Understanding the Pharmacologic Options for Treating Myxedema in Hypothyroidism vs Hyperthyroidism
Are the symptoms of hyperthyroidism and hypothyroidism as different as patients think? Most know that weight gain and feeling cold are signs of hypothyroidism, and figure hyperthyroidism is the opposite. But it’s not that simple. Overlapping symptoms and use of generic terms lead to confusion. So it’s no surprise that the term “myxedema” might cause some head scratching as it’s associated with different skin manifestations in both types of thyroid dysfunction. When pharmacists have the opportunity to counsel patients with thyroid disease, they should be prepared to answer questions and correct misunderstandings related to myxedema and skin problems.
Role of Thyroid Hormones in Skin
Even though the function of thyroid hormones in the skin remains the subject of research, experts agree they have a significant influence. Thyroid hormones stimulate protein synthesis and oxygen consumption in the epidermis. They regulate the proliferation and differentiation of epidermal keratinocytes. They’re also involved in sebum production and the function of dermal fibroblasts, which in turn affect the skin barrier. In other words, thyroid disease alters the skin’s architecture and disrupts homeostasis, which makes skin problems common in patients with a malfunctioning thyroid gland.
Skin problems in patients with thyroid disease are usually listed this way:1
- Moist skin / hyperhidrosis
- Generalized pruritus
- Chronic urticaria
- Diffuse skin pigmentation
- Dry, rough skin
- Hyperkeratotic epidermis
- Diffuse myxedema
In spite of these distinct lists, dermatological symptoms may overlap, according to a study in the European Journal of Internal Medicine. The researchers found that chronic urticaria, vitiligo and pruritus occur more often in those with thyroid disease than healthy patients. However, there were no statistical differences in skin manifestations between those with hyperthyroidism, hypothyroidism and euthyroidism.2 An article in Dermatology Times also states that skin problems such as lesions are often non-specific signs of both hyperthyroidism and hypothyroidism.3
Manifestations of Myxedema
When patients with thyroid disease come to your pharmacy, they’re likely to be confused over myxedema—and not just because it’s an unusual word. If you do an Internet search for “myxedema,” most of the results will either call it a “severe form of hypothyroidism” or show that it’s synonymous with “myxedema coma.” Imagine how that will frighten your patient, especially if they didn’t get a good explanation from the doctor or didn’t quite understand what they were told.
Myxedema refers to increased deposits of glycosaminoglycans under the skin, usually hyaluronic acid. 4 When used generically, myxedema is a classic cutaneous sign of hypothyroidism that results in puffy face, hands or feet. Distinct changes in the face include swollen lips and a thickened nose. In this manifestation, the skin does not pit with pressure. However, as the Internet search shows, myxedema is also generally used to mean myxedema coma, which is a rare and life-threatening condition defined as severe hypothyroidism with physiological decompensation. Myxedema coma, or crisis, occurs in patients with chronic, undiagnosed hypothyroidism and presents a medical emergency.
Patients with hyperthyroidism also experience myxedema, but in a different presentation. In this case, it’s called pretibial myxedema or thyroid dermopathy, rather than simply myxedema. It’s often localized to the pretibial area and lower extremities, but the glycosaminoglycan accumulations can occur anywhere. It may appear as slightly discolored, thickened skin, or the patient may also have raised, yellowish-brown lesions. While thyroid dermopathy is almost always associated with Graves’ disease, especially in patients with Graves’ ophthalmopathy, it’s also associated with hypothyroidism.5
Treatment Options for Myxedema and the Role of Pharmacists
Over-the-counter skin treatments are one of the top five best-selling products in pharmacies.6 Among these customers, you’ll find patients with undiagnosed thyroid disease because dermatological problems are often one of the first symptoms of an under- or over-active thyroid. While it’s not practical to try and target every patient buying products for dry or itchy skin, you can still reach out to this group by using posters or handouts that give them a heads-up about the association of skin problems and thyroid disease. For example, a poster might ask if they have a skin condition that isn’t healing, then suggest they talk to the pharmacist.
In addition to medications used to restore the proper balance of thyroid hormones, and oral pain relief if necessary, the treatment of skin manifestations follows the protocols for dermatitis, urticaria and pruritus. Topical skin therapy may include any combination of the following options:
- Skin barrier maintenance is essential. Whether the patient has dry skin or severe dermatitis, they need to regularly moisturize. Petrolatum applied to wet skin is recommended, but many patients will prefer lighter creams and ointments.
- Topical steroids are the primary treatment for thyroid-related skin conditions, including myxedema. Potency is determined by the severity of the outbreak, but thyroid dermopathy may require potent topical steroids.
- Calcineurin inhibitors are considered for second-line therapy.
- Antihistamines such as hydroxyzine and diphenhydramine relieve pruritus.
- Tricyclic antidepressants are used for their antihistamine effect.
- Pentoxifylline is sometimes used to treat thyroid dermopathy.
Help Patients Make Sense of Myxedema in Hypothyroidism and Hyperthyroidism
Hypothyroidism is highly treatable, but turns into a progressive disease when it goes undiagnosed. Of course, hyperthyroidism is also treatable, but it can be more challenging than hypothyroidism, depending on the underlying cause. Hyperthyroidism also increases the risk of systemic complications such as cardiac arrhythmias. One of the best services you can provide for your patients is making them aware of thyroid disease. Remember that you may be the first health professional they meet as they self-treat skin conditions, so don’t hesitate to find ways to intervene and talk to them about myxedema, rashes and thyroid disease.
Pharmaceutica North America provides high-quality prescription topical steroids, bulk active pharmaceutical ingredients, and OTC supplements to treat skin conditions. Contact us today to talk about how we can support your pharmaceutical needs.
- “An Intimate Relationship Between Thyroid Hormone and Skin: Regulation of Gene Expression,” August 2013, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3749490/ ↩
- “Skin Findings in Thyroid Disease,” March 2009, http://www.ncbi.nlm.nih.gov/pubmed/19327604 ↩
- “Skin Symptoms Can Be Linked to Thyroid Disease,” May 2010, http://dermatologytimes.modernmedicine.com/dermatology-times/news/modernmedicine/modern-medicine-feature-articles/skin-symptoms-can-be-linked-t ↩
- “Thyroid Hormone Action on Skin,” July 2011, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3219173/ ↩
- “Pretibial Myxedema Associated with Euthyroid Hashimoto’s Thyroiditis: A Case Report,” June 2014, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4129354/ ↩
- “What’s Hot in the Pharmacy Front End?” December 2015, http://smartretailingrx.com/patient-care-counseling/whats-hot-in-the-pharmacy-front-end/ ↩