brimonidine/timolol vs clonidine
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Side-by-side comparison of brimonidine/timolol and clonidine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
( 7.7 ) Tricyclic antidepressants may potentially blunt the hypotensive effect of systemic clonidine. 7.8 Tricyclic Antidepressants Tricyclic antidepressants have been reported to blunt the hypotensive effect of systemic clonidine.
Combigan
Catapres
Combigan eye drops contain two medicines that lower pressure in the eye. It is used to treat glaucoma or high pressure in the eye.
Clonidine (Catapres) is a medicine used to treat high blood pressure. It can be used alone or with other blood pressure medicines.
Combigan is used to lower high pressure in your eyes. This medicine is for people with glaucoma or ocular hypertension. It is for those who need more help than one medicine can provide. Combigan helps lower the pressure in your eye.
Clonidine is used to treat high blood pressure. High blood pressure can lead to heart disease, stroke, and kidney problems. This medicine helps to lower your blood pressure to a safer level.
Combigan has two drugs that work together to lower eye pressure. Brimonidine lowers fluid production in the eye and increases fluid drainage. Timolol reduces fluid production.
Clonidine works in the brain to lower blood pressure. It tells your blood vessels to relax and widen. This makes it easier for blood to flow through your body, which lowers blood pressure.
- • Allergic conjunctivitis (eye allergy)
- • Conjunctival folliculosis (bumps on the eye)
- • Conjunctival hyperemia (redness of the eye)
- • Eye itching
- • Eye burning
- • Dry mouth (occurs in about 40 out of 100 people)
- • Drowsiness (occurs in about 33 out of 100 people)
- • Dizziness (occurs in about 16 out of 100 people)
- • Constipation (occurs in about 10 out of 100 people)
- • Feeling sleepy or sedated (occurs in about 10 out of 100 people)
- The medicine is not working 2,756
- Allergic reaction 440
- Tiredness 240
- Eye pressure increased 224
- Feeling dizzy 183
- Pain 3,038
- Fatigue 2,925
- Nausea 2,920
- Headache 2,798
- Hypertension 2,595
Combigan contains timolol, which can cause serious heart and breathing problems. These problems can be more likely if you have asthma, COPD, or heart failure. Tell your doctor if you have any of these conditions.
If you suddenly stop taking clonidine, your blood pressure may increase. This can cause serious problems. Talk to your doctor before stopping this medicine.
Animal studies suggest possible risk to the fetus. Tell your doctor if you are pregnant or plan to become pregnant. Timolol can pass into breast milk, so talk to your doctor about breastfeeding while using Combigan.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if clonidine will harm your unborn baby. Talk to your doctor if you are breastfeeding.
Also Compare, Nearby Drugs
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How to Read This brimonidine/timolol vs clonidine Comparison
brimonidine/timolol is classified in the Alpha-2 Agonist / Beta-Blocker Combination drug class, while clonidine sits within the Central Alpha-2 Agonist class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, brimonidine/timolol has 3,843 submissions while clonidine has 14,276. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to both drugs work in a similar way to lower blood pressure. taking them together can cause an additive effect, which might make your blood pressure drop too low.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for brimonidine/timolol or clonidine.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.