cholestyramine vs phenobarbital

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Side-by-side comparison of cholestyramine and phenobarbital. 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

Drug Interactions Cholestyramine resin may delay or reduce the absorption of concomitant oral medication such as phenylbutazone, warfarin, thiazide diuretics (acidic) or propranolol (basic), as well as tetracycline, penicillin G, phenobarbital, thyroid and thyroxine preparations, estrogens and progestins and digitalis.

Drug Class
cholestyramine Bile Acid Sequestrant
phenobarbital Anticonvulsant (Barbiturate)
Type
cholestyramine Prescription
phenobarbital Prescription
Summary
cholestyramine

Cholestyramine is a medicine that helps lower high cholesterol levels in your blood. It works by preventing your body from absorbing cholesterol in the intestines.

phenobarbital

Phenobarbital is a medicine that can help control seizures and calm you down. It belongs to a class of drugs called barbiturates.

What It Treats
cholestyramine

This medicine is used with a diet to lower high cholesterol, especially LDL cholesterol (the "bad" cholesterol). It may also help if you have high triglycerides, but it's not the best choice if high triglycerides are your main problem. Lowering cholesterol helps reduce your risk of heart disease.

phenobarbital

This medicine is used to treat generalized and partial seizures. Seizures are caused by unusual electrical activity in the brain. Phenobarbital helps to reduce this activity and prevent seizures.

How It Works
cholestyramine

Cholestyramine is a resin that binds to bile acids in your intestines. Bile acids help digest fats, including cholesterol. By binding to bile acids, cholestyramine prevents them from being reabsorbed, so your body uses cholesterol to make more bile acids, which lowers cholesterol levels in your blood.

phenobarbital

Phenobarbital works by slowing down the activity of your brain and nervous system. It increases the effects of a natural chemical in the body called GABA. This helps to reduce seizures and promote relaxation.

Common Side Effects
cholestyramine
  • Constipation
phenobarbital
  • Drowsiness
  • Sedation
  • Lethargy
  • Vertigo
FAERS Reports
cholestyramine
  • Diarrhoea 1,631
  • Fatigue 877
  • Nausea 783
  • Arthralgia 621
  • Headache 543
phenobarbital
  • Seizure 1,534
  • Drug Interaction 635
  • Toxicity To Various Agents 621
  • Status Epilepticus 482
  • Multiple-Drug Resistance 442
Serious Warnings
cholestyramine

Since cholestyramine can affect how your body absorbs other medicines, take other drugs at least 1 hour before or 4 to 6 hours after taking cholestyramine.

phenobarbital

You should not take this medicine if you are allergic to barbiturates. Also, do not take it if you have a history of porphyria, severe liver problems, or breathing problems.

Pregnancy
cholestyramine

Tell your doctor if you are pregnant or plan to become pregnant. Cholestyramine may affect how you absorb vitamins, so your doctor may recommend supplements. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.

phenobarbital

Tell your doctor if you are pregnant or plan to become pregnant. Phenobarbital can harm an unborn baby. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.

Also Compare, Nearby Drugs

Compare cholestyramine with

Compare phenobarbital with

How to Read This cholestyramine vs phenobarbital Comparison

cholestyramine is classified in the Bile Acid Sequestrant drug class, while phenobarbital sits within the Anticonvulsant (Barbiturate) 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, cholestyramine has 4,455 submissions while phenobarbital has 3,714. 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 cholestyramine can bind to phenobarbital in your intestines, which reduces how much of the medicine gets into your system. this can make the phenobarbital less effective.. 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 cholestyramine or phenobarbital.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.