Common Side Effects

These side effects occur in more than 5% of patients and are usually mild to moderate:

🤕

Headache

Frequency: ~34% of patients

Usually mild and may improve with continued use

😴

Nausea

Frequency: ~11% of patients

Often reduces when taken with food

😰

Nervousness

Frequency: ~7% of patients

May include anxiety or restlessness

💊

Rhinitis

Frequency: ~7% of patients

Stuffy or runny nose

😵

Dizziness

Frequency: ~5% of patients

Usually mild and temporary

🍽️

Decreased Appetite

Frequency: ~5% of patients

May lead to weight loss if persistent

Serious Side Effects

These side effects are less common but require immediate medical attention:

🚨 Severe Skin Reactions

Stevens-Johnson Syndrome (SJS) / Toxic Epidermal Necrolysis (TEN)

  • Skin rash with blisters and peeling
  • Sores in mouth, throat, nose, eyes, or genitals
  • Fever and flu-like symptoms
  • Painful red or purple skin

Stop modafinil immediately and seek emergency care

⚠️ Psychiatric Symptoms

  • Depression or suicidal thoughts
  • Anxiety or panic attacks
  • Aggression or hostility
  • Hallucinations or delusions
  • Mania or hypomania

💓 Cardiovascular Effects

  • Chest pain or heart palpitations
  • Significant increase in blood pressure
  • Irregular heart rhythm
  • Shortness of breath

🤒 Allergic Reactions

  • Difficulty breathing or wheezing
  • Swelling of face, lips, tongue, or throat
  • Hives or widespread rash
  • Severe itching

Less Common Side Effects

These side effects occur in 1-5% of patients:

Gastrointestinal

  • Diarrhea
  • Dry mouth
  • Abdominal pain
  • Constipation

Neurological

  • Insomnia
  • Tremor
  • Confusion
  • Memory problems

Musculoskeletal

  • Back pain
  • Muscle stiffness
  • Joint pain

Other

  • Blurred vision
  • Elevated liver enzymes
  • Excessive sweating
  • Taste changes

Managing Side Effects

Headache Management

  • Stay well-hydrated
  • Take with food
  • Consider dose timing adjustment
  • Consult doctor about pain relievers

Nausea Prevention

  • Take modafinil with food
  • Avoid large meals before dosing
  • Stay hydrated
  • Consider ginger supplements (with doctor approval)

Sleep Issues

  • Take medication early in the day
  • Maintain consistent sleep schedule
  • Avoid caffeine in afternoon
  • Create relaxing bedtime routine

Appetite Changes

  • Eat smaller, frequent meals
  • Focus on nutrient-dense foods
  • Monitor weight regularly
  • Discuss with healthcare provider if significant