Theophylline
Severe
Textbook-cited
Theophylline toxicity (nausea, seizures, arrhythmias)
Monitor theophylline levels and reduce dose
Source: KDT 7e · p948
Drug reference
pefloxacin
Fluoroquinolone · Antibacterial
FluoroquinoloneAntibacterialATC null
CDSCO approved
EXCRETION
—
not curated
INTERACTIONS
2 major
SEVERE in our sources
PREGNANCY
X
FDA category + note
Top interactions
- TheophyllineSevereTextbook-citedKDT 7e · p948
- WarfarinSevereTextbook-citedKDT 7e · p948
Mechanism
null
Indications
meningeal infections (preferred due to greater CSF passage)many systemic infections
Dosing
- Adult
- 400 mg BD (oral, with meals); 400 mg (i.v., dilute in glucose solution, not saline)
- Hepatic adjustment
- Drugs to be avoided
Pharmacokinetics
Half-life
8–14 hr
Bioavailability
90–100%
Protein binding
20–30%
Metabolism
85% (partly to norfloxacin, which contributes to activity)
Excretion
accumulates on repeated dosing
Contraindications
- Liver disease
- gram-positive coccal and Listeria infections (less effective)
Pregnancy & lactation
Pregnancy
X
Drug interactions
Warfarin
Severe
Textbook-cited
Increased anticoagulant effect and bleeding risk
Monitor INR and reduce warfarin dose
Source: KDT 7e · p948
Related guidelines
Other Fluoroquinolone drugs
Ask House about pefloxacin
Continue into a citation-backed clinical answer with the drug context already attached.
Sources: KD Tripathi 7e·Verified: 2026-05-10 · House clinical team