Extended-release clonidine (Kapvay) is an alpha-2 agonist. It's a non-stimulant medication used to treat attention deficit-hyperactivity disorder (ADHD) in adults and children. Clonidine ER (Kapvay) is taken by mouth, typically twice per day. Some of the more common side effects include sleepiness and headache. This medication rarely causes insomnia (trouble sleeping), and isn't known to cause weight gain. Brand name Kapvay has been discontinued; clonidine ER (Kapvay) is only available as a generic medication.
Attention-deficit hyperactivity disorder (ADHD) in people ages 6 years and older
Clonidine ER (Kapvay) is an alpha-2 agonist. It's not exactly clear how clonidine ER (Kapvay) treats ADHD. But it's thought to work by binding (attaching) to alpha-2 receptors in the part of the brain that's involved in attention and focus.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
blistering, burning, crusting, dryness, or flaking of the skin
chest pain or discomfort
confusion as to time, place, or person
decreased urine output
dilated neck veins
drowsiness
fast, pounding, or irregular heartbeat or pulse
general feeling of discomfort or illness
holding false beliefs that cannot be changed by fact
hyperventilation
irregular breathing
irritability
itching, scaling, severe redness, soreness, or swelling of the skin
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
lightheadedness, dizziness, or fainting
mental depression
paleness or cold feeling in the fingertips and toes
pounding, slow heartbeat
problems in urination or increase in the amount of urine
raised red swellings on the skin, lips, tongue, or in the throat
restlessness
seeing or hearing things that are not there
shaking
shortness of breath
skin rash
swelling of the face, fingers, feet, or lower legs
tightness in the chest
tingling or pain in the fingers or toes when exposed to cold
trouble with sleeping
troubled breathing
unusual excitement, nervousness, or restlessness
unusual tiredness or weakness
vivid dreams or nightmares
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Dizziness (extreme) or faintness
feeling cold
pinpoint pupils of the eyes
unusual tiredness or weakness (extreme)
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Not a first-choice option for ADHD
Need to take twice daily
Can cause withdrawal symptoms if stopped suddenly
Take clonidine ER (Kapvay) with or without food. If it's hurting your stomach, taking it with food might help.
Swallow the tablets whole; never chew, crush, or break the tablet. This can cause the blood levels in the body to rise too quickly, which can raise your risk for side effects. Contact your prescriber if you're having trouble swallowing clonidine ER (Kapvay).
Clonidine ER (Kapvay) can make you sleepy and dizzy. Avoid driving or doing tasks that require attention until you know how this medication affects you. Also, don't drink alcohol because it can make sleepiness and dizziness worse.
To lower your risk for these heart-related side effects (e.g., low blood pressure, slow heart rate, heart rhythm problems), your prescriber will start you on clonidine ER (Kapvay) at a low dose and slowly raise it based on how well you're tolerating the medication.
Take clonidine ER (Kapvay) exactly as prescribed. Don't stop taking it because doing so can put you at risk of withdrawal or "rebound" effects. Examples include high blood pressure, headache, increased heart rate, nervousness, and chest tightness. Contact your prescriber if you're interested in stopping clonidine ER (Kapvay). They'll give you specific instructions on how to lower your dose safely until you can stop the medication.
Clonidine ER (Kapvay) can interact with many medications, such as tricyclic antidepressants (TCAs), blood pressure medications, and medications that make you sleepy. Make sure to tell your care team about all of the medications you're taking before and during treatment with clonidine ER (Kapvay) so they can help you check for serious interactions
There have been rare reports of low birth weight in babies born to mothers who used clonidine ER (Kapvay) while pregnant. If you're pregnant or planning on becoming pregnant, discuss the risks and benefits of taking clonidine ER (Kapvay) with your obstetrician-gynecologist (OB-GYN).
Talk to your prescriber or OB-GYN about using clonidine ER (Kapvay) while breastfeeding. The medication can get into breastmilk, which can cause side effects.
Clonidine ER (Kapvay) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: History of heart problems | Kidney failure | History of fainting | Dehydration | Taking other medications that lower blood pressure, slow heart rate, or cause heart rhythm problems
Because clonidine ER (Kapvay) works by lowering norepinephrine, it can lower your blood pressure and slow your heart rate. Depending on your other medical conditions, your prescriber might recommend you measure and record your blood pressure at home. If you experience signs of low blood pressure like dizziness or lightheadedness, talk to your prescriber right away. They might need to lower your dose. But, if you've been taking clonidine ER (Kapvay) for a long time and suddenly stop it, you can experience a "rebound" effect and get suddenly high blood pressure. Some other rebound symptoms include headache, fast heart rate, nausea, chest tightness, or feeling nervous or anxious. Try not to miss any doses and don't stop taking clonidine ER (Kapvay) without talking to your healthcare professional first. They will help you get off this medication slowly and safely.
Clonidine ER (Kapvay) can also cause heart rhythm problems, like heart block. Your prescriber might order an EKG regularly throughout treatment to test you for an abnormal heart rhythm. If you experience signs of heart rate or rhythm problems like chest discomfort or fainting, go to the hospital right away because you might need emergency treatment.
To lower your risk for these heart-related side effects, your prescriber will start you on clonidine ER (Kapvay) at a low dose and slowly raise it based on how well you're tolerating the medication.
Risk factors: Taking high doses of clonidine ER (Kapvay) | Age 65 years or older | Drinking alcohol | Taking other medications that can cause sleepiness
Clonidine ER (Kapvay) can cause extreme sleepiness and drowsiness, especially if you're taking higher doses. This can affect your ability to think, react, and focus. Your risk is higher if you're also taking other medications that can cause drowsiness, such as benzodiazepines, anxiety medications, muscle relaxants, and sleep medications. Make sure you know how this medication affects you before driving a car or doing activities that require your concentration. Talk to your healthcare team right away if you feel too sleepy from clonidine ER (Kapvay).
Let your healthcare team know if you've ever had a skin rash after using the clonidine patch. If so, you might also have an allergic reaction to clonidine ER (Kapvay). Depending on how serious your reaction was, they might ask you to consider other options.
Adults and children ages 6 years and older: The typical starting dose is 0.1 mg by mouth once daily at bedtime. Your prescriber will raise your dose slowly over time, depending on your symptoms. The maximum recommended dose is 0.2 mg by mouth twice daily.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to clonidine
Attention-deficit hyperactivity disorder (ADHD) in people ages 6 years and older
Attention-deficit hyperactivity disorder (ADHD)
Attention-deficit hyperactivity disorder (ADHD) in people 6 years and older
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