical agents.

Severe pruritus may require systemic treatment. If pruritus is unresponsive to these measures, shield pruritic areas from further UVA exposure until it resolves.

Discontinue treatment until pruritus resolution for intractable generalized pruritus.

Cardiovascular

• Common (1% to 10%): Hypotension
• Frequency not reported: Arrhythmia^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (10%)
• Common (1% to 10%): Vomiting
• Frequency not reported: Gastrointestinal disturbances
• Postmarketing reports: Dysgeusia^[Ref]

Immunologic

• Common (1% to 10%): Infection/catheter related infection/ sepsis
• Frequency not reported: Folliculitis^[Ref]

Psychiatric

• Frequency not reported: Nervousness, insomnia, depression^[Ref]

Hypersensitivity

• Postmarketing reports: Allergic reaction^[Ref]

Local

• Common (1% to 10%): Vascular access complication^[Ref]

Other

• Common (1% to 10%): Transient fever
• Frequency not reported: Edema, malaise
• Postmarketing reports: Pyrexia^[Ref]

Nervous system

• Frequency not reported: Dizziness, headache^[Ref]

Musculoskeletal

• Frequency not reported: Leg cramps^[Ref]

Further information

8-MOP side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer