Lascufloxacin is a quinolone antibacterial agent. Although it has a broad antibacterial spectrum, it is not suitable for everyone. Those allergic to quinolones and patients with myasthenia gravis require particular vigilance, and the risks should be fully assessed before medication. The following explains from three aspects.

I. Populations allergic to quinolones

1.Scope of contraindication

Those with a history of allergy to lascufloxacin or any quinolone drug (such as levofloxacin, moxifloxacin, etc.) are contraindicated for this product.

2.Risk of cross-allergy

Cross-allergy may exist among various quinolone varieties. Those who have experienced rash, pruritus, angioedema, or even anaphylactic shock with one variety should not try other varieties.

3.Common allergic manifestations

If rash, urticaria, facial or throat swelling, dyspnea, palpitations, etc. occur after medication, stop the drug immediately and seek medical attention.

4.Severe skin reactions

In very rare cases, severe skin reactions such as Stevens-Johnson syndrome and toxic epidermal necrolysis may occur. If large-area rash, blisters, or mucosal erosions appear, stop the drug immediately and seek emergency treatment.

5.Inform before medication

When seeing a doctor, proactively inform the doctor of past drug allergy history, especially whether quinolone drugs have been used and the reaction situation.

II. Patients with myasthenia gravis

1.Use with caution or contraindicated

Quinolones can aggravate muscle weakness symptoms, and patients with myasthenia gravis should avoid use; when use is truly necessary, weigh the benefits and risks and proceed under strict monitoring.

2.Aggravating mechanism

Such drugs may affect neuromuscular junction transmission, leading to aggravated muscle weakness, with ptosis, dysphagia, limb weakness, or even respiratory muscle paralysis.

3.High-risk signals

If new muscle weakness symptoms appear or original symptoms markedly worsen during medication, especially dyspnea and dysphagia, stop the drug immediately and seek emergency treatment.

4.Notes on concomitant medication

When used concomitantly with drugs that may affect muscle strength such as glucocorticoids, the risk of aggravation is higher, and monitoring should be strengthened.

III. Other populations requiring vigilance

1.Those at high risk of tendon lesions

Elderly patients, glucocorticoid users, organ transplant recipients, and those with a history of tendon disease have a higher risk of tendinitis or tendon rupture and should use with caution.

2.Patients with central nervous system diseases

Those with a history of epilepsy or psychiatric illness may have convulsions, insomnia, anxiety, or even psychiatric symptoms induced by quinolones, and should use with caution and be closely observed.

3.Those with QT interval prolongation

Those with QT interval prolongation, hypokalemia, or concomitant use of other QT-prolonging drugs should be alert to the risk of arrhythmia.

4.Children and pregnant women

Quinolones may affect cartilage development, and children and pregnant women generally should not use them unless the benefits outweigh the risks.