Understanding Quillichew ER Side Effects

Quillichew ER (methylphenidate extended-release chewable tablets) is an effective ADHD medication, but like all medications, it can cause side effects. The good news is that most side effects are mild and often improve as your body adjusts. Knowing what to expect can help you feel more prepared and confident about treatment.

If you're new to this medication, you may want to start with our overview of what Quillichew ER is and how it's used.

Common Side Effects of Quillichew ER

These side effects are the most frequently reported. They're usually mild and may go away within the first few weeks of treatment:

• Decreased appetite — This is the most common side effect. Many patients notice they're simply not as hungry, especially during the day when the medication is active.
• Nausea — Some stomach upset is normal, particularly when first starting the medication
• Insomnia — Difficulty falling asleep can happen because Quillichew ER is a stimulant. Taking it in the morning helps minimize this.
• Headache — Mild headaches are common early in treatment
• Abdominal pain — Stomach discomfort or cramping may occur
• Vomiting — Less common than nausea but can happen
• Weight loss — Often related to decreased appetite over time
• Irritability — Some patients feel more easily frustrated, especially as the medication wears off
• Dizziness — Usually mild and temporary

Managing Common Side Effects

Appetite and Weight Loss

Decreased appetite is the side effect parents worry about most. Here are strategies that can help:

• Serve a big breakfast before the morning dose kicks in
• Offer calorie-dense snacks after school when the medication is wearing off
• Make dinner the largest meal of the day
• Track weight regularly and share the data with your doctor

Sleep Problems

If insomnia is an issue:

• Always take Quillichew ER in the morning
• Establish a consistent bedtime routine
• Avoid screens for at least an hour before bed
• Talk to your doctor if sleep problems persist — a dose adjustment may help

Irritability and Mood Changes

Some patients experience a "rebound" effect as the medication wears off in the evening. If irritability is significant, discuss it with your prescriber. Adjusting the dose or timing may help.

Serious Side Effects: When to Call Your Doctor

While rare, some side effects require medical attention. Contact your doctor if you notice:

• Increased blood pressure or heart rate — Your doctor should monitor these at regular checkups. If you notice a racing heart at rest, report it.
• Signs of circulation problems — Fingers or toes feeling numb, cold, or changing color (this could be Raynaud's phenomenon)
• Mood or behavior changes — New anxiety, agitation, hallucinations, or aggressive behavior
• Growth concerns — If your child isn't growing as expected, talk to your doctor. Long-term stimulant use can slow growth in some children.
• Prolonged or painful erection (priapism) — This is rare but requires immediate medical attention

When to Seek Emergency Help

Call 911 or go to the emergency room if you experience:

• Chest pain or shortness of breath
• Fainting or loss of consciousness
• Seizures
• Signs of a severe allergic reaction — rash, swelling of the face/tongue/throat, difficulty breathing
• Signs of a heart attack or stroke — sudden numbness, confusion, severe headache, or vision changes

Quillichew ER carries a boxed warning about the potential for abuse and dependence, as well as the risk of serious cardiovascular events. These risks are higher in people with pre-existing heart conditions, which is why your doctor screens for heart problems before prescribing.

Side Effects in Children vs. Adults

Quillichew ER is approved for patients aged 6 and older. Side effects can show up differently depending on age:

• Children tend to experience more appetite suppression, stomach pain, and growth effects
• Adults may notice more insomnia, dry mouth, and increased heart rate
• Both groups should be monitored for mood changes and cardiovascular effects

Special Warnings

Phenylalanine Content

Quillichew ER contains phenylalanine (3 mg per 20 mg tablet, 4.5 mg per 30 mg tablet, and 6 mg per 40 mg tablet). If you or your child has phenylketonuria (PKU), tell your doctor before starting this medication.

Drug Interactions and Side Effects

Some side effects can be worse if you're taking other medications at the same time. For example, combining Quillichew ER with certain antidepressants can increase the risk of side effects. Read our complete guide to Quillichew ER drug interactions to learn more.

How Long Do Side Effects Last?

Most common side effects improve within the first 1 to 4 weeks of treatment. If a side effect is bothersome and doesn't get better, your doctor may:

• Adjust the dose (Quillichew ER comes in 20 mg, 30 mg, and 40 mg tablets, and some can be split for finer dosing)
• Change the timing of the dose
• Switch to a different ADHD medication — see our guide to alternatives to Quillichew ER

Monitoring and Follow-Up

Your doctor should schedule regular follow-up appointments to monitor for side effects. Typical monitoring includes:

• Blood pressure and heart rate at each visit
• Height and weight for children (tracked on growth charts)
• Behavioral assessment to check that the medication is working
• Discussion of any new symptoms

If you're having trouble getting to follow-up appointments or finding a prescriber, our guide on finding a doctor who prescribes Quillichew ER can help.

Key Takeaways

• Most Quillichew ER side effects are mild — decreased appetite, insomnia, and headache are the most common
• Serious side effects like cardiovascular events are rare but require immediate attention
• Children should be monitored for growth and weight changes
• Side effects often improve in the first few weeks; talk to your doctor before stopping the medication
• If you're having trouble affording follow-up care, learn about savings programs for Quillichew ER