[Posted 12/17/2013]ISSUE: FDA is warning that methylphenidate products, one type of stimulant drug used to treat attention deficit hyperactivity disorder (ADHD), may in rare instances cause prolonged and sometimes painful erections known as priapism. Based on a recent review of methylphenidate products, FDA updated drug labels and patient Medication Guides to include information about the rare but serious risk of priapism. If not treated right away, priapism can lead to permanent damage to the penis.
Priapism can occur in males of any age and happens when blood in the penis becomes trapped, leading to an abnormally long-lasting and sometimes painful erection. Another ADHD drug, Strattera (atomoxetine), has also been associated with priapism in children, teens, and adults.
Priapism appears to be more common in patients taking atomoxetine than in those taking methylphenidate products; however, because of limitations in available information, FDA does not know how often priapism occurs in patients taking either type of product.
See the FDA Drug Safety Communication for additional information, including a Data Summary
BACKGROUND: Methylphenidate products are central nervous system (CNS) stimulants used to treat attention deficit hyperactivity disorder (ADHD).
RECOMMENDATION: Healthcare professionals should talk to male patients and their caregivers to make sure they know the signs and symptoms of priapism and stress the need for immediate medical treatment should it occur. Younger males, especially those who have not yet reached puberty, may not recognize the problem or may be embarrassed to tell anyone if it occurs.
Encourage your patients to read the Medication Guide they receive with every filled prescription. Use caution when considering switching patients from methylphenidate to atomoxetine. Patients should not stop taking a methylphenidate product without first discussing it with your health care professional.
Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program.
For more information visit the FDA website at: Web Siteand Web Site.
Dexmethylphenidate can be habit-forming. Do not take a larger dose, take it more often, take it for a longer time, or take it in a different way than prescribed by your doctor. If you take too much dexmethylphenidate, you may find that the medication no longer controls your symptoms, you may feel a need to take large amounts of the medication, and you may experience unusual changes in your behavior Tell your doctor if you drink or have ever drunk large amounts of alcohol, use or have ever used street drugs, or have overused prescription medications.
Do not stop taking dexmethylphenidate without talking to your doctor, especially if you have overused the medication. Your doctor will probably decrease your dose gradually and monitor you carefully during this time. You may develop severe depression if you suddenly stop taking dexmethylphenidate after overusing it. Your doctor may need to monitor you carefully after you stop taking dexmethylphenidate, even if you have not overused the medication, because your symptoms may worsen when treatment is stopped.
Do not sell, give away, or let anyone else take your medication. Selling or giving away dexmethylphenidate is against the law and may harm others. Store dexmethylphenidate in a safe place where no one else can take it accidentally or on purpose. Keep track of how many tablets or capsules are left so you will know if any are missing.
Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with dexmethylphenidate and each time you get more medication. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website ( Web Site) or the manufacturer's website to obtain the Medication Guide.
WHY is this medicine prescribed?
Dexmethylphenidate is used as part of a treatment program to control symptoms of attention deficit hyperactivity disorder (ADHD; more difficulty focusing, controlling actions, and remaining still or quiet than other people who are the same age) in adults and children. Dexmethylphenidate is in a class of medications called central nervous system (CNS) stimulants. It works by increasing the amounts of certain natural substances in the brain.
HOW should this medicine be used?
Dexmethylphenidate comes as a tablet and an extended-release (long-acting) capsule to take by mouth. The tablet is usually taken twice a day, at least 4 hours apart, with or without food. The extended-release capsule is usually taken once a day in the morning. It may be taken with or without food, but will start to work faster if it is taken without food . Take dexmethylphenidate at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand.
Swallow the extended-release capsules whole; do not chew or crush them. If you are unable to swallow the extended-release capsule, you can carefully open the capsule and sprinkle the contents on a spoonful of applesauce. Swallow this mixture immediately, but do not chew it. Do not save this mixture to use at a later time.
Your doctor will probably start you on a low dose of dexmethylphenidate and gradually increase your dose, not more often than once a week.
Your condition should improve during your treatment. Call your doctor if your symptoms worsen at any time during your treatment or do not improve after one month.
Your doctor may tell you to stop taking dexmethylphenidate from time to time to see if the medication is still needed. Follow these directions carefully.
Are there OTHER USES for this medicine?
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What SPECIAL PRECAUTIONS should I follow?
Before taking dexmethylphenidate,
- tell your doctor and pharmacist if you are allergic to dexmethylphenidate, methylphenidate (Concerta, Metadate, Methylin, Ritalin), or any other medications.
- tell your doctor if you are taking monoamine oxidase (MAO) inhibitors, including isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate), or if you have stopped taking them during the past 14 days. Your doctor will probably tell you not to take dexmethylphenidate until at least 14 days have passed since you last took an MAO inhibitor.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin); antidepressants (mood elevators) such as amitriptyline (Elavil), amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Adapin, Sinequan), imipramine (Tofranil), nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil); clonidine (Catapres); decongestants (cough and cold medications); guanabenz; guanfacine; medications for high blood pressure; medications for seizures such as phenobarbital phenytoin (Dilantin), and primidone (Mysoline); methyldopa (Aldomet); selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft); and venlafaxine (Effexor). If you are taking the extended-release capsules, also tell your doctor if you are taking antacids or other medications for heartburn or ulcers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you or anyone in your family has or has ever had Tourette's syndrome (a condition characterized by the need to perform repeated motions or to repeat sounds or words), facial or motor tics (repeated uncontrollable movements), or verbal tics (repetition of sounds or words that is hard to control). Also tell your doctor if you have glaucoma, or feelings of anxiety, tension, or agitation. Your doctor will probably tell you not to take dexmethylphenidate.tell your doctor if anyone in your family has or has ever had an irregular heartbeat or has died suddenly. Also tell your doctor if you have recently had a heart attack and if you have or have ever had a heart defect, high blood pressure, an irregular heartbeat, heart or blood vessel disease, hardening of the arteries; or other heart problems. Your doctor will examine you to see if your heart and blood vessels are healthy. Your doctor will probably tell you not to take dexmethylphenidate if you have a heart condition or if there is a high risk that you may develop a heart condition.
- tell your doctor if you or anyone in your family has or has ever had depression, bipolar disorder (mood that changes from depressed to abnormally excited), or mania (frenzied, abnormally excited mood), or has thought about or attempted suicide. Also tell your doctor if you have or have ever had depression; mental illness; seizures;an abnormal electroencephalogram (EEG; a test that measures electrical activity in the brain); or thyroid disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking dexmethylphenidate, call your doctor.
- you should know that dexmethylphenidate should be used as part of a total treatment program for ADHD, which may include counseling and special education. Make sure to follow all of your doctor's and/or therapist's instructions.
What SPECIAL DIETARY instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do IF I FORGET to take a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What SIDE EFFECTS can this medicine cause?
Dexmethylphenidate may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain
- loss of appetite
- weight loss
- dry mouth
- difficulty falling asleep or staying asleep
- nervousness or jitteriness
Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:
- fast, pounding, or irregular heartbeat
- chest pain
- shortness of breath
- excessive tiredness
- slow or difficult speech
- dizziness or faintness
- weakness or numbness of an arm or leg
- changes in vision or blurred vision
- believing things that are not true
- feeling unusually suspicious of others
- aggressive behavior
- hallucinations (seeing things or hearing voices that do not exist)
- mood changes
- motor tics or verbal tics
- swelling of the face, throat, tongue, lips, or eyes
- purple blotches under the skin
- blistering or peeling skin
- joint pain
Dexmethylphenidate may cause sudden death in children and teenagers, especially children and teenagers with heart defects or serious heart problems. This medication also may cause sudden death, heart attack, or stroke in adults, especially adults with heart defects or serious heart problems. Talk to your doctor about the risks of taking this medication.
Dexmethylphenidate may slow children's growth or weight gain. Your child's doctor will watch his or her growth carefully. Talk to your child's doctor if you have concerns about your child's growth or weight gain while he or she is taking this medication. Talk to your child's doctor about the risks of giving dexmethylphenidate to your child.
Dexmethylphenidate may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at Web Site] or by phone [1-800-332-1088].
What should I know about STORAGE and DISPOSAL of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
What should I do in case of OVERDOSE?
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- uncontrollable shaking of a part of the body
- muscle twitching
- inappropriate happiness
- hallucinations (seeing things or hearing voices that do not exist)
- rapid, pounding, or irregular heartbeat
- widening of pupils (black circles in the middle of the eyes)
- dry mouth
What OTHER INFORMATION should I know?
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to dexmethylphenidate.
This prescription is not refillable. Be sure to schedule appointments with your doctor on a regular basis so you do not run out of medication.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: November 20, 2012.