Patient leaflet - Clonidine Hydrochloride 100 micrograms/ 5 ml oral solution
1. What Clonidine hydrochloride is and what it is used for
Clonidine hydrochloride belongs to a group of medicines known as antihypertensives. Clonidine hydrochloride is used to lower high blood pressure (to treat hypertension).
You must talk to a doctor if you do not feel better or if you feel worse when taking this medicine.
2. What you need to know before you take Clonidine hydrochloride
Do not take Clonidine hydrochloride:
- If you are pregnant, likely to get pregnant or are breast feeding
- If you are allergic (hypersensitive) to clonidine or any of the other ingredients of this medicine (listed in section 6).
- This medicine should not be used by children and adolescents below 18 years of age
- If you have a slow heart rate due to heart problems
- If you are already taking other medicines that contain clonidine
Do not take this medicine if any of the above apply to you. If you are not sure, talk to your doctor or pharmacist before using Clonidine hydrochloride.
Warnings and precautions
- You have heart or kidney problems
- You have or have ever had depression
- You have constipation
Talk to your doctor, pharmacist or nurse before taking Clonidine hydrochloride if:
You have Raynaud’s disease (a problem with circulation to the
fingers and toes) or other blood circulation problems, including circulation to the brain
You have a nerve disorder that causes your hands and feet to
feel different (‘altered sensation’) or low blood pressure when you stand up.
If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before taking Clonidine hydrochloride.
Other medicines and Clonidine hydrochloride
Tell to your doctor or pharmacist if you are taking or have recently taken or might take any other medicines. This includes medicines that you buy without a prescription and herbal medicines. This is because Clonidine hydrochloride can affect the way some other medicines work. Also some other medicines can affect the way Clonidine hydrochloride works.
In particular, tell your doctor or pharmacist if you are taking any of the following medicines:
Other medicines that make you drowsy
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) such as ibuprofen
Medicines for depression such as imipramine or mirtazapine
- Beta blockers such as atenolol
Please also tell your doctor or pharmacist if you are taking any of the following medicines for high blood pressure or other heart problems:
- Water tablets (‘diuretics’) such as furosemide
Alpha blockers such as prazosin or doxazosin. These can also
be used for prostate problems in men
- Vasodilators such as diazoxide or sodium nitroprusside
Calcium antagonists such as verapamil or diltiazem
hydrochloride
- ACE inhibitors such as captopril or lisinopril
- Digitalis glycosides such as digoxin
If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before taking Clonidine hydrochloride.
Tests
If you are having any blood tests, tell the person giving the test that you are taking this medicine. This is because Clonidine hydrochloride can affect results relating to your liver.
Package leaflet: Information for the user
Clonidine hydrochloride 100 micrograms/ 5 ml Oral Solution
As you may get dry eyes whilst taking this medicine, this may be a problem if you wear contact lenses.
Children and adolescents
This medicine should not be used in children or adolescents under 18 years of age.
Instructions for the use of syringe:
- a)
Open the bottle: press the cap and turn it anticlockwise (figure 1). Separate the adaptor from the syringe (figure 2). Driving and using machines
You may feel drowsy, dizzy or could have some disturbances of vision. If affected, you should not drive, operate machinery or take part in any activities where these may put you or others at risk.
Clonidine hydrochloride contains:
Methyl parahydroxybenzoate (E218), which may cause allergic reactions (possibly delayed).
Sodium: This medicine contains less than 1mmol sodium (23 mg) per 5 ml, that is to say essentially ‘sodium-free’.
Clonidine hydrochloride with food and drink
You may feel drowsy while taking Clonidine hydrochloride. Drinking alcohol while taking Clonidine hydrochloride can make this worse.
3. How to take Clonidine hydrochloride
Always take Clonidine hydrochloride exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.
Your doctor will start you on a low dose and gradually increase it. This will depend on how well your medicine works to control your blood pressure
Route and method of administration
This medicine must be taken orally.
Use the measuring syringe provided in the pack to deliver the required dose.
Children and adolescents
This medicine is not recommended for use in children and adolescents below 18 years
- b) Insert the adaptor into the bottle neck (figure 3). Ensure it is properly fixed. Take the syringe and put it in the adaptor opening (figure 4).
- c) Turn the bottle upside down. Fill the syringe with a small amount of solution by pulling the piston down (figure 5A), then push the piston upwards in order to remove any possible bubble (figure 5B). Pull the piston down to the graduation mark corresponding to the quantity in millilitres (ml) prescribed by your doctor (figure 5C).
- d) Turn the bottle the right way up (figure 6A). Remove the syringe from the adaptor (figure 6B).
Taking this medicine
Operations
If you are going to have an operation, keep taking your Clonidine hydrochloride unless your doctor tells you otherwise. If you need to go into hospital, take the bottle of oral solution with you.
Pregnancy and breast-feeding
If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
Taking Clonidine hydrochloride is not recommended if you are pregnant, likely to get pregnant or breast-feeding.
- The usual starting dose is between 2.5 ml (50 micrograms) and 5 ml (100 micrograms) of oral solution, three times a day
- If necessary, your doctor will gradually increase the dose
Most people’s blood pressure is controlled by taking between 15 ml (300 micrograms) and 60 ml (1200 micrograms) of oral solution daily, in divided dosese
1 2
3 4
5 A 5 B 5 C
6 A 6 B
4. Possible side effects
Very common (affects more than 1 in 10 people)
- Depression, sleeping problems
- Headache
- Erectile dysfunction
- Your hands and feet feeling different (‘altered sensation’)
- Regular unusually slow heart beat
Raynaud’s phenomenon (a problem with circulation to the
fingers and toes)
- Itching, rash, urticaria (nettle rash)
- Dry eyes
- Irregular heartbeat
- Drying out of the lining of the nose
- Hair loss
- Increase in your blood sugar.
PIL/UK/MFG039/02/SMD/v1
If you take more Clonidine hydrochloride than you should
If you take more Clonidine hydrochloride than you should, talk to a doctor or go to a hospital straight away. Take the medicine pack with you, even if there is no medicine left.
If you forget to take Clonidine hydrochloride
If you forget a dose, take it as soon as you remember it. However, if it is nearly time for the next dose, skip the missed dose. Do not take a double dose to make up for a forgotten dose.
If you stop taking Clonidine hydrochloride
Do not stop taking Clonidine hydrochloride without first talking to your doctor. If you have been using this medicine for a long time, you may feel agitated when you stop taking it. This is called a ‘withdrawal effect’.
If you have any further questions on the use of Clonidine hydrochloride, ask your doctor or pharmacist.
Like all medicines, Clonidine hydrochloride can cause side effects, although not everybody gets them.
The side effects described below have been experienced by people taking Clonidine hydrochloride. They are listed as either very common, common, uncommon, rare or not known.
- Dizziness, feeling tired and more relaxed than usual (sedation)
Feeling dizzy when you stand up (because your blood
pressure has fallen sharply)
- Dry mouth.
Common (affects less than 1 in 10 people, more than 1 in 100 people)
Constipation, feeling sick (nausea), pain below the ear (from the salivary gland), being sick (vomiting)
Fatigue.
Uncommon (affects less than 1 in 100 people, more than 1 in 1,000 people)
Problems with understanding what is happening around you, hallucinations, nightmares
A feeling of discomfort and fatigue (‘malaise’).
Rare (affects less than 1 in 1,000 people, more than 1 in 10,000 people)
- Breast growth (‘gynaecomastia’) in men
Pseudo-obstruction of the large bowel, which causes colicky
pain, vomiting and constipation. Contact your doctor straight away if you have all these side effects.
Not known
Blurred vision
Confusion, loss of libido
Abnormally slow heart beat.
Reporting of side effects
If you get any side effects, talk to your doctor,pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme, Website: www.mhra.gov.uk/yellowcard, or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.
5. How to store Clonidine hydrochloride
- Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated
on the carton and label after ‘EXP’. The expiry date refers to the last day of that month.
- Discard 30 days after first opening.
- Do not refrigerate or freeze.
Do not use this medicine if you notice that the solution
becomes discoloured or shows any signs of deterioration. Seek the advice of your pharmacist.
If this leaflet is hard to see or read, please call +44 (0) 208 515 3700 for help.
This leaflet was last revised in 09/2025.
Marketing Authorisation Holder:
Syri Limited t/a SyriMed
Unit 4, Bradfield Road,
Ruislip, Middlesex,
HA4 0NU, UK.
What Clonidine hydrochloride looks like and contents of the pack
Clonidine hydrochloride is a clear colourless solution, supplied in an amber glass bottle, with a tamper evident, child resistant white plastic cap with a 10ml oral syringe with 0.25ml graduation mark for measuring and administering the dose and a syringe adaptor.
Clonidine hydrochloride is supplied in a bottle containing150ml oral solution.
6. Contents of the pack and other information
What Clonidine contains
The active substance is clonidine hydrochloride.
Each 5ml of oral solution contains 100micrograms of clonidine hydrochloride.
The other ingredients are: methyl parahydroxybenzoate (E218), sodium dihydrogen phosphate monohydrate (E339), disodium phosphate (E339), sucralose (E955) and purified water.
- e)
Empty the contents of the syringe into the patient’s mouth by
pushing the piston to the bottom of the syringe (figure 7). The contents of the syringe should be emptied into the side cheek of the patient's mouth to avoid a choking hazard. Close the bottle with the plastic screw cap. Wash the syringe with water (figure 8).
Two cases of hepatitis (inflammation of the liver) have also been reported. This might show up in some blood tests. Your body may hold onto more water than usual (fluid retention).
- Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.