Catapres

Generic name: clonidine (oral)
Drug class: Antiadrenergic agents, centrally acting

Medically reviewed by A Ras MD.

What is Catapres?

Catapres is a prescription medicine that is used to treat high blood pressure. Catapres may be given to you for other reasons.

Description

CATAPRES‑TTS® (clonidine) is a transdermal system providing continuous systemic delivery of clonidine for 7 days at an approximately constant rate. Clonidine is a centrally acting alpha‑agonist hypotensive agent. It is an imidazoline derivative with the chemical name 2, 6‑dichloro‑N‑2‑imidazolidinylidenebenzenamine and has the following chemical structure:

CATAPRES

System Structure and Components

CATAPRES‑TTS transdermal therapeutic system is a multi-layered film, 0.2 mm thick, containing clonidine as the active agent. The system areas are 3.5 cm2 (CATAPRES‑TTS‑1), 7.0 cm2 (CATAPRES‑TTS‑2) and 10.5 cm2 (CATAPRES‑TTS‑3) and the amount of drug released is directly proportional to the area (see RELEASE RATE CONCEPT). The composition per unit area is the same for all three doses.

Proceeding from the visible surface towards the surface attached to the skin, there are four consecutive layers: 1) a backing layer of pigmented polyester and aluminum film; 2) a drug reservoir of clonidine, mineral oil, polyisobutylene, and colloidal silicon dioxide; 3) a microporous polypropylene membrane that controls the rate of delivery of clonidine from the system to the skin surface; 4) an adhesive formulation of clonidine, mineral oil, polyisobutylene, and colloidal silicon dioxide. Prior to use, a protective slit release liner of polyester that covers the adhesive layer is removed.

Cross Section of the System:

Release Rate Concept

Catapres‑TTS® (clonidine) transdermal therapeutic system is programmed to release clonidine at an approximately constant rate for 7 days. The energy for drug release is derived from the concentration gradient existing between a saturated solution of drug in the system and the much lower concentration prevailing in the skin. Clonidine flows in the direction of the lower concentration at a constant rate, limited by the rate‑controlling membrane, so long as a saturated solution is maintained in the drug reservoir.

Following system application to intact skin, clonidine in the adhesive layer saturates the skin site below the system. Clonidine from the drug reservoir then begins to flow through the rate‑controlling membrane and the adhesive layer of the system into the systemic circulation via the capillaries beneath the skin. Therapeutic plasma clonidine levels are achieved 2 to 3 days after initial application of CATAPRES‑TTS transdermal therapeutic system.

The 3.5, 7.0, and 10.5 cm2 systems deliver 0.1, 0.2, and 0.3 mg of clonidine per day, respectively. To ensure constant release of drug for 7 days, the total drug content of the system is higher than the total amount of drug delivered. Application of a new system to a fresh skin site at weekly intervals continuously maintains therapeutic plasma concentrations of clonidine. If the CATAPRES‑TTS transdermal therapeutic system is removed and not replaced with a new system, therapeutic plasma clonidine levels will persist for about 8 hours and then decline slowly over several days. Over this time period, blood pressure returns gradually to pretreatment levels.

Before taking Catapres, tell your doctor:

If you are allergic to this medicine (Catapres); any part of this medicine (Catapres); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
If you are taking another drug that has the same drug in it.
If you are taking any of these drugs: Digoxin, diltiazem, verapamil, or a beta blocker like metoprolol or propranolol.

This is not a list of all drugs or health problems that interact with this medicine (Catapres).

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine (Catapres) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Catapres?

Tell all of your health care providers that you take this medicine (Catapres). This includes your doctors, nurses, pharmacists, and dentists.
Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine (Catapres) affects you.
To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
Check blood pressure and heart rate as the doctor has told you.
If you are taking this medicine (Catapres) and have high blood pressure, talk with your doctor before using OTC products that may raise blood pressure. These include cough or cold drugs, diet pills, stimulants, ibuprofen or like products, and some natural products or aids.
Be careful in hot weather or while being active. Drink lots of fluids to stop fluid loss.
Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
Talk with your doctor to find out what to do if you throw up after taking a dose of this medicine (Catapres).
If you are 65 or older, use this medicine (Catapres) with care. You could have more side effects.
Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

How is Catapres best taken?

Use this medicine (Catapres) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

Take with or without food.
Take this medicine (Catapres) at the same time of day.
Keep taking this medicine (Catapres) as you have been told by your doctor or other health care provider, even if you feel well.
Do not stop taking this medicine (Catapres) all of a sudden without calling your doctor. You may have a greater risk of side effects. If you need to stop this medicine (Catapres), you will want to slowly stop it as ordered by your doctor.

What do I do if I miss a dose?

Take a missed dose as soon as you think about it.
If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
Do not take 2 doses at the same time or extra doses.

What are the side effects of Catapres that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
Very bad dizziness or passing out.
Fast, slow, or abnormal heartbeat.
Change in how contact lenses feel in the eyes.

What are some other side effects of Catapres?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

Dry mouth.
Constipation.
Feeling dizzy, sleepy, tired, or weak.
Headache.
Upset stomach.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Catapres?

Store at room temperature in a dry place. Do not store in a bathroom.
Keep lid tightly closed.
Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.