Cenforce FM 100 mg, the exact formulation matters because “FM” can refer to a combination product. If it contains sildenafil 100 mg, a doctor may adjust the dose for several reasons: Side effects: 100 mg can cause more headache, flushing, indigestion, dizziness, or visual symptoms. Sildenafil dosing can be reduced to 50 or 25 mg based on tolerability. D DailyMed +1 Age or organ function: Older adults and people with severe kidney or liver impairment may need a lower starting dose because sildenafil can remain at higher levels in the body. D DailyMed Other medicines: Some medicines, including alpha-blockers and strong CYP3A4 inhibitors, can increase the effects or blood levels of sildenafil, making a lower dose appropriate. D DailyMed +1 Effectiveness: If a lower dose isn't sufficiently effective and is well tolerated, a clinician may increase it up to 100 mg. D DailyMed Don't take more than one sildenafil dose in 24 hours, and sildenafil must not be combined with nitrate medicines or “poppers.” D DailyMed If you tell me what exactly is written under “Cenforce FM 100 mg” on your package (the active ingredients), I can explain the dose adjustments for that specific product.