Drug Error Serotonin Syndrome Law Firm

What is Serotonin Syndrome?[1],[2]

Serotonin Syndrome can occur when you take a new medication that causes the level of the chemical called serotonin to build up in your body.

Serotonin Syndrome can also occur when you increase the dose of a medication or add another medication that further increases serotonin levels in your blood.

Serotonin works in your body by allowing your nerves and brain to send signals to help regulate things like digestion, mood and sleep, to name a few. Too much serotonin in your blood can cause your body to react irregularly which can lead to death in severe cases.

What causes Serotonin Syndrome?

Medications are able to control mood by increasing serotonin levels or when used in combination with other medications. These situations put patients at risk for serotonin syndrome. Some patients are sensitive, which makes them more susceptible to developing serotonin syndrome.

In normal conditions the nerve cells in the brain, spinal cord, and other parts of the body make serotonin to maintain a person’s attention span, behavior, mood, body temperature, blood flow, and digestion.

Certain medication combinations put patients at a higher risk of developing serotonin syndrome, such as antidepressant medications taken together with opioid or opioid-like pain medications and with certain types of antibiotics.

Monoamine oxidase inhibitors (MAOIs) antidepressants come with a special warning, to not take certain medications such as:

  • Marplan (isocarboxazid),
  • Nardil (phenelzine),
  • Zyvox (linezolid),
  • Azilect (rasagiline),
  • Emsam/Eldepryl/Zelapar (selegiline), or
  • Parnate (tranylcypromine)

Some over-the-counter medications taken in combination with prescription medications can increase serotonin levels can put patients at risk for serotonin syndrome. 

Medications associated with serotonin syndrome, Brand (generic) 

Selective Serotonin Reuptake Inhibitors (SSRIs) – These are antidepressants:

  • Celexa (citalopram)
  • Lexapro/Cipralex (escitalopram)
  • Paxil/Seroxat (Paroxetine)
  • Prozac (fluoxetine)
  • Luvox (fluvoxamine)
  • Zoloft/Lustral (Sertraline)

Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs):

  • Oleptro (trazodone)
  • Cymbalta (duloxetine)
  • Effexor (venlafaxine)

Other types of Antidepressants:

  • Wellbutrin/Zyban (Bupropion) – an antidepressant used to help people to stop tobacco-addiction

Tricyclic Antidepressants (also known as TCA antidepressants):

  • Elavil (amitriptyline)
  • Pamelor (nortriptyline)

Monoamine Oxidase Inhibitors (MAOIs) antidepressants:

  • Marplan (isocarboxazid)
  • Nardil (phenelzine) 

Prescription Migraine medications: 

Triptan Migraine Medications:

  • Axert (almotriptan)
  • Amerge (naratriptan)
  • Imitrex (sumatriptan)
  • Zomig (zolmitriptan)
  • Frova (frovatriptan)
  • Maxalt (rizatriptan)
  • Relpax (eletriptan)

Anti-Seizure Medications used for Migraines:

  • Tegretol (carbamazepine)
  • Depakene (valproic acid) 

Pain Medications:

Opioid pain medications: 

  • Tylenol #3 and Tylenol # 4 (acetaminophen with codeine)
  • Duragesic (fentanyl)
  • Demerol (hydrocodone meperidine)
  • Oxycontin/Percocet/Percodan (oxycodone)
  • ConZip/Ultram/Ultracet (tramadol)

Mood Stabilizer used to treat Pain:

  • Lithobid (lithium) 

Over-The-Counter Herbal Supplements:

  • John’s wort
  • Ginseng
  • Nutmeg 

Over-The-Counter Cough and Cold medications containing dextromethorphan:

  • Delsym (dextromethorphan)
  • Other medications containing dextromethorphan (there too many to list here, there are over 100 brands of cough and cold medications containing dextromethorphan sold over the counter) 

Prescription Anti-Nausea medication:

  • Sancuso/Granisol (granisetron)
  • Reglan (metoclopramide)
  • Inapsine(droperidol)
  • Zofran(ondansetron) 


  • Zyvox (Linezolid)

Anti-retroviral HIV/AIDS medications

  • Ritonavir(norvir)

What are the signs & symptoms of Serotonin Syndrome?

Patients develop:

  • a rapid heartbeat,
  • high blood pressure,
  • involuntary muscle spasms,
  • muscle stiffness,
  • restless behavior,
  • headache,
  • brain fog, and
  • extreme temperature sensitivity.

Severe cases typically present with:

  • seizures,
  • fever and

When Do Serotonin Symptoms appear?

The symptoms of serotonin syndrome can appear within hours of taking the new medication or increasing a dose of a medication you have been taking regularly. These early signs can include restlessness, confusion, heart beating fast, muscle spasms or loss of muscle control such as twitching/stiffening of muscles, excessive sweating, headache, diarrhea, shivering not related to cold temperatures and goose bumps.

What should I do if I get Serotonin Syndrome Symptoms?

Patients who experience these symptoms should call their doctor immediately. Their doctor may recommend they go to the closest emergency room.

Symptoms when serotonin syndrome are often severe and life threating. They include things such as irregular heartbeats, seizures and muscle spasms, high fever and loss of consciousness. Severe cases of serotonin syndrome required immediate medical care in a hospital.

How is Serotonin Syndrome diagnosed?

Serotonin syndrome can be hard to recognize because many of the symptoms can look like many other conditions. Physicians typically diagnose serotonin syndrome by a rule-out process, based on medical history and many general laboratory tests. Different X-ray scans may be ordered to rule out infections or determine which parts of the body are injured by serotonin syndrome.

How is Serotonin Syndrome treated?

Serotonin syndrome typically does not result in death if treatment is given until serotonin levels return to normal.

Unconsciousness and death can result from serotonin syndrome if patients do not get treatment in time. Treatment of serotonin syndrome is based on symptoms and severity.

If a patient has minor symptoms of serotonin syndrome, the medication causing it will be stopped. Typically, milder forms of Serotonin Syndrome can last anywhere from 24-72 hours after removing the medication causing serotonin syndrome and or taking medications to block serotonin in circulating in the blood. Serotonin syndrome associated with some types of antidepressants can last longer for several weeks because antidepressants stay in your body longer.

If the symptoms appear to be a cause for concern, the physician may admit the patient into the hospital to monitor until the symptoms subside.

In severe cases, the patient will be admitted to the hospital and receive treatment. Treatments may include:

  • muscle relaxants,
  • medications that block the body from making more serotonin,
  • oxygen,
  • medications to control how the heart beats,
  • blood pressure medications and
  • breathing tubes.

Whom Should I call?

Especially for death cases, or when the medical bills exceed $250,000.00, you will want to contact the law offices of Hamilton and Associates for an evaluation of the merits of your claim. Death and high bill cases are difficult; you will want a lawyer experienced in your specific type of case to evaluate your case so that your decision can be accurate. Call our office today at 816-540-4040.

Video Resources

Legal FAQs and Issues

This question has two parts. The solutions to these two problems drive law students and inexperienced lawyers crazy. In reality, it’s nearly always a straightforward legal analysis. The technical names of these legal problems are “choice of laws” and “venue.”   This is what court judges use to decide which laws should apply to your case and where your case should be held.

Typically, what laws will apply to your case will be decided by the actual physical place where the bad act occurred. For example, if a doctor prescribed an antibiotic to you knowing that you were allergic to it, and caused a close relative to die from end stage renal failure, the actual place where the mistake prescription was written would be the “location.” The laws of that location would apply.

Typically, the law of the location of the misconduct and the venue are the same. Venue, in ordinary terms, is the location of the court where your court case will be held. Venue is decided with a slightly different test than Choice of Laws. Venue is normally decided by being the place where the actual harm occurred. This is nearly always the same place as the bad act (Choice of Laws), but because of some delays or other actions, “Venue” and “Choice Laws” can be different. For example, if the harm resulted from a telephone call or internet interaction, you might have a different place between where the bad acts occurred and where the harm occurred. The harm, being to your body, creates a venue wherever you were when you sustained the harm.

The law offices of Hamilton and Associates typically deal with Missouri, Kansas, and Federal law. However, many of our client’s cases arise in jurisdictions different than the Midwest. In those cases, the client gets the benefit of more attorneys for the same cost. We partner up with attorneys local to your jurisdiction that are most versed with the particular court personnel, judges, juries, and the laws of your particular case. This allows you, the victim, to have both the specialized knowledge and experience of a drug error attorney regularly defending the families of victims of end stage renal failure, and also a local trial attorney regularly advocating for victims in your particular location. Often, both are needed.

There is a legal concept called a “statute of limitation.” This is a maximum period of time allowed by the law in which to file your claim. There are many claims that can be filed years and years in the future. For example, filing a contractual dispute can be delayed for a period as long as ten years. Medical malpractice cases are different. Pursuant to R.S.Mo. Section 516.105 (1998), any medical malpractice case must be brought within two years from the date of the occurrence. This is different than the date when you realized that harm had occurred. Rather, this is the two years from the date of the bad act.

There are some rare exceptions to statutes of limitation, like the two-year malpractice limitation period. For example, if your claim involves a foreign object being placed in your body, the victim is allowed two years from the date of discovering that foreign object in their body. In any event, the lawsuit cannot be brought more than ten years from the date of the wrongful act.

Another exception to the two-year limitation is when the victim is a “minor” child under the age of ten. The two year period would only give the child until their twelfth birthday. This has been held to be constitutionally invalid. Strahler v. St. Luke’s Hospital, 706 S.W.2d 7 (Mo. 1986).

Wrongful death cases under Missouri law are brought under that particular statute. This is R.S.Mo. Section 537.100 (1988) other revised statutes of Missouri. In medical malpractice, this is a three year statute of limitations. Caldwell v. Lester Cox Medical Centers-South, Incorporated, 943 S.W.2d 5 (Mo.App. 1997). One way or the other, immediate action is needed if you’re the victim of a drug error.

The law of Missouri is similar to other jurisdictions and is known as pure “comparative fault.” This was adopted in 1983 in the case of Gustafson v. Benda, 661 S.W.2d 11 (Mo. 1983). This was later codified in R.S.Mo. Section 537.765 (1988). Comparative Fault means that just because you are partially at fault for a particular harm you have suffered, you are not barred from recovery.

A judge or a jury in your jurisdiction will determine the percentage of fault each party will bear. Then, the damages are calculated. The percentage of fault that you might bear is multiplied by the amount of damages the victim has suffered. The wrongdoer then must pay the difference. For example, if a prescribing doctor is 90% at fault for failing to spot a drug interaction, and the damages are $100,000.00, the amount of the judgment is $90,000.00 (90% x $100,000.00 = $90,000.00).

Please note in your jurisdiction there may be other old laws, such as contributory fault. These antiquated legal concepts take a different approach. For example, in many jurisdictions, if it is found that you are more than 50% at fault for your harm, you cannot recover a thing. This is why it is so important to seek a lawyer with specialized knowledge and experience in this field who also pairs with local lawyers. That way you can know whether your claim is worth your time; you do not want to waste either your efforts or money.

This is a concept in the law known as “joint and several liability.” This is an interesting concept because it is constantly changing. Legislatures influenced by corporations like to eliminate joint and several liability because it protects wrongdoers from their own bad acts.

In Missouri, in 1988, the legislature renewed R.S.Mo. Section 538.230. This meant that multiple defendants who were at fault for victimizing a patient could be held collectively liable even when their portion/percentage of fault was less than the other wrongdoers. The legislature made a public policy decision that one of two parties had to pay for damages.

On one side, there were the bad actors. On the other side, there was the innocent victim. The legislature decided that the innocent victim should not pay the price for the harm inflicted upon them, just because one particular defendant had less money than the others.

Missouri recently again changed its joint and several liability law. It presently reads as follows:

Joint and several liability of defendants in tort actions, allocation of responsibility for judgment–defendants several liability for punitive damages. 

537.067. 1. In all tort actions for damages, if a defendant is found to bear fifty-one percent or more of fault, then such defendant shall be jointly and severally liable for the amount of the judgment rendered against the defendants. If a defendant is found to bear less than fifty-one percent of fault, then the defendant shall only be responsible for the percentage of the judgment for which the defendant is determined to be responsible by the trier of fact; except that, a party is responsible for the fault of another defendant or for payment of the proportionate share of another defendant if any of the following applies:

(1) The other defendant was acting as an employee of the party;

(2) The party’s liability for the fault of another person arises out of a duty created by the federal Employers’ Liability Act, 45 U.S.C. Section 51.

  1. The defendants shall only be severally liable for the percentage of punitive damages for which fault is attributed to such defendant by the trier of fact.
  2. In all tort actions, no party may disclose to the trier of fact the impact of this section.

(L. 1987 H.B. 700 § 41, A.L. 2005 H.B. 393)


Applicability of statute changes to cases filed after August 28, 2005, 538.305

(2001) Joint and several liability applies to Missouri Highway and Transportation Commission; application of statute would not require the public payment of a private debt or the unconstitutional diversion of appropriated highway funds. Smith v. Coffey, 37 S.W.3d 797 (Mo.banc.).

With regards to joint and several liability for drug error cases, it is particular important to discuss this with a lawyer teamed with a local attorney. This is because medical insurance coverage may depend upon the present status of this type of law.

Many states, including Missouri, have adopted a medical affidavit law. In Missouri, this is R.S.Mo. § 538.225. These types of statutes indicate that within a certain period of time (Missouri is 90 days) after you file your suit, an affidavit in writing must be filed with the court. That affidavit must be a writing signed under oath from a physician operating in the particular field in which you were victimized. That affidavit must state that your harm resulted from a medical error and was a result of a failure to use reasonable care under the circumstances. The harm you suffered must have been directly caused or directly contributed to be caused by that error. M.A.I. 4.01 (1980 Revision)

This expert testimony affidavit requirement is of particular import for drug error cases. Do not expect any money to be paid out prior to trial unless an expert affidavit is included. The wrongdoers who harmed you will simply wait. This is because if the affidavit never shows; you have no case.

Expect your drug error trial attorney to seek out and attempt to gain an affidavit before handling virtually any other area of the case. This is because it is an entry barrier to making a claim.

Virtually all states have enacted caps on medical malpractice actions. A cap is a maximum amount of money that can be given by the court.

Furthermore, many states have adopted maximum amounts of money that can be recovered in wrongful death cases. Sanders v. Ahmed, 364 S.W.3d 195 (Mo. banc 2012). For example, in Missouri, R.S.Mo. Section 538.210 (2015) caps non-economic damages for any particular suit. This amount is adjusted every year so you’ll need to contact the attorney to find out the current amount. Expect the amount to increase yearly at around 1.7%.

The maximum amount is calculated every year by the Director of the Division of Insurance and published in magazines, such as the Missouri Register. Missouri has a $406,800.00 cap on non-economic damages in medical negligence cases not resulting in death and a $711,900.00 cap non-economic damages in medical negligence cases resulting in death.  A cap marks the maximum amount of money you can hope to achieve in any particular case.

Caps on the amount of damages you may receive is an important reason to choose the right law firm. These laws are constantly changing. For example, in the case of Watts v. Lester E. Cox Medical Centers, 376 S.W.3d 633 (Mo. banc 2012), the Missouri Supreme Court held that such caps were unconstitutional. This fair ruling upheld the victim’s constitutional right to have a jury decide their case and award proper compensation. Other jurisdictions, can and often will differ.

This deals with a legal concept known as the “collateral source rule.” This is an old concept from the common law. It indicates that a wrongdoer cannot benefit from payments made before the wrongful act by the victim that would compensate the victim for losses. For example, in many cases, the victim (before the bad act) paid money to an insurance company for insurance coverage. If no accident happened, the victim would not get their money back from the insurance company for payment of premiums. Accordingly, collateral source rule states that the bad actor should not benefit from the payments of the victim by getting a reduction in the amount they should pay because of picking the right victim.

Unfortunately, the law of many jurisdictions has changed to allow the judge or jury to know that payments have been made for the victim’s bills. For example, Missouri Supreme Court case of Washington v. Barnes Hospital, 897 S.W.2d 611 (Mo. banc 1995) and current statutory laws presently allow evidence to come in of some payments for medical bills from insurance. More pointedly, is the new law allowing the negotiated down rate by the insurance company to come in evidence. This reduces case value in some circumstances.

About the Authors

Doctor KK Vouthy

  • Clinical Pharmacist (Pharm.D.)
  • Clinical Microbiologist
  • Hematologist
  • Clinical Laboratory Scientist

Matthew Hamilton

  • Juris Doctor
  • Trial Attorney

[1] Mayo Foundation for Medical Education and Research (MFMER). Mayo Clinic Disease and Conditions Web Site. Serotonin Syndrome. http://www.mayoclinic.org/diseases-conditions/serotonin-syndrome/home/ovc-20305669. Accessed February 12, 2017.

[2] U.S. Department of Health and Human Services National Institutes of Health. MedlinePlus. Serotonin Syndrome. https://medlineplus.gov/ency/article/007272.htm. Published February 7, 2017. Accessed February 12, 2017.