When an antidepressant isn’t: What dental hygienists need to know about SSRIs

If you have heard me present continuing education seminars and webinars, you know that I always stress the importance of the dental hygienist’s role in obtaining a complete and accurate patient medical history. While patients may sometimes be the worst reporters of their own medical history, a dental hygienist can obtain information crucial for patient management and treatment planning by simply asking these three questions:

1. What do you take?
2. Why do you take it?
3. Did you take it today?

The second question may be the most important. Medications are often used to treat a wide variety of conditions, so it is imperative to ascertain why the patient is taking it. Assuming is not an option and can lead to negative outcomes. There may be no better example of this point than the medications we commonly refer to as SSRIs.

How do SSRIs work?

Selective serotonin reuptake inhibitors, or SSRIs, work by selectively blocking the reuptake of serotonin in the brain.¹ Serotonin is a neurotransmitter involved in regulating mood and emotions as well as other physiological processes, including pain modulation. Common SSRIs include fluoxetine (Prozac), sertraline (Zoloft), and escitalopram (Lexapro). The mechanism of action of SSRIs is fascinating and may explain why these drugs are used for more than just treating depression.

As their name suggests, SSRIs inhibit the reuptake of serotonin by blocking the serotonin transporter protein, which is responsible for removing serotonin from the synaptic cleft between neurons.¹ By blocking reuptake, SSRIs increase the concentration of serotonin in the synaptic cleft, which leads to enhanced serotonin signaling and, thus, more prolonged and increased activation of serotonin receptors on the postsynaptic neuron.

Also by Tom Viola ... The patient behind the mask: What every dental hygienist needs to know about Parkinson's disease

This enhanced serotonin signaling, particularly at specific receptor subtypes (such as 5-HT1A and 5-HT2A receptors), influences the transmission of electrical signals between neurons, which helps regulate both mood and emotions. In addition, long-term use of SSRIs is believed to promote neuroplasticity, which refers to the brain’s ability to change and adapt.² This may involve the growth and reorganization of neural connections, leading to improved mood regulation and resilience to stress over time.

Why are SSRIs prescribed?

While classified as antidepressants, it is of utmost importance to be aware that SSRIs are commonly prescribed for a wide variety of mental health conditions. Of course, SSRIs are frequently prescribed as a first-line treatment for major depressive disorder (MDD).³ They help alleviate symptoms of depression, such as persistent sadness, loss of interest, and changes in appetite or sleep patterns.

However, SSRIs are also effective in managing generalized anxiety disorder (GAD), a condition characterized by excessive and uncontrollable worry and anxiety.⁴ These medications can help reduce anxiety symptoms, promote relaxation, and improve overall well-being. SSRIs are also prescribed to individuals with social anxiety disorder (SAD) to alleviate symptoms of anxiety related to social situations.⁵ SSRIs can help reduce fear, nervousness, and excessive self-consciousness.

Also by Tom Viola ... Why patient self-medication with dietary supplements matters to dental hygienists

For individuals with panic disorder, which involves recurrent panic attacks and anxiety about future attacks, SSRIs can be prescribed to reduce the frequency and severity of panic attacks and help manage the associated anxiety.⁶ SSRIs are also often used as a first-line treatment for obsessive-compulsive disorder (OCD).⁷ They help reduce obsessive thoughts and compulsive behaviors, allowing individuals to better manage their condition. Finally, SSRIs may be prescribed as part of a comprehensive treatment approach for post-traumatic stress disorder (PTSD)⁸ to help manage symptoms such as intrusive thoughts, nightmares, and hyperarousal.

Beyond their use for the treatment of mental health conditions, SSRIs may also be prescribed for the management of certain types of chronic pain.⁹ While the use of SSRIs for chronic pain is considered off-label (meaning it is not their primary approved use but may be prescribed by health-care professionals based on their own clinical judgment), SSRIs have shown effectiveness in managing some types of neuropathic pain. Their mechanism of action in promoting analgesia in these conditions, such as diabetic neuropathy, postherpetic neuralgia (shingles), and nerve compression syndromes, is not entirely understood. It is believed that the modulation of serotonin signaling may play a role in reducing pain.⁹

In addition to their potential pain-relieving properties, SSRIs can also help manage other associated symptoms often present in individuals with chronic pain, such as depression, anxiety, and sleep disturbances. By addressing these coexisting conditions, SSRIs may improve overall well-being and quality of life.

Dental implications of SSRIs

Interestingly, while very few studies have investigated the use of SSRIs in the treatment of burning mouth syndrome (BMS), there is some evidence to suggest their possible therapeutic effects.¹⁰ BMS is a condition characterized by a burning or scalding sensation in the mouth, often accompanied by a dry mouth, altered taste, and general oral discomfort. In certain cases, SSRIs may be prescribed to help manage the pain associated with BMS. Although their mechanism of action is not entirely understood, it is believed that the modulation of serotonin signaling may play a role in reducing pain perception. Ironically, however, there is also one case report of BMS resulting from SSRI therapy.¹¹

SSRIs have adverse effects that are of great significance in dentistry. One of the most common oral side effects of SSRIs is xerostomia. Some individuals may experience bruxism or clenching as a side effect of SSRIs. In addition, SSRIs can potentially increase the risk of bleeding due to their effects on platelet function.¹² Due to the effect of serotonin on bone metabolism, there is also some evidence to suggest that SSRIs may increase the risk of dental implant failure.¹³

Finally, most antidepressants, including SSRIs, carry a black box warning issued by the FDA that highlights an increased risk of suicidal ideation or behavior, particularly in children, adolescents, and young adults.¹⁴ This risk is most commonly observed during the first few weeks of starting or adjusting the dosage of antidepressant medications.

As dental hygienists, it is important to be aware of all the prescription medications, OTC drugs, dietary supplements, and other substances our patients are using. However, in addition to the “what,” it is of equal (and maybe even greater) importance to understand the “why” our patients are taking these medications. This is especially true with SSRIs, which have multiple approved and off-label indications for use. 

Editor's note: This article appeared in the September 2023 print edition of RDH magazine. Dental hygienists in North America are eligible for a complimentary print subscription. Sign up here.

References

1. Nutt DJ, Forshall S, Bell C, et al. Mechanisms of action of selective serotonin reuptake inhibitors in the treatment of psychiatric disorders. Eur Neuropsychopharmacol. 1999;9(Suppl 3):S81-S86.
   doi:10.1016/s0924-977x(99)00030-9
2. Andrade C, Rao NSK. How antidepressant drugs act: a primer on neuroplasticity as the eventual mediator of antidepressant efficacy. Ind J Psychiatry. 2010;52(4):378-386. doi:10.4103/0019-5545.74318
3. Jakobsen JC, Katakam KK, Schou A, et al. Selective serotonin reuptake inhibitors versus placebo in patients with major depressive disorder. A systematic review with meta-analysis and trial sequential analysis. BMC Psychiatry. 2017;17(1):1-28. doi:10.1186/s12888-016-1173-2
4. Reinhold JA, Mandos LA, Rickels K, Lohoff FW. Pharmacological treatment of generalized anxiety disorder. Expert Opin Pharmacother. 2011;12(16):2457-2467. doi:10.1517/14656566.2011.618496
5. Blanco C, Bragdon LB, Schneier FR, Liebowitz MR. The evidence-based pharmacotherapy of social anxiety disorder. Int J Neuropsychopharmacol. 2013;16(1):235-249. doi:10.1017/S1461145712000119
6. Sheehan DV, Harnett-Sheehan K. The role of SSRIs in panic disorder. J Clin Psychiatry. 1996;57(Suppl 10):51-58.
7. Soomro GM, Altman DG, Rajagopal S, Oakley-Browne M. Selective serotonin re-uptake inhibitors (SSRIs) versus placebo for obsessive compulsive disorder (OCD). Cochrane Database Syst Rev. 2008;2008(1):CD001765. doi:10.1002/14651858.CD001765.pub3
8. Asnis GM, Kohn SR, Henderson M, Brown NL. SSRIs versus non-SSRIs in post-traumatic stress disorder: an update with recommendations. Drugs. 2004;64(4):383-404. doi:10.2165/00003495-200464040-00004
9. Lee YC, Chen PP. A review of SSRIs and SNRIs in neuropathic pain. Expert Opin Pharmacother. 2010;11(17):2813-2825. doi:10.1517/14656566.2010.507192
10. Fleuret C, Le Toux G, Morvan J, et al. Use of selective serotonin reuptake inhibitors in the treatment of burning mouth syndrome. Dermatol. 2014;228(2):172-176. doi:10.1159/000357353
11. Raghavan SA, Puttaswamiah RN, Birur PN, Ramaswamy B, Sunny SP. Antidepressant-induced burning mouth syndrome: a unique case. Korean J Pain. 2014;27(3):294-296. doi:10.3344/kjp.2014.27.3.294
12. Fratto G, Manzon L. Use of psychotropic drugs and associated dental diseases. Int J Psychiatry Med. 2014;48(3):185-197. doi:10.2190/PM.48.3.d
13. Gupta B, Acharya A, Pelekos G, Gopalakrishnan D, Kolokythas A. Selective serotonin reuptake inhibitors and dental implant failure—a significant concern in elders? Gerodontology. 2017;34(4):505-507. doi:10.1111/ger.12287
14. Suicidality in children and adolescents being treated with antidepressant medications. U.S. Food and Drug Administration. Updated February 5, 2018. https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/suicidality-children-and-adolescents-being-treated-antidepressant-medications