The active ingredient clonidine is used to treat high blood pressure. In addition, the drug is also used to dampen withdrawal symptoms in alcohol, drug or medication addiction. Taking it can cause numerous side effects – including fatigue, dry mouth, and headaches. We provide detailed information about the effects, side effects, and dosage of clonidine.
Effect of clonidine
Clonidine is primarily used in the treatment of high blood pressure (hypertension). The active ingredient ensures in the body that less adrenaline and noradrenaline are released. These two messenger substances ensure that blood pressure is driven up. If their concentration drops, the blood vessels relax and dilate, and the heart has to work less forcefully. All of this also causes blood pressure to drop.
In addition to high blood pressure, clonidine can also be used as a supportive measure during anesthesia and to combat withdrawal symptoms. For example, the drug helps dampen withdrawal symptoms after alcohol, drug, or opioid addiction.
Side effect of clonidine
A number of side effects may occur while taking clonidine. The most common side effects include fatigue, drowsiness, and dry mouth. Likewise, headache, constipation, nausea and vomiting, impotence, and slowing of the heartbeat may also be experienced. Occasionally, skin reactions and itching may also occur.
On the other hand, side effects such as dizziness, sleep disorders, depression, mood swings, sensory disturbances, confusion and hallucinations are rather rare. Weight gain due to water retention is also rare.
To avoid further side effects, clonidine should never be discontinued abruptly, but slowly step by step. Otherwise, the so-called rebound phenomenon can occur. This can result in an exaggerated counter-reaction of clonidine, causing a very rapid and sharp rise in blood pressure.
Dosage of clonidine
Clonidine can be taken orally as a capsule or tablet, as well as injected intravenously, intramuscularly, or subcutaneously. In addition, the active ingredient is available in various doses. In general, the dose should always be started as low as possible and then slowly increased as needed.
Unless otherwise recommended by the doctor, treatment is started with a dose of 0.075 milligrams. If necessary, the dose can then be increased further. However, dosage adjustments should not be made for approximately two to four weeks.
Contraindications: When should clonidine not be taken?
You should not take clonidine under certain circumstances. This is particularly the case if you are allergic to the active ingredient. In addition, clonidine is also contraindicated in the following conditions, or the patient requires careful medical monitoring:
- Depression
- Low blood pressure
- Renal dysfunction
- Cardiac arrhythmias (AV block)
- Fresh myocardial infarction
- Bradycardia with less than 50 beats per minute.
- Polyneuropathy
- Severe circulatory disorders
- Severe coronary artery disease
- Constipation
During pregnancy and lactation, the drug must not be taken. Children must also not be treated with clonidine.
Clonidine: drug interactions
If clonidine is taken at the same time as other medications, drug interactions may occur. Therefore, always inform your treating physician about which medications you take on a regular basis.
Interactions with the following medications are known, among others:
- Diuretics
- Hypnotics
- Neuroleptics
- Tricyclic antidepressants
- Vasodilators
In addition, the use of drugs such as beta-blockers, which also affect blood pressure, should be avoided. Otherwise, it can lead to cardiac arrhythmias as well as a slowing of the heartbeat. Also, be careful not to consume alcohol at the same time as the active ingredient, otherwise the effect of clonidine may be enhanced.