Withdrawal
Patients should be instructed not to discontinue therapy without consulting their physician. Sudden cessation of clonidine treatment has, in some cases, resulted in symptoms such as nervousness, agitation, headache, and tremor accompanied or followed by a rapid rise in blood pressure and elevated catecholamine concentrations in the plasma. The likelihood of such reactions to discontinuation of clonidine therapy appears to be greater after administration of higher doses or continuation of concomitant beta-blocker treatment and special caution is therefore advised in these situations. Rare instances of hypertensive encephalopathy, cerebrovascular accidents and death have been reported after clonidine withdrawal. When discontinuing therapy with Catapres® (clonidine hydrochloride, USP) tablets, the physician should reduce the dose gradually over 2 to 4 days to avoid withdrawal symptomatology.
An excessive rise in blood pressure following discontinuation of Catapres tablets therapy can be reversed by administration of oral clonidine hydrochloride or by intravenous phentolamine. If therapy is to be discontinued in patients receiving a beta-blocker and clonidine concurrently, the beta-blocker should be withdrawn several days before the gradual discontinuation of Catapres tablets.
Because children commonly have gastrointestinal illnesses that lead to vomiting, they may be particularly susceptible to hypertensive episodes resulting from abrupt inability to take medication.
General
In patients who have developed localized contact sensitization to Catapres-TTS® (clonidine), continuation of Catapres-TTS or substitution of oral clonidine hydrochloride therapy may be associated with the development of a generalized skin rash.
In patients who develop an allergic reaction to Catapres-TTS, substitution of oral clonidine hydrochloride may also elicit an allergic reaction (including generalized rash, urticaria, or angioedema).
Catapres tablets should be used with caution in patients with severe coronary insufficiency, conduction disturbances, recent myocardial infarction, cerebrovascular disease or chronic renal failure.
Drug Interactions
Clonidine may potentiate the CNS-depressive effects of alcohol, barbiturates or other sedating drugs. If a patient receiving clonidine hydrochloride is also taking tricyclic antidepressants, the hypotensive effect of clonidine may be reduced, necessitating an increase in the clonidine dose.
Monitor heart rate in patients receiving clonidine concomitantly with agents known to affect sinus node function or AV nodal conduction, e.g., digitalis, calcium channel blockers and beta-blockers. Sinus bradycardia resulting in hospitalization and pacemaker insertion has been reported in association with the use of clonidine concomitantly with diltiazem or verapamil.
Serious side effects have been reported with Catapres including:
- Rash: Use of the Catapres patch may result in a rash, and a switch to Catapres tablets may or may not cause this side effect.
- Hypersensitivity (allergic) reaction: Use of the Catapres patch may result in a rash, and a switch to Catapres tablets may or may not cause this side effect. Tell your healthcare provider right away if you have some or all of the following symptoms…
- rash
- itchiness
- swelling of face or throat
- Skin burns: This side effect has been reported at the patch site in patients wearing the Catapres patch during a magnetic resonance imaging scan (MRI). It is recommended for the physician to have the patch removed before the patient has an MRI done.
Catapres can cause drowsiness or dizziness. Do not drive or operate heavy machinery until you know how Catapres affects you.
To avoid withdrawal side effects (e.g. nervousness, headaches, tremors), do not suddenly stop taking Catapres. Discuss with your doctor about slowly decreasing the dose before stopping use of this medication altogether.
Do not take Catapres if you:
- have a known hypersensitivity (allergic reaction) to clonidine or to any other component of the tablet or patch forms
Catapres (clonidine hydrochloride) is an oral medication used primarily for the treatment of high blood pressure. It is also used to treat severe menstrual cramps, hot flashes during menopause, Tourette’s syndrome, anxiety disorder, panic disorder, attention deficit hyperactivity disorder (ADHD), and alcohol and opiate (narcotic) withdrawal. It is in a class of medications called centrally acting alpha-agonist hypotensive agents, and works by decreasing the amount of blood the heart pumps out and by decreasing resistance in the blood vessels.
Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:
- alcohol
- barbiturates such as phenobarbital
- tricyclic antidepressants such as selegiline (Emsam, Eldepryl), amitriptyline (Elavil), or nortriptyline (Aventyl, Pamelor)
- antipsychotics such as haloperidol (Haldol), risperidone (Risperdal), and olanzapine (Zyprexa)
- digoxin (Lanoxin)
- calcium channel blockers such as verapamil (Calan), diltiazem (Cardizem), or amlodipine (Norvasc)
- beta blockers such as carvedilol (Coreg), metoprolol (Lopressor, Toprol XL), and atenolol (Tenormin)
This is not a complete list of Catapres drug interactions. Ask your doctor or pharmacist for more information.
Tell your doctor if you are breastfeeding or plan to breastfeed.
The active ingredient in Catapres is excreted in human breast milk. The effect of Catapres on the nursing infant is not known.
Before taking Catapres, tell your doctor about all of your medical conditions. Especially tell your doctor if you:
- if redness or swelling develops at patch site
- have a history of heart problems
- have hypertension due to pheochromocytoma (tumor of the adrenal glands)
- are planning to undergo surgery
- have kidney problems
- have liver problems
- wear contact lenses
- are pregnant or breastfeeding
Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.
Take Catapres exactly as prescribed.
Catapres comes as a tablet or a patch.
Catapres tablet is usually taken twice daily, once in the morning and once in the evening, with or without food.
The Catapres patch is applied to the skin once every 7 days. On Day 8, a new patch is applied, and the old patch should be removed. Apply the patch to a hairless area of intact skin (no burns, bruises, or cuts) on the upper outer arm or chest. Each new patch should be applied on a skin site different from the site of the old patch. If the patch loosens during 7-day wearing, the adhesive cover should be applied directly over the patch to ensure good adhesion.
To avoid withdrawal side effects (e.g. nervousness, headaches, tremors), do not suddenly stop taking Catapres. Discuss with your doctor about slowly decreasing the dose before stopping use of this medication altogether.
Discuss with your doctor about what to do if redness or swelling occurs at patch site.
If you miss a dose, take the missed dose as soon as you remember (tablet or patch). If it is almost time for the next dose (tablet), skip the missed dose and take your next dose at the regular time. Do not take two doses (tablet or patch) of Catapres at the same time.
Take Catapres exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.
Tablet: To start therapy, 0.1 mg tablet is given twice daily (morning and bedtime). Elderly patients may need to start from a lower dose. Further increments of 0.1 mg per day may be made at weekly intervals if necessary until the desired response is achieved. The typical dose range for Catapres tablet is 0.2 to 0.6 mg per day, divided into a morning and an evening dose. Maximum effective dose is 2.4 mg per day, but this dose amount is not commonly used.
Patch: To start therapy, Catapres patch dosage should be adjusted according to individual needs, starting with the lowest Catapres patch dose (0.1 mg). If after one or two weeks the desired reduction in blood pressure is not achieved, increase the dosage by adding another Catapres 0.1 mg patch or changing to a larger system (0.2 or 0.3 mg).
Catapres is a prescription medication used to treat hypertension.
This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.
Catapres is available in 0.1 mg, 0.2 mg, and 0.3 mg tablets and patches.
Active ingredient: clonidine
Inactive ingredients: vary by manufacturer
Clonidine stimulates alpha-adrenoreceptors in the brain stem. This action results in reduced sympathetic outflow from the central nervous system and in decreases in peripheral resistance, renal vascular resistance, heart rate, and blood pressure.
The patient’s blood pressure declines within 30 to 60 minutes after an oral dose, the maximum decrease occurring within 2 to 4 hours. Renal blood flow and glomerular filtration rate remain essentially unchanged. Normal postural reflexes are intact; therefore, orthostatic symptoms are mild and infrequent.
Most adverse effects are mild and tend to diminish with continued therapy. The most frequent (which appear to be dose-related) are dry mouth, occurring in about 40 of 100 patients; drowsiness, about 33 in 100; dizziness, about 16 in 100; constipation and sedation, each about 10 in 100.
The following less frequent adverse experiences have also been reported in patients receiving Catapres tablets, but in many cases patients were receiving concomitant medication and a causal relationship has not been established.
- Body as a Whole: Fatigue, fever, headache, pallor, weakness, and withdrawal syndrome. Also reported were a weakly positive Coombs’ test and increased sensitivity to alcohol.
- Cardiovascular: Bradycardia, congestive heart failure, electrocardiographic abnormalities (i.e., sinus node arrest, junctional bradycardia, high degree AV block and arrhythmias), orthostatic symptoms, palpitations, Raynaud’s phenomenon, syncope, and tachycardia. Cases of sinus bradycardia and atrioventricular block have been reported, both with and without the use of concomitant digitalis.
- Central Nervous System: Agitation, anxiety, delirium, delusional perception, hallucinations (including visual and auditory), insomnia, mental depression, nervousness, other behavioral changes, paresthesia, restlessness, sleep disorder, and vivid dreams or nightmares.
- Dermatological: Alopecia, angioneurotic edema, hives, pruritus, rash, and urticaria.
- Gastrointestinal: Abdominal pain, anorexia, constipation, hepatitis, malaise, mild transient abnormalities in liver function tests, nausea, parotitis, pseudo-obstruction (including colonic pseudo-obstruction), salivary gland pain, and vomiting.
- Genitourinary: Decreased sexual activity, difficulty in micturition, erectile dysfunction, loss of libido, nocturia, and urinary retention.
- Hematologic: Thrombocytopenia.
- Metabolic: Gynecomastia, transient elevation of blood glucose or serum creatine phosphokinase, and weight gain.
- Musculoskeletal: Leg cramps and muscle or joint pain.
- Oro-otolaryngeal: Dryness of the nasal mucosa.
- Ophthalmological: Accommodation disorder, blurred vision, burning of the eyes, decreased lacrimation, and dryness of eyes.
Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of Catapres, there are no specific foods that you must exclude from your diet when receiving Catapres.
Alcohol may intensify some of the side effects of this medication.
Large overdoses may result in reversible cardiac conduction defects or dysrhythmias, apnea, coma and seizures. Signs and symptoms of overdose generally occur within 30 minutes to two hours after exposure. As little as 0.1 mg of Catapres has produced signs of toxicity in children.
There is no specific antidote for Catapres overdosage. In case of an overdose seek medical attention immediately.
Tell your doctor if you are pregnant or plan to become pregnant.
The FDA categorizes medications based on safety for use during pregnancy. Five categories – A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.
Catapres falls into category C. No adequate studies have been done in pregnant women. Animal study results do not always equal that of human response. Catapres should be used during pregnancy only if clearly needed.
It is not known if Catapres will harm your unborn baby.
Catapres® (clonidine hydrochloride, USP) tablets are indicated in the treatment of hypertension. Catapres tablets may be employed alone or concomitantly with other antihypertensive agents.