Concerta contains methylphenidate hydrochloride, a stimulant medication used to treat ADHD. It comes in four strengths: 18 mg, 27 mg, 36 mg, and 54 mg. What makes Concerta different from other methylphenidate products is its extended-release design, which uses a specialized delivery system to release the medication gradually over roughly 12 hours.
The Active Ingredient
The only active ingredient in Concerta is methylphenidate hydrochloride. This is the same stimulant found in Ritalin and other ADHD medications, but Concerta packages it in an extended-release tablet that controls how quickly your body absorbs it. Methylphenidate works by blocking the reabsorption of two brain chemicals, dopamine and norepinephrine, back into nerve cells. This keeps more of these chemicals available in the spaces between neurons, which improves focus, attention, and impulse control.
Inactive Ingredients
Beyond methylphenidate itself, each Concerta tablet contains a long list of inactive ingredients that serve specific structural and functional roles. According to the FDA-approved label, these include: butylated hydroxytoluene, carnauba wax, cellulose acetate, hypromellose, lactose, phosphoric acid, poloxamer, polyethylene glycol, polyethylene oxides, povidone, propylene glycol, sodium chloride, stearic acid, succinic acid, synthetic iron oxides, titanium dioxide, and triacetin.
These aren’t random fillers. Many of them are essential to the tablet’s extended-release mechanism. Cellulose acetate forms the outer membrane that controls how water enters the tablet. Polyethylene oxides expand when they absorb water, creating the pressure that pushes the drug out. Sodium chloride helps draw water into the tablet through osmosis. Hypromellose acts as a binding agent. The synthetic iron oxides and titanium dioxide are responsible for the tablet’s color, which varies by dose strength. Lactose is worth noting if you have a lactose sensitivity, though the amount in each tablet is small.
How the Extended-Release System Works
Concerta uses a technology called OROS (Osmotic-controlled Release Oral delivery System), which is essentially a tiny drug pump disguised as a pill. The tablet has a hard outer shell made of cellulose acetate with a small laser-drilled hole in one end. When you swallow the tablet, an outer coating dissolves first to deliver an initial dose of methylphenidate. Then water from your digestive tract slowly seeps through the shell, causing internal compartments to swell. This swelling pushes methylphenidate out through the laser-drilled hole at a controlled rate throughout the day.
Because the tablet’s shell doesn’t dissolve, you may notice what looks like an intact pill in your stool. This is normal. It’s just the empty shell after the medication has been released. The tablet should always be swallowed whole. Crushing, chewing, or breaking it destroys the delivery mechanism and releases the full dose at once, which is dangerous.
How to Identify Each Dose
Each Concerta strength has a distinct color and imprint to help you identify it:
- 18 mg: Yellow tablet, imprinted with “alza 18”
- 27 mg: Gray tablet, imprinted with “alza 27”
- 36 mg: White tablet, imprinted with “alza 36”
- 54 mg: Brownish-red tablet, imprinted with “alza 54”
All four are capsule-shaped extended-release tablets. The “alza” imprint refers to ALZA Corporation, the company that developed the OROS delivery technology.
Important Safety Considerations
Because Concerta contains methylphenidate, it carries a boxed warning (the FDA’s most serious label warning) about the potential for abuse, misuse, and addiction. The risk increases when the drug is taken at higher doses or through methods it wasn’t designed for, such as crushing and snorting the tablets.
Concerta should not be taken by anyone with a known hypersensitivity to methylphenidate or any of the tablet’s inactive ingredients. It is also contraindicated if you are taking or have recently taken (within the past 14 days) a type of antidepressant called an MAOI, because the combination can cause a dangerous spike in blood pressure.
Stimulant medications including Concerta have been linked to the onset or worsening of motor and vocal tics, and can aggravate Tourette’s syndrome. There have also been reports of angle-closure glaucoma in people taking methylphenidate, so those with certain eye conditions should be aware of this risk. People with open-angle glaucoma or elevated eye pressure need close monitoring while on the medication.