Drug Description

Clonidine is a generic of Catapres and can be taken orally and as as a transdermal patch. The biological half-life of this drug is from 12 to 16 hours. This drug was approved by FDA.


Clonidine is used for the treatment of increased blood pressure by affecting some brain chemicals. When it happens, the blood vessels relax, thereby increasing the blood flow to the heart. This reduces the blood pressure in the patient. In addition, Clonidine can treat some other health problems, such as ADHD, kidney dysfunction, anxiety, headache, hot flushes and withdrawal symptoms.


Clonidine is available in the following dosages: 0.1 mg, 0.2 mg and 0.3 mg. Take the drug twice a day irrespective of the mealtime. You may take small dosage in the morning and a large one in the evening. Don’t take similar drugs at the same time. The extended-release pill must be swallowed whole. Various ingredients of this pill release at a different time. If you crush the pill, it would release all the components at the same time, which may cause the overdose. This drug can be taken separately or in combination with the other drugs. When the drug is taken for increased blood pressure, it must be taken even if the patient feels better.

Adverse effects

  • severe chest pain
  • nasal bleeding
  • severe head pain
  • irregular heartbeat
  • confusion
  • anxiety

Common adverse effects of Clonidine are lack of appetite, fatigue, vertigo, constipation, sleeplessness, dryness in the mouth and nightmares. The minor side effects may quickly disappear but if they persist, you should inform a doctor.


To achieve maximum benefit, you shouldn’t mix Clonidine with the drugs that interact with it, as drug interaction may either trigger certain adverse effects or change the drug mechanism. The medicines that may cause interaction are miorelaxants, sleeping drugs, medicines for anxiety disorder, narcotic pain relievers, etc. These drugs can be bought with or without prescription. Inform the doctors about any over-the-counter drugs or herbal supplements to exclude the possibility of drug interaction.