Though not used as much today as it was in the past, Catapres (clonidine) remains an important treatment option for some patients with mild to moderate hypertension, especially if they haven't had good blood pressure control with other medicines.
While many high blood pressure medicines have some side effects involving the kidneys -- which may change blood flow to the kidney or affect how the kidney filters waste from the blood -- clonidine does not. This makes it especially useful for treating people who have high blood pressure along with some kind of kidney disease.
How Clonidine Works:
Clonidine belongs to a class of drugs called centrally acting alpha agonists. These drugs work by stimulating special receptors in the brain called alpha receptors. This causes a change in the body's hormone levels that leads to relaxation of the blood vessels, thus lowering blood pressure.
There is another class of anti-hypertension medicines called alpha blockers, but these drugs work on different types of alpha receptors in different locations within the body. Because clonidine can cause salt and water retention, it is usually given along with a diuretic.
Other Drugs Like Clonidine:
While clonidine is not the only drug of its kind, it is essentially the only one that patients are likely to encounter as a normal part of high blood pressure treatment. The only other drug in the same family as clonidine is alpha-methyldopa, which is only used in special circumstances and is typically only given in a hospital setting.
Clonidine, though, is still used in pill form outside of the hospital. In the United States, clonidine is sold under the brand name Catapres.
Clonidine Side Effects:
The most important side effect of clonidine is the potential suppression of some of the body's normal hormone systems. Because of this, it is important not to suddenly stop taking clonidine, even if you've only been using it for a few days. Clonidine use must be tapered off, in a series of decreasing doses over a period of time, to allow the body's normal hormone systems to power back up to normal levels.
Generally, clonidine causes few problems for most patients, but some side effects can include:
- Dry eyes or nose
- Dry mouth ("cotton mouth")
- "Rebound" hypertension when use is stopped suddenly
Notes About Clonidine:
Only you and your doctor can decide on a proper medication for treatment of high blood pressure. Be sure to notify your doctor if you are pregnant or breastfeeding, and to supply the names of any other medicines and/or supplements you are taking. Remember to include over-the-counter medicines, like aspirin or Advil (ibuprofen), and herbal/natural supplements.