Biologic drugs treat some of the most serious conditions Americans live with — rheumatoid arthritis, Crohn’s disease, psoriasis, cancer, diabetes — and they’re responsible for more than half of all U.S. drug spending despite making up only 5% of prescriptions. Biosimilars were designed to change that math. Here’s what the research actually says about whether those savings reach patients, when they do, and when they don’t.
Most people searching this question have a specific medication in mind and a specific bill they’re trying to reduce. These are the honest answers to the questions that come up first.
- 1 Are biosimilars actually cheaper than the brand-name drug they replace? The list price of a biosimilar is almost always significantly lower than its brand-name reference biologic — typically 15% to 85% less depending on the drug and how much competition exists. When multiple biosimilars compete for the same drug class, prices fall faster. The FDA found that biosimilars on average carry about a 50% discount compared to the brand-name biologic. With Humira biosimilars, cash discounts at launch reached 85% off the $6,922 list price. But list prices are not what most insured patients pay — and the gap between list price savings and real patient savings is where things get complicated.
- 2 Will my insurance actually cover the biosimilar instead of the brand-name drug? It depends entirely on your specific insurance plan’s formulary — the list of drugs it covers and at what cost tier. Some plans actively push biosimilars onto lower-cost tiers and exclude or restrict the brand-name drug. Others do the opposite: they keep the brand-name drug in a preferred position because the manufacturer pays them rebates for that placement. A 2025 study found that 99% of Medicare Part D formularies covered at least one adalimumab biosimilar, but coverage tier placement — which determines what you pay at the counter — varied enormously. The only way to know where your plan stands is to look up your specific drug on your plan’s drug list at Medicare.gov or your insurer’s website.
- 3 Is a biosimilar as safe and effective as the original drug? Yes — an FDA-approved biosimilar has been rigorously evaluated and confirmed to have no clinically meaningful differences from the reference biologic in terms of safety, purity, and effectiveness. The FDA doesn’t approve a biosimilar as “close enough” — it has to demonstrate it is highly similar in structure and function with equivalent clinical results. “Interchangeable” biosimilars go a step further: they meet an even higher FDA standard and in most U.S. states can be substituted by a pharmacist without a new prescription from your doctor. As of mid-2026, 25 biosimilars carry the interchangeable designation.
- 4 How much have Medicare patients actually saved from biosimilars? Quite a bit — but primarily through Part B, which covers drugs administered in a doctor’s office or clinic, not drugs you pick up at a pharmacy. An HHS analysis found that biosimilar competition reduced Medicare Part B patient out-of-pocket costs by $3.2 billion between 2018 and 2023. In 2023 alone, the reduction was $1.1 billion — a 62% drop in out-of-pocket costs for affected patients. Patients using one of the biologics studied saved nearly $2,000 on average in annual out-of-pocket costs due to biosimilar competition. A separate JAMA Network Open study published in early 2026 found that mean annual out-of-pocket spending fell by about $94 in the four years after biosimilar competition began — a modest figure that reflects how insurance design can limit patient-level savings even when drug prices fall.
- 5 What’s the difference between a biosimilar and a generic drug? A generic drug is chemically identical to its brand-name version — same molecule, manufactured the same way. A biosimilar is different because it’s based on a biologic drug: a medication made from living cells rather than chemical synthesis. Because living manufacturing processes can’t produce a perfectly identical copy, biosimilars are “highly similar” rather than identical. They work the same way clinically, but the manufacturing complexity means they cost more to develop than generics and require a different approval pathway. This is also why biosimilars don’t automatically replace biologics at the pharmacy counter the way generics do for small-molecule drugs — interchangeability has to be specifically demonstrated and designated by the FDA.
- 6 Can my doctor switch me from my current biologic to a biosimilar without my consent? Your doctor cannot switch you to a biosimilar without your involvement — and for most biosimilars, a new prescription is required. Only biosimilars designated “interchangeable” by the FDA can be swapped at the pharmacy level without a new prescription, and even then, most states allow patients and physicians to refuse the substitution. If your insurance plan’s formulary change forces a switch — which happens increasingly as plans prefer biosimilars — you have the right to request an exception or prior authorization for the brand-name drug, though approval isn’t guaranteed. Talk to your prescribing physician before making any switch; real-world data shows most patients who switch to a biosimilar do well, but individual situations vary.
- 7 Why do some biosimilars barely save patients money even when the list price is much lower? The main reason is that insurance cost-sharing is often calculated as a percentage of the drug’s price — and if your plan places both the biologic and biosimilar on the same high tier, you may pay similar coinsurance rates on both. There’s also the rebate problem: brand-name biologic manufacturers pay pharmacy benefit managers (PBMs) substantial rebates to keep their drugs in preferred formulary positions. The PBM pockets the rebate; the patient doesn’t necessarily see the savings. This is a known, documented market distortion. The FDA, HHS, and Congress have all been working to address it — but as of mid-2026, it continues to limit how much biosimilar savings reach patients in practice.
Understanding why biosimilars exist — and why they’re not simply “generic biologics” — explains why the savings story is more complicated than it sounds.
Biologic drugs are made from living organisms — genetically modified cells, proteins, and complex molecules that cannot be produced through standard chemical synthesis. They are among the most effective treatments available for serious chronic diseases including rheumatoid arthritis, psoriasis, Crohn’s disease, ulcerative colitis, multiple sclerosis, macular degeneration, and certain cancers. The clinical impact can be dramatic. So can the price: a single biologic drug can cost $20,000 to $100,000 or more per year before insurance. Biologic medications account for only about 5% of U.S. prescriptions but consume more than 51% of total drug spending — a ratio that has made them the central target of drug cost reform efforts for over a decade.
A biosimilar is a biologic drug that has been independently manufactured to be highly similar to an already-approved biologic — called the reference product. Because the manufacturing involves living cells and complex biological processes, it is not possible to create an exact molecular copy. But “highly similar with no clinically meaningful differences” is the FDA’s standard — and biosimilars must prove they meet it through extensive analytical testing, clinical pharmacology studies, and often clinical trials. An FDA-approved biosimilar is not an approximation of the reference product — it is a confirmed equivalent in terms of safety, purity, potency, and effectiveness. The abbreviated approval pathway created by the Biologics Price Competition and Innovation Act of 2010 is specifically designed to allow competition without requiring manufacturers to repeat all of the original clinical trials that brought the reference drug to market.
The FDA grants a separate “interchangeable” designation to biosimilars that meet an even more rigorous standard — demonstrating that the biosimilar can be expected to produce the same clinical result as the reference product in any given patient, and that switching back and forth between the two carries no additional risk. Interchangeable biosimilars can be substituted at the pharmacy in most U.S. states without a new prescription from your doctor — bringing them closer to how generic drugs work for standard medications. As of mid-2026, 25 biosimilars carry the interchangeable designation, covering treatments for arthritis, psoriasis, diabetes, osteoporosis, macular degeneration, and inflammatory bowel disease. The FDA has been actively working to expand this pathway to accelerate patient access to lower-cost options.
The savings from biosimilars are real — but the numbers look different depending on whether you’re measuring list prices, what insurers pay, or what individual patients pay out of pocket. Here’s how to read the data honestly.
The clearest savings story is in Medicare Part B, which covers drugs given by infusion or injection in a clinic or doctor’s office. Because Medicare Part B reimbursement is tied to a drug’s Average Sales Price (ASP) — which falls as biosimilar competition drives prices down — patient cost-sharing also falls automatically. An HHS analysis covering 2018–2023 found that biosimilar competition cut Part B patient out-of-pocket costs by $3.2 billion over that period. In 2023 alone, the reduction was $1.1 billion — a 62% drop for the affected biologics. Patients treated with one of the studied biologics saved nearly $2,000 per year on average in reduced cost-sharing because of biosimilar competition. This is the setting where the savings mechanism works most directly and reliably.
For self-administered biologics picked up at a pharmacy — covered under Medicare Part D — the savings picture is more complicated. Insurance formulary placement, PBM rebate arrangements, and tier assignments all sit between the biosimilar’s lower list price and what a patient actually pays at the counter. A Health Affairs Scholar analysis of adalimumab (Humira) biosimilars found that when biosimilars were covered under Part D, they were almost always placed on tier 4 or higher — where patients pay coinsurance as a percentage of the drug price rather than a fixed copay. Only one biosimilar (Amjevita) was regularly placed on tier 3 with a fixed copay of $43–$45, making annual out-of-pocket cost about $540 — versus over $2,500 for brand-name Humira. That’s a real and significant saving — but it required the right formulary position to materialize. Without it, savings narrow considerably. The $2,000 Medicare Part D out-of-pocket cap introduced by the Inflation Reduction Act has also changed the calculation for heavy drug users, sometimes making the biologic and biosimilar cost roughly similar in practice.
Stepping back from individual patients, the system-wide savings from biosimilars are substantial. RAND Corporation estimated biosimilars would reduce direct biologic spending by $54 billion between 2017 and 2026 — roughly 3% of total biologic spending over that period. More recent IQVIA projections suggested biosimilars could reduce drug costs by $100 billion over a five-year period as more biologics lose patent protection and face competition. The faster biosimilars capture market share, the larger the savings — and market share has been accelerating. A Health Affairs study found that biosimilar market share exceeds the reference product around three years after the first biosimilar launches, and Average Sales Price drops about 30% as competition increases. In October 2025, the FDA announced new draft guidance specifically designed to reduce the clinical testing burden on biosimilar developers — a move intended to bring more biosimilars to market faster, which drives prices down further.
The FDA has approved biosimilars for a growing range of serious chronic conditions. These are the drug categories where patients are most likely to encounter biosimilar options and where the cost differences are most significant.
Humira (adalimumab) held the title of the world’s best-selling drug for years — and its biosimilars represent the most significant single price competition event in biologic drug history. More than 10 biosimilars have been FDA-approved for adalimumab, with seven designated interchangeable. Cash list prices range from roughly $550 to $3,744 per month depending on the biosimilar and formulation, compared to Humira’s list price of approximately $6,922 per month. Real-world 2025 data shows that most patients who switched to an adalimumab biosimilar maintained their clinical response — about 13% returned to the original Humira, underscoring the importance of monitoring after a switch. By mid-2026, most Medicare Part D formularies placed at least one adalimumab biosimilar on a lower cost tier than Humira itself.
Stelara (ustekinumab) cost the Medicare program $2.6 billion in 2023 — making it one of the highest-priority targets for biosimilar competition. Six ustekinumab biosimilars launched in 2025 at discounts reaching up to 90% below the brand-name list price of $13,836 per month. Medicare negotiated a Maximum Fair Price for Stelara of $4,695 under the Inflation Reduction Act — but the biosimilars launched at prices below even that negotiated rate. The first interchangeable Stelara biosimilar, Selarsdi, received full interchangeability approval in April 2025. Because ustekinumab biosimilar competition was so aggressive, the drug was removed from Medicare’s 2027 negotiation list — evidence that market competition outpaced government price-setting in this case.
Enbrel (etanercept) has had a notably more complex biosimilar story in the United States than in Europe, where biosimilars captured significant market share quickly. U.S. patent disputes delayed biosimilar competition for years. Enbrel’s Medicare Maximum Fair Price was set at $2,355 per month — a 67% reduction from its list price. Biosimilar golimumab (Simponi / Simponi Aria) for rheumatoid arthritis and ulcerative colitis received interchangeable biosimilar approvals in May 2026 under the brand names Immgolis and Immgolis Intri. The competitive landscape for TNF-inhibitor biologics is evolving rapidly in 2026 as multiple patents expire and additional biosimilars enter the market.
Insulin was one of the first biologic categories to face biosimilar competition in the U.S., and the results have been instructive about both the potential and the limits of market competition. Interchangeable insulin biosimilars — including Semglee and Rezvoglar for insulin glargine, and Langlara, approved in April 2026 — are priced at roughly 50% of the brand-name list price. However, unbranded insulin biosimilars priced at 50% of brand cost have captured less than 10% of the insulin market — evidence that lower list prices alone don’t automatically translate to patient access or prescriber adoption. The Inflation Reduction Act’s $35/month out-of-pocket cap for Medicare insulin purchases applies to many insulin products regardless of whether a patient is using the brand or biosimilar.
Denosumab is used to treat osteoporosis in postmenopausal women and bone-related complications in cancer patients — making it highly relevant to older adults and those undergoing cancer treatment. Eight denosumab biosimilars were approved in 2025 alone, and an additional interchangeable denosumab biosimilar, Ponlimsi, received FDA approval in March 2026. This level of competition for a single biologic is substantial and is expected to drive meaningful price reductions in the coming years as the biosimilars enter the market and gain formulary positions. For Medicare patients who currently pay 20% coinsurance on Prolia administered in their doctor’s office, a lower Average Sales Price translates directly to lower out-of-pocket costs.
Eye injection medications for macular degeneration — a leading cause of vision loss in older adults — are among the most frequently administered biologics in Medicare Part B. Lucentis (ranibizumab) and Eylea (aflibercept) both now have FDA-approved biosimilars, including interchangeable options for aflibercept (Opuviz and Yesafili). Because these drugs are administered in an ophthalmologist’s office, they fall under Medicare Part B — the setting where biosimilar competition most directly reduces patient cost-sharing. A biosimilar like Byooviz (ranibizumab) or Yesafili (aflibercept) works the same way clinically and can meaningfully reduce the 20% coinsurance a Medicare patient would otherwise pay on the brand-name drug’s price.
Cancer biologics are among the most expensive medications in existence, and biosimilars for several key cancer drugs have been approved and are gaining market share. Trastuzumab (Herceptin) biosimilars, bevacizumab (Avastin) biosimilars, and rituximab (Rituxan) biosimilars are all available for qualifying cancers. Bevacizumab and trastuzumab biosimilars reached nearly 60% volume share within two years of launch — significantly faster adoption than earlier biosimilars. For cancer patients, cost-sharing on these Part B drugs can reach thousands of dollars annually; biosimilar competition directly reduces those out-of-pocket amounts. An HHS analysis found that beneficiaries using Herceptin and its biosimilars had average annual out-of-pocket costs of $2,925 — but that biosimilar competition reduced those costs substantially relative to what they would have been without biosimilar entry.
This table covers the most widely used biologics with active biosimilar competition in the United States. Prices shown are approximate list prices — what you actually pay depends on insurance, formulary, and financial assistance programs.
| Brand / Generic Name | Condition(s) Treated | Brand List (monthly ~) | Biosimilar Cash Price ~ | Interchangeable? | Biosimilar Count | Part B or D? |
|---|---|---|---|---|---|---|
| Humira (adalimumab) | RA, psoriasis, Crohn’s, UC | ~$6,922 | From ~$550 | ✅ Yes (7) | 10+ | Part D |
| Stelara (ustekinumab) | Psoriasis, psoriatic arthritis, IBD | ~$13,836 | Up to 90% off | ✅ Yes | 6+ | Part B / D |
| Enbrel (etanercept) | RA, psoriatic arthritis, AS | ~$3,500+ | Medicare MFP: $2,355 | Limited | Few | Part D |
| Prolia / Xgeva (denosumab) | Osteoporosis, bone cancer | ~$1,000–$2,000 | Falling with competition | ✅ Yes (Ponlimsi) | 8+ approved ’25–26 | Part B |
| Lantus (insulin glargine) | Type 1 & Type 2 diabetes | ~$300–$400 | ~$100–$150 (unbranded) | ✅ Yes (Semglee, Rezvoglar, Langlara) | 3+ | Part D |
| Lucentis (ranibizumab) | Macular degeneration, DME | ~$1,900–$2,300 / dose | Lower via Part B ASP | Partial | 2+ | Part B |
| Eylea (aflibercept) | Macular degeneration, DME | ~$1,800–$2,200 / dose | Lower via Part B ASP | ✅ Yes (Opuviz, Yesafili) | 2+ | Part B |
| Herceptin (trastuzumab) | HER2+ breast & gastric cancer | Very high | ~60% volume share for biosimilars | Partial | Multiple | Part B |
| Avastin (bevacizumab) | Colorectal, lung, cervical cancer | Very high | ~60% volume share for biosimilars | Partial | Multiple | Part B |
| Rituxan (rituximab) | Lymphoma, CLL, RA | Very high | Biosimilars growing market share | Partial | Multiple | Part B |
List prices are approximate and fluctuate. Actual patient cost depends on insurance, formulary tier, income-based assistance, and whether the drug is covered under Part B or Part D. Always verify current pricing with your pharmacy, insurer, or the manufacturer’s patient assistance program.
Understanding why biosimilar savings sometimes don’t reach patients is just as important as knowing when they do — and it affects what you can do about it.
Brand-name biologic manufacturers pay pharmacy benefit managers (PBMs) — the companies that manage drug lists for insurers — large rebates in exchange for preferred formulary placement. This means a PBM may receive a $3,000 rebate for keeping a $9,000 brand-name biologic in the preferred tier while the biosimilar sits in a less favorable position. The PBM keeps the rebate; the patient doesn’t see it. This creates a situation where both the brand drug and the biosimilar may carry high coinsurance for patients, even though the biosimilar’s underlying price is much lower. The FTC, Congress, and the FDA have all acknowledged this as a market failure — multiple PBM settlements over rebate practices occurred in 2026 — but the problem has not been fully resolved. If your insurance plan’s biosimilar tier placement seems to make no financial sense, this is likely why.
Not all formulary positions are equal. A drug on Tier 1 has a fixed, low copay — often $5 to $50. A drug on Tier 4 or 5 typically requires coinsurance — you pay a percentage of the drug’s cost. On an expensive specialty biologic, even a 30% coinsurance rate on a biosimilar can still mean hundreds of dollars per month. The critical question is not just whether your plan covers a biosimilar, but what tier it’s on and whether it requires a copay or coinsurance. Look for biosimilar placement on Tier 3 or below, with fixed copays, for the best patient-level savings. A 2025 analysis found only one adalimumab biosimilar (Amjevita) was regularly placed on Tier 3 with affordable fixed copays — the others were on higher tiers even when covered.
Some physicians are cautious about biosimilars — either from habit, from patient requests to stay on a drug that is working, or from uncertainty about switching patients who are stable on a brand-name biologic. This is a legitimate clinical consideration in some cases. But it also means biosimilars don’t automatically reach patients even when they’re covered — the prescriber has to order them. If you are paying more than you’d like for a biologic medication, asking your doctor specifically whether a biosimilar is an appropriate option for your condition is a reasonable step. For new patients starting a biologic, starting on a biosimilar from the beginning avoids the switching question entirely.
The federal 340B drug pricing program allows safety-net hospitals and clinics to purchase drugs at steep discounts, then bill insurers at full price — pocketing the difference as revenue. Because biosimilars are cheaper, the spread between the discounted purchase price and the insurance reimbursement is smaller — meaning less revenue for the hospital. Hospitals participating in 340B have historically shown 66% less biosimilar adoption than other providers as a result, according to research cited in a recent Forbes analysis. Proposed reforms to the 340B program aim to address this distortion, but as of mid-2026, this remains a meaningful barrier to biosimilar uptake in hospital settings specifically — even when the biosimilar would clearly save the patient money.
The right path to lower costs looks different depending on whether you’re a Medicare patient, covered by employer insurance, or paying out of pocket.
First, find out whether your drug is administered in a clinic (Part B) or picked up at a pharmacy (Part D) — the path is different for each. For Part B drugs, ask your doctor whether a biosimilar is available and ask specifically if they would switch you to it — biosimilar competition directly reduces what you pay because Medicare coinsurance is calculated on the actual reimbursement rate. For Part D drugs, log into your Medicare plan’s website or call member services and ask what tier your current biologic is on, what tier the available biosimilar is on, and what you’d pay each month at a different tier. If the biosimilar is on a lower tier with a copay rather than coinsurance, switching could save hundreds of dollars a month. Also ask about Extra Help (the Low Income Subsidy) if your income and assets are modest — it can dramatically reduce drug costs regardless of biosimilar status.
Start by checking your plan’s drug formulary — usually on your insurer’s website or the back of your insurance card. Find out what tier your current drug is on and whether a biosimilar alternative is covered on a lower tier. If your plan covers a biosimilar on Tier 3 or below, switching to it (with your doctor’s agreement) may cut your costs substantially. If the biosimilar isn’t covered, or is on the same high tier as the brand, ask HR whether your employer offers a specialty drug advocacy or cost-management program. Many large employers are actively negotiating biosimilar access to reduce costs for both the company and employees. If you still can’t afford the drug, check the manufacturer’s patient assistance program — most biologic manufacturers offer copay cards or free drug programs for commercially insured patients who meet income thresholds.
Cash-pay patients have the most direct access to biosimilar pricing — and the savings can be dramatic. Interchangeable biosimilars like Cyltezo (adalimumab) have been available unbranded for cash-pay patients at approximately $550 per month through GoodRx and similar discount programs, compared to Humira’s $6,922 list price. For uninsured patients on biologics, a biosimilar with a prescription discount card can sometimes reduce costs by 80–90% compared to the brand. Use GoodRx, RxSaver, or the manufacturer’s unbranded pricing to compare options at pharmacies near you. Also investigate whether you qualify for a manufacturer patient assistance program (PAP) — many provide free or dramatically reduced-cost medication for patients below certain income thresholds regardless of insurance status.
Absolutely yes — and it’s one of the most practical questions you can ask before starting any biologic therapy. If a biosimilar exists for the drug being prescribed and it’s FDA-approved for your condition, asking whether you could start on the biosimilar instead of the brand avoids the switching question entirely. Starting on a biosimilar from day one means you never have the “should I switch from what’s working” dilemma later. Ask your doctor: “Is there an FDA-approved biosimilar for this drug that’s covered on a lower tier by my insurance?” If the answer is yes, starting there may save you significantly without any clinical compromise. Your doctor should be able to check your insurance formulary or have staff do so before your first prescription is written.
Formulary changes that require patients to switch from a brand biologic to a biosimilar are increasingly common. For the vast majority of patients, FDA-approved biosimilars work just as well — the FDA’s approval process is specifically designed to ensure this. Real-world 2025 and 2026 data on adalimumab biosimilar switches showed that most patients maintained their clinical response after switching. That said, a forced switch should always involve a conversation with your prescribing physician, not just a pharmacy notice. If your condition is stable on your current drug, your doctor needs to know about the formulary change. If you have clinical reasons for staying on the brand — such as a history of adverse reactions to other formulations — your doctor can request a formulary exception or prior authorization. That process isn’t guaranteed to work, but it’s worth pursuing if there’s a genuine clinical case to be made.
These are the specific things worth doing if you are paying too much for a biologic drug and want to know whether a biosimilar would actually help your situation.
The FDA’s Purple Book database lists every approved biologic and all approved biosimilars for it, including which ones are designated interchangeable. Go to fda.gov and search “Purple Book” — enter your brand-name drug and you’ll see all approved biosimilars, their interchangeability status, and their generic names. This is the definitive source for what’s actually been approved — more reliable than asking your pharmacy, which may only stock certain options.
Log in to your Medicare plan or commercial insurance website and search for both the brand-name drug and any biosimilars by their generic name. Look at the tier for each one. If the biosimilar is on Tier 1, 2, or 3 with a copay, calculate your monthly cost. If it’s on Tier 4 or 5 with coinsurance, calculate that too — it may be higher or lower than you expect depending on the drug’s actual price. The specific combination of tier placement and cost-sharing structure is what determines whether you actually save money — not just whether a biosimilar exists.
If a biosimilar is covered on a better tier, bring that information to your next appointment. Most physicians are willing to prescribe a biosimilar when the patient has confirmed insurance coverage and has a clear cost-saving reason. Ask specifically: “I checked and the biosimilar [name] is on Tier 2 with a $45 copay versus $800 coinsurance for the brand. Would you be comfortable prescribing the biosimilar?” A yes takes minutes. If your doctor wants to maintain the brand drug for clinical reasons, ask them to document those reasons for a potential insurance exception request.
Whether you end up on the biosimilar or stay on the brand, financial assistance programs exist for most biologic drugs. Brand manufacturers offer copay cards and patient assistance programs. Biosimilar manufacturers increasingly offer their own assistance. Non-profit organizations like the Patient Advocate Foundation and the HealthWell Foundation offer grants for specific conditions. If your out-of-pocket cost for any biologic exceeds $200 per month, it is worth 30 minutes to check whether assistance programs could reduce that — most patients don’t know these programs exist until they specifically look.
This page is for general informational purposes only and does not constitute medical, legal, or financial advice. Drug pricing, formulary placement, biosimilar approval status, and insurance coverage change frequently. Always verify current pricing and coverage with your pharmacist, prescribing physician, and insurance plan. FDA biosimilar approval status should be confirmed through the FDA Purple Book at fda.gov. Medicare coverage and cost-sharing should be verified through Medicare.gov or by calling 1-800-MEDICARE. Patient assistance program availability and eligibility requirements vary and should be confirmed directly with program administrators. The mention of specific drugs, biosimilars, or patient assistance programs does not constitute an endorsement. Consult your physician before making any changes to your medication regimen.