Can skipping a dose of testosterone replacement therapy (TRT) cause palpitations?

Can Skipping a Dose of Testosterone Cause Palpitations?

Yes, skipping a dose of testosterone replacement therapy can potentially cause palpitations due to fluctuating hormone levels, particularly with injectable formulations that create peaks and valleys in testosterone levels.

Mechanism and Evidence

Testosterone replacement therapy (TRT) affects the cardiovascular system in several ways. When patients skip doses, particularly with injectable testosterone preparations, they may experience significant fluctuations in hormone levels that can impact cardiovascular function:

1. Injectable testosterone formulations create a "roller coaster" effect characterized by alternating periods of symptomatic benefit and return to baseline symptoms, corresponding to fluctuations in serum testosterone levels 1. These fluctuations can manifest as palpitations during the "valley" periods when testosterone levels drop.

2. Cardiovascular effects of testosterone: Studies suggest that testosterone has direct effects on coronary artery diameter and blood flow 1. Abrupt changes in testosterone levels may temporarily affect these parameters, potentially leading to palpitations.

3. Timing of fluctuations: For patients receiving testosterone injections, levels typically peak 2-5 days after injection and return to baseline 10-14 days after injection 1. Palpitations are more likely to occur as levels decline toward the end of the dosing interval.

Risk Factors for Palpitations When Skipping Doses

The likelihood of experiencing palpitations when skipping testosterone doses depends on several factors:

• Type of testosterone preparation: Injectable formulations (especially testosterone enanthate and cypionate) are more likely to cause palpitations when doses are missed compared to transdermal preparations (gels, patches) that provide more stable hormone levels 1.

• Individual sensitivity: Some patients are more sensitive to hormonal fluctuations than others.

• Baseline cardiovascular health: Patients with pre-existing cardiovascular conditions may be more susceptible to palpitations with testosterone fluctuations.

Management Recommendations

To minimize the risk of palpitations related to testosterone therapy:

1. Maintain consistent dosing schedule: Adherence to prescribed dosing intervals is critical, especially with injectable formulations.

2. Consider alternative formulations: For patients experiencing significant fluctuations with injections, transdermal preparations (gels or patches) may provide more stable testosterone levels 1.

3. Optimal monitoring: Testosterone levels should be tested 2-3 months after treatment initiation and/or after any dose change. For patients on injections, levels should be measured midway between injections, targeting a mid-normal value (500-600 ng/dL) 1.

4. Dosing adjustments: More frequent but lower-dose injections (e.g., weekly rather than biweekly) may help reduce fluctuations and associated symptoms 1.

Important Considerations

• While palpitations can occur with testosterone therapy, studies have not demonstrated an increased incidence of serious cardiovascular events such as myocardial infarction, stroke, or angina with appropriate testosterone replacement 1.

• The cardiovascular safety profile of testosterone therapy appears generally favorable when used appropriately in patients with true hypogonadism 1.

• If palpitations persist despite optimizing the dosing regimen, further cardiovascular evaluation may be warranted to rule out other causes.