CyberKnife vs Standard Radiation Therapy: Sessions, Precision and Who Suits Which

The folder on the kitchen table has two pamphlets in it. One shows a white robotic arm curving over a patient who looks almost asleep; the other shows a calendar with five weekday boxes ticked, week after week. A man in his sixties, recently told about a small spot on his lung, reads them both twice and lands on the same question millions of people type into a search bar: cyberknife vs conventional radiation, and which one is right for me?

The comparison is real, but the pamphlets frame it badly. One is not the futuristic option and the other the tired one. They are two ways of using the same physical tool, ionizing radiation, to damage the DNA of cancer cells until those cells can no longer divide. What differs is how tightly the beams are aimed, how much is delivered in each visit, and how many visits there are.

Those differences turn out to matter enormously for some tumors and very little for others. Understanding why is the whole point of the pages that follow.

What does 'CyberKnife vs conventional radiation' actually compare?

Start with the name. CyberKnife is a trademark for one robotic radiosurgery system, not a type of medicine and not, despite the word, a knife. Nothing is cut. The machine is a compact linear accelerator (a device that generates high-energy X-rays) mounted on a robotic arm that can swing around a patient and aim from a very large number of angles. When people search ‘cyberknife vs conventional radiation’, what they are really comparing is two philosophies of delivering radiation: stereotactic radiosurgery, which concentrates a large amount of radiation into one to five sessions, and conventional fractionated radiotherapy, which spreads a smaller daily amount over many weeks.

That distinction matters more than the hardware. Several machines can deliver stereotactic treatment, including standard linear accelerators fitted with advanced imaging. So the honest version of the question is less ‘which brand’ and more ‘a few large treatments or many small ones, and does my tumor suit the first approach’. The Mayo Clinic describes stereotactic radiosurgery as a treatment that uses many precisely focused beams, so that each individual beam has little effect on the tissue it passes through while the point where they converge receives a strong, targeted effect.

My own view, after years of reading the evidence: precision is a means, not an end. A tightly focused beam is only an advantage when the target is small, well defined on imaging and stable enough to be hit reliably. For a tumor that is large, has blurry edges, or sits in tissue that needs the protection of daily small fractions, the slower conventional course is not the outdated option; it is the appropriate one. Keeping that in mind makes everything else in this comparison clearer.

How does standard radiation therapy work, session by session?

Conventional external beam radiation begins not with treatment but with a planning appointment, often called simulation. A CT scan is taken in the exact position you will lie in for treatment, small skin marks or tiny tattoos are placed, and a team of radiation oncologists (doctors who specialize in treating cancer with radiation), medical physicists and dosimetrists (specialists who calculate how the beams should be shaped) builds a plan over the following days.

Treatment itself is divided into fractions, a fraction being one day’s portion of the total course. The National Cancer Institute notes that most people have external beam radiation once a day, five days a week, Monday through Friday, with courses lasting roughly 2 to 10 weeks depending on the cancer. The NHS puts each session at around 10 to 30 minutes, most of which is spent positioning; the beam itself is on for only a few minutes.

Why stretch it out? Radiation damages the DNA of every cell it hits. Healthy cells are generally better at repairing that damage between sessions than cancer cells are, so a daily rhythm lets normal tissue recover overnight while cancer cells accumulate injury. Modern conventional treatment is far from crude: intensity-modulated radiation therapy (IMRT) shapes the beam’s strength across the field, and image-guided radiation therapy (IGRT) takes a quick scan before each session to check alignment. The beams are still aimed carefully, and the margin of healthy tissue around the target is deliberately included to cover microscopic cancer cells that no scan can see.

You feel nothing during delivery. Side effects build gradually across the weeks rather than arriving on day one, which is one of the most practical differences from the stereotactic approach described next.

How does robotic stereotactic radiosurgery work?

Stereotactic radiosurgery (SRS) means using three-dimensional coordinates to aim many narrow beams at a single point with very high accuracy. When the target is outside the brain, the same idea is usually called stereotactic body radiation therapy (SBRT). A robotic system is one way of delivering both.

The pathway starts the way any radiation course does: consultation, then detailed imaging with CT and often MRI or PET so the tumor’s edges can be traced slice by slice. For brain targets, a soft mesh mask is molded to your face to keep your head still; the Mayo Clinic notes that linear accelerator based systems can work frameless in this way, without the rigid pin-fixed head frame used by some other devices. For tumors in the lung, liver, prostate or pancreas, a clinician may place a few tiny metal markers called fiducials near the tumor beforehand, usually through a needle, so that the imaging cameras have something unmistakable to lock onto.

During treatment you lie on a table while the robotic arm moves around you in a choreographed sequence, pausing to deliver beams from many directions. Two ceiling-mounted X-ray cameras take frequent snapshots, compare them with the planning scan and let the robot nudge its aim if you have shifted. For lung or liver tumors that ride up and down with breathing, a chest sensor tracks the motion so the beam follows the target rather than chasing it.

Each session is longer than a conventional one. The Mayo Clinic describes stereotactic treatments lasting from less than an hour to a few hours, depending on how complex the plan is. You are awake, you can usually talk to staff through an intercom, and there is no anesthesia. Most people go home the same day.

How many CyberKnife treatments compared with a standard course?

This is the question people most want answered, and the numbers are genuinely different. According to the Mayo Clinic, stereotactic radiosurgery to the brain is often completed in a single session, while stereotactic body radiation therapy is typically delivered in one to five sessions. Set that against the National Cancer Institute’s description of conventional external beam radiation: five days a week for 2 to 10 weeks, which can mean anywhere from ten to fifty visits.

Fewer visits is an obvious practical win. Anyone who has driven a relative to daily appointments for six weeks understands that. But the biology behind the shorter schedule deserves a plain explanation, because it also explains the limits.

Giving a large amount of radiation in one sitting is far harder on whatever tissue receives it. The stereotactic approach is only tolerable because the beams converge so tightly that the surrounding tissue gets a fraction of what the target does. Widen the target, and the volume of healthy tissue receiving a high amount rises quickly. That is why a tumor the size of a grape may be a candidate and a tumor the size of a lemon in the same organ may not be.

Hypofractionation is the middle ground worth knowing about. It means fewer, larger fractions than a classic course but more than a stereotactic one, and it has become standard for some cancers, breast and prostate among them, on the strength of large trials. Your team may propose it without ever using the word ‘stereotactic’.

The takeaway: session count is a consequence of tumor size and location, not a measure of how powerful or how modern the treatment is. A five-session plan and a thirty-session plan can each be the right answer for different people.

What does 'precision' really mean, and does it always matter?

Marketing around robotic radiosurgery leans heavily on the word precision, so it is worth separating three things it can mean.

The first is mechanical accuracy: how reliably the machine points where it was told to point. Robotic systems and modern linear accelerators are both engineered to very tight tolerances here, and the frequent imaging during a stereotactic session is designed to catch and correct any drift in your position.

The second is dose fall-off: how sharply the radiation drops from a high amount inside the target to a low amount just outside it. Converging many narrow beams produces a steep edge, which is exactly what you want when a tumor sits beside the optic nerve, the brainstem or the spinal cord.

The third is the one no machine can solve: knowing where the cancer actually is. Imaging shows the visible tumor. It cannot show the scattered microscopic cells that some cancers send a few millimeters into surrounding tissue. Conventional planning deliberately draws a margin around the visible tumor to include that invisible spread. A stereotactic plan draws a much smaller margin because it assumes the target is compact and contained. If that assumption is wrong, sharper edges are not an advantage.

Movement is the final complication. A brain tumor inside a mask barely moves. A lung tumor can travel more than a centimeter with every breath, which is why tracking systems, breath-hold techniques or fiducial markers become part of the plan for body targets.

So does precision always matter? For a small, well-circumscribed target near something delicate, it is close to the whole story. For a cancer that needs a whole organ or a chain of lymph nodes treated, coverage matters more than a razor edge, and the conventional field is the precise choice in the sense that counts.

CyberKnife vs conventional radiation: a side-by-side table

The table below summarizes the practical differences. The figures for sessions and course length come from the Mayo Clinic and the National Cancer Institute descriptions cited in the references; everything else is a description of how the approaches are generally organized, not a promise about any individual plan.

Feature	Robotic stereotactic radiosurgery	Conventional fractionated radiation
Typical number of sessions	Often 1 for brain targets; usually 1–5 for body targets	Daily, five days a week, over about 2–10 weeks
Length of each session	Under an hour to a few hours	Roughly 10–30 minutes, mostly positioning
Amount delivered per session	Large	Small, accumulating over weeks
Target size best suited	Small, well defined on imaging	Any size, including whole organs or lymph node regions
Margin around visible tumor	Very narrow	Wider, to cover microscopic spread
Immobilization	Mesh mask or body cradle; sometimes fiducial markers	Skin marks or tattoos; masks for head and neck
Imaging during treatment	Frequent X-ray checks with automatic adjustment	Typically a scan before each session
Breathing motion	Can be tracked in real time	Managed with breath-hold or larger margins
Timing of side effects	Often mild and short-lived early; some late effects possible	Build gradually, often peaking near the end of the course
Usually combined with	Surgery, systemic therapy or observation, depending on case	Often chemotherapy or hormone therapy

Read across the rows and a pattern emerges. The stereotactic column trades breadth for sharpness and time for intensity. The conventional column does the opposite. Neither trade is inherently better; the right one is the one that fits the shape of the disease in front of the team.

Who is stereotactic radiosurgery usually for?

The clearest candidates share a profile: a target that is small, sharply outlined on imaging, limited in number and, ideally, sitting somewhere that surgery would be risky or unwanted.

In the brain, the Mayo Clinic lists a range of conditions treated with stereotactic radiosurgery, including cancers that have spread to the brain from elsewhere (brain metastases), benign tumors such as meningiomas, vestibular schwannomas (also called acoustic neuromas) and pituitary adenomas, tangles of abnormal blood vessels called arteriovenous malformations, and trigeminal neuralgia, a nerve condition that causes severe facial pain. In several of these, the tumor is not cancer at all; the goal is to stop growth or ease symptoms without opening the skull.

Outside the brain, stereotactic body radiation therapy is commonly considered for early-stage lung cancers in people who cannot safely have surgery or choose not to, for small liver tumors, for tumors of the spine, and increasingly for the prostate and pancreas. It is also central to a concept called oligometastatic disease, which simply means a cancer that has spread to only a few sites. Treating each of those few spots intensively is an active area of research, and it is the setting where many people first hear the word ‘stereotactic’.

Two practical factors also push a team toward the shorter course. One is the ability to hold still for a longer session; the mask and cradle help, but a person who cannot lie flat because of pain or breathing difficulty may struggle. The other is prior radiation to the same area, because a tight stereotactic field can sometimes retreat a region that has already received a full conventional course, where a second wide field would not be safe.

None of these is a guarantee of eligibility. They are the patterns that make a team pick up the phone to the physics department and ask whether a plan is feasible.

Who is usually steered toward standard radiation, or asked to wait?

Being told you are not a candidate for radiosurgery can feel like being denied the premium option. It rarely is. More often it means the disease has a shape that the conventional approach handles better.

Size is the first filter. As the target grows, the volume of healthy tissue that would receive a high amount in a one-to-five-session plan grows faster, and at some point the risk to that tissue outweighs the benefit of finishing quickly. Numbers matter too: a person with a great many brain metastases may be offered treatment to the whole brain rather than dozens of individual targets, and a cancer that has spread widely is generally treated with systemic therapy first.

Cancers that live in territory rather than in a lump are the second group. Breast cancer after lumpectomy, most head and neck cancers, many gastrointestinal cancers and lymphomas require treatment to the whole breast, the whole neck or an entire lymph node chain because microscopic disease may be anywhere in that region. A narrow beam cannot cover a region. These are also the cancers most often treated alongside chemotherapy, and the standard combinations were built around daily fractionation.

Tumors with indistinct edges on imaging, or those pressing directly on a structure that cannot tolerate a large single amount, fall into a gray zone where teams may deliberately choose more fractions to protect the neighbor.

Then there are the people asked to wait rather than switch. Common reasons include a recent operation whose wound needs to heal, a biopsy or staging scan still pending, active infection near the treatment site, pregnancy, or a plan to give drug therapy first and reassess. Waiting in these situations is not lost time; it is the team making sure the eventual plan is aimed at the right target.

CyberKnife side effects vs conventional radiation side effects

Both approaches share one reassuring fact: external beam radiation does not make you radioactive. The National Cancer Institute is explicit that you are safe to be around children and pregnant people between and after sessions. Beyond that, the side-effect profiles differ in timing more than in kind.

After brain radiosurgery, the Mayo Clinic describes fatigue, mild skin irritation or a small patch of hair loss where beams entered, headache and occasionally nausea in the first days, along with temporary swelling around the treated area that may briefly worsen symptoms before it settles. Body treatments carry effects specific to the neighborhood: a cough or chest-wall soreness after lung treatment, nausea after liver or pancreas treatment, urinary or bowel irritation after prostate treatment. Because the course is short, most early effects arrive and fade within days to a few weeks.

Conventional radiation tends to build. The NHS notes that tiredness, skin redness or soreness in the treated area, and site-specific effects such as a sore throat, diarrhea or bladder irritation usually develop over the course and may peak toward the end or shortly after it finishes, then improve over weeks. The daily rhythm gives the team a chance to watch, adjust and treat symptoms as they appear.

Late effects are the part of the conversation people most often miss. Months or years after either approach, radiation can leave scarring, changes in blood vessels or, after brain radiosurgery, a small area of damaged tissue called radiation necrosis that can mimic tumor regrowth on scans. Rib fracture after treatment near the chest wall and narrowing of small airways or bowel are among the rarer body-site examples. Your team will name the ones relevant to your location; the honest answer is that a shorter course does not mean a shorter list.

What do the following days and weeks usually look like?

After a stereotactic session, the first surprise for many people is how ordinary the rest of the day is. You walk out. The Mayo Clinic notes that most people can generally return to their usual activities within one to two days of stereotactic radiosurgery, and the commonest complaint that week is tiredness that responds to an early night. If a mask was used, your face may feel a little tender; if fiducial markers were placed for a body target, the needle site may be bruised.

Then comes the wait that catches people off guard. Radiation does not shrink tumors on the spot. Cells that have been fatally damaged still take weeks to die and be cleared away, so the first follow-up scan is typically scheduled months rather than days after treatment, and early scans can look confusingly unchanged or even slightly larger because of swelling. Your radiation oncologist will tell you when imaging becomes meaningful; resist the urge to read anything into a scan taken too soon.

A conventional course has a different texture. The NHS describes regular check-ins with the treatment team during the weeks of therapy, and the daily visits become a routine: parking, changing, twenty minutes on the table, home. Fatigue tends to deepen from around the midpoint, skin in the field may redden like sunburn, and the team will give specific washing and moisturizing instructions for the area. Effects often peak in the last week or the fortnight after, then begin to lift.

In both pathways, expect a conversation about what to watch for at home, a named contact number, and a follow-up appointment. Bring a written list of symptoms to that visit; small details about timing help the team tell a passing side effect from something that needs attention.

CyberKnife vs Gamma Knife and other stereotactic systems: what differs?

People comparing radiosurgery options quickly run into a second brand name. Gamma Knife is a trademark for a fixed device that uses roughly 200 small beams of gamma rays from cobalt sources, all converging on one point; the Mayo Clinic describes it as designed for targets in the brain and upper spine. Historically it has used a lightweight rigid frame attached to the skull for absolute stillness, although mask-based versions now exist.

A robotic linear accelerator system takes a different route to the same goal. Instead of hundreds of fixed sources firing at once, one X-ray source moves around you and delivers beams sequentially. It works with a mesh mask rather than pins, and because it is not built around the skull it can also treat targets in the lung, liver, spine, prostate and elsewhere, with breathing tracked in real time.

A third option is easy to overlook: many standard linear accelerators can now deliver stereotactic treatment when fitted with high-resolution imaging and fine beam-shaping devices. A hospital that does not own either branded machine may still offer stereotactic radiosurgery of comparable intent.

Proton therapy sits slightly apart. Protons are particles rather than X-rays and stop at a set depth in tissue, which can spare organs behind the target. It is typically fractionated rather than delivered in one to five sessions, so it is not a direct substitute in this comparison.

What does the evidence say about which device is superior? Very little, and honestly so. Major medical sources describe the systems as different tools for delivering the same treatment principle, and no large randomized trial has shown that the brand of machine, rather than the plan, the imaging and the team’s experience, determines outcomes. For a brain target that suits either device, the sensible question is not ‘which machine’ but ‘which does this team use most confidently for my kind of case’.

What people often get wrong about CyberKnife and standard radiation

Some misunderstandings surface in nearly every consultation. Correcting them early saves worry.

It is not surgery. The word ‘knife’ and the word ‘radiosurgery’ both suggest cutting. Nothing is incised, there is no anesthesia, and there is no wound to heal. The term reflects the goal, a sharp effect on a defined target, not the method.

Fewer sessions does not mean a stronger or better treatment. As explained above, the session count is set by what the surrounding tissue can tolerate, given the size and position of the target. A person offered thirty fractions is not receiving a weaker plan than a person offered three.

Precision does not mean no side effects. Tight beams reduce the amount reaching neighboring tissue, but the entry paths still pass through skin and organs, and the target itself sits inside a living structure that reacts to a large single amount. Late effects remain possible with either approach.

The tumor does not vanish on the day. Radiation starts a process that takes weeks to months to show on imaging. Early scans may look unchanged.

Conventional radiation is not outdated. Image guidance and intensity modulation have transformed it, and for cancers that occupy a region rather than a lump it remains the evidence-based standard.

You will not be radioactive. External beam treatment of either type leaves nothing behind in your body, and the National Cancer Institute confirms no restrictions on contact with others.

Not every tumor is eligible. A center owning a robotic system does not mean it will recommend one for you, and a team that declines is usually protecting healthy tissue, not withholding an upgrade.

Finally, no machine treats you alone. The quality of the imaging, the care taken tracing the target, and the physics checks behind the scenes shape results far more than the badge on the gantry.

Questions to ask your care team before choosing

A good consultation about cyberknife vs conventional radiation should leave you understanding why a particular approach fits your disease, not just what it is called. These questions tend to open that conversation.

• What is the goal of radiation in my case: to eliminate the visible tumor, to control its growth, to relieve a symptom, or to reduce the chance of recurrence after surgery?
• Why does the size, shape or location of my tumor make a stereotactic plan suitable, or unsuitable, for me?
• How many sessions are you proposing, how long will each take, and what determined that number?
• Will I need fiducial markers, a mask or a breathing-management technique, and what does placing them involve?
• What early side effects should I expect in the first two weeks, and which late effects are relevant to my treatment site?
• Is there a hypofractionated option in between the two approaches, and does the evidence for my cancer support it?
• How will this treatment fit with surgery, chemotherapy, hormone therapy or immunotherapy I am also having?
• Have I had radiation to this area before, and how does that change the plan?
• When will the first follow-up scan be, and how should I interpret changes on it?
• If this plan were not available here, what would the standard alternative be, and how do the two compare in the published evidence?
• Who do I call, day or night, if something worries me at home?

Write the answers down or bring someone who will. Ask for the name of the specific technique on your consent form; ‘stereotactic’, ‘hypofractionated’ and ‘conventional’ are terms you can then research in reliable sources. And if the plan differs from what a relative or a website led you to expect, ask the team to walk you through the reasoning. A clear explanation is part of good care, and every decision about which approach to use belongs with the clinicians who can see your scans.

When to call your doctor after CyberKnife or standard radiation

Most side effects of either approach are mild and expected, and your team will describe the ones specific to your treatment site. Some symptoms, though, should prompt a same-day call to the number you were given, or emergency services if they are sudden and severe.

After treatment to the brain or spine, call urgently for a new or rapidly worsening headache, especially with vomiting; a seizure; new weakness, numbness or clumsiness in a limb; sudden trouble speaking, seeing or understanding; confusion or unusual drowsiness; or loss of bladder or bowel control. Swelling around a treated area can cause some of these, and it is treatable, but it needs prompt assessment.

After treatment to the chest, call for shortness of breath that is new or worsening, chest pain, coughing up blood, or a fever. After treatment to the abdomen or pelvis, seek help for severe or persistent vomiting, black or bloody stools, blood in the urine, inability to pass urine, or severe pain that does not settle with the measures your team advised.

Whatever the site, a temperature of 38 degrees Celsius (100.4 degrees Fahrenheit) or higher deserves a call, particularly if you are also receiving chemotherapy. So does a skin reaction that blisters, weeps or shows spreading redness; redness, swelling or discharge at a fiducial marker insertion site; difficulty swallowing that stops you drinking; or any sudden calf pain, leg swelling or breathlessness, which can signal a blood clot.

Do not assume a symptom is ‘just radiation’ because it appeared after treatment. The team would far rather hear about a false alarm than miss something that needed attention. If you cannot reach them and the symptom is severe or sudden, go to the nearest emergency department or call emergency services.

Frequently asked questions

Stereotactic radiosurgery vs radiotherapy: what is the actual difference?

Stereotactic radiosurgery is a form of radiotherapy, not a separate treatment. Radiotherapy is the umbrella term for treating disease with ionizing radiation; the stereotactic version concentrates a large amount into one to five sessions using many converging beams and frequent imaging, while conventional radiotherapy spreads smaller daily fractions over several weeks. Both damage the DNA of cancer cells. The choice depends on the size, location and type of the target.

How many CyberKnife treatments do most people have?

According to the Mayo Clinic, stereotactic radiosurgery to the brain is often given in a single session, while stereotactic body treatments usually involve one to five sessions. The exact number is decided by the radiation oncology team based on how much healthy tissue surrounds the target and how well it tolerates a large amount at once. Fewer sessions is a consequence of the tumor’s shape, not a sign of a stronger treatment.

Is CyberKnife painful, and is it really surgery?

It is not surgery and the treatment itself is painless; you lie on a table while the machine moves around you, awake and without anesthesia. The word ‘radiosurgery’ describes the sharp, targeted effect, not cutting. Some people find the molded mask or lying still for an hour or more uncomfortable, and if fiducial markers are placed beforehand the needle site can be sore or bruised for a few days.

CyberKnife vs Gamma Knife: which is better for brain tumors?

No large trial has shown one machine to be superior; they are different tools for the same principle. Gamma Knife uses roughly 200 fixed cobalt beams converging on one point and is designed for the brain and upper spine, often with a frame. A robotic system moves a single X-ray source around a mask-immobilized head and can also treat body targets. Teams generally recommend the device they use most confidently for your kind of case.

What are the most common CyberKnife side effects?

The Mayo Clinic lists fatigue, mild skin irritation or a small patch of hair loss where beams enter, headache, nausea and temporary swelling around a treated brain area as common early effects. Body treatments carry site-specific effects such as cough after lung treatment or urinary irritation after prostate treatment. Late effects, including radiation necrosis in the brain or rib fracture near the chest wall, are less common but possible.

Why did my doctor recommend conventional radiation instead of CyberKnife?

Usually because your disease has a shape the conventional approach treats better. Larger tumors, cancers that need a whole organ or lymph node chain covered, tumors with indistinct edges, and treatments combined with chemotherapy generally suit daily fractions, which protect surrounding tissue and cover microscopic spread. The recommendation reflects your scans and cancer type, not the availability of equipment, and you can ask the team to explain the reasoning.

How soon after CyberKnife can I return to normal activities?

The Mayo Clinic notes that most people can generally resume usual activities within one to two days of stereotactic radiosurgery. Tiredness in the first week is common, and your team may advise avoiding driving on the day of treatment if you received medicine to help you relax. After a conventional course, fatigue often peaks toward the end and lifts gradually over the following weeks.

Does radiation therapy of either type make me radioactive?

No. External beam radiation, whether stereotactic or conventional, passes through the body and leaves nothing behind, so you are safe around children and pregnant people between and after sessions. The National Cancer Institute confirms there are no contact restrictions. Only internal radiation, such as implanted seeds or certain radioactive drugs, can involve temporary precautions, and those are different treatments from the ones compared here.

How long before a scan shows whether the radiation worked?

Usually months rather than days, because damaged cancer cells take weeks to die and be cleared, and early swelling can make a treated area look unchanged or slightly larger. Your radiation oncologist will schedule the first meaningful follow-up scan and explain what changes to expect. Reading too much into an early image is a common source of unnecessary worry, so ask when imaging becomes informative for your situation.

Can I have CyberKnife if I have already had radiation to the same area?

Sometimes, which is one of its recognized roles. Because a stereotactic plan delivers radiation to a very small volume with a steep fall-off at the edge, it can occasionally retreat an area that has already received a full conventional course, where a second wide field would not be safe. Eligibility depends on the earlier plan, the time since treatment and the structures nearby, and the decision rests with your team.

References

• NHS: Radiotherapy
• NHS: Radiotherapy side effects
• MedlinePlus: Radiation Therapy

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.