our Moorestown, NJ headquarters. The remaining increase was primarily attributable to increases in information technology spending and travel costs due to support development efforts.
Sales and Marketing Expenses
Sales and marketing expenses increased $11.6 million, or 166%, from $7.0 million for the nine months ended September 30, 2018 to $18.6 million for the comparable period in 2019. The acquisitions of Peak PACE, Mediture, Cognify, DoseMe and PrescribeWellness contributed $7.4 million to the increase, which primarily related to employee compensation costs. Excluding the acquisitions, the increase in sales and marketing expense was primarily due to a $3.8 million increase in personnel costs related to an increase in stock compensation expenses, additional headcount to support the expansion of our sales team, and increases in salaries and benefits related to market adjustments and performance-based increases for our existing employees. The remaining increase in sales and marketing expenses was primarily due to a $452 thousand increase in conference and other travel costs related to business development activities.
General and Administrative Expenses
General and administrative expenses increased $18.6 million, or 92%, from $20.2 million for the nine months ended September 30, 2018 to $38.8 million for the comparable period in 2019. The acquisitions of Peak PACE, Mediture, Cognify, DoseMe, and PrescribeWellness contributed $8.0 million to the increase in expenses, which consisted primarily of employee compensation costs, including stock compensation, information technology expenses, business insurance costs, and rent and utilities expenses. Excluding the acquisitions, higher employee compensation costs of $6.2 million were primarily due to an increase in stock compensation of $4.1 million related to equity awards granted during 2019, an increase in headcount to support the overall growth of our operations, and increases in salaries and benefits for existing employees related to market adjustments and performance-based increases. In addition, general and administrative expenses increased $2.3 million as a result of acquisition related transaction costs related to the acquisitions of DoseMe and PrescribeWellness in 2019. Professional service fees primarily related to audit, tax and internal control services and legal fees represented $1.6 million of the increase. The remaining increase is primarily attributable to increased information technology expenses due to operational growth.
Acquisition-related Contingent Consideration Expense
During the nine months ended September 30, 2019 and 2018, there was a $4.5 million and a $40.4 million charge incurred, respectively, related to the fair value adjustments of our acquisition-related contingent consideration liabilities.
During the nine months ended September 30, 2019, we recorded a $3.7 million charge to increase the fair value of the Cognify acquisition-related contingent consideration primarily due to an amendment of certain definitions used in the calculation of the contingent consideration set forth in the stock purchase agreement, and the decreased discount period to the final measurement date. The Cognify contingent consideration is based on a multiple of the excess of Cognify’s 2021 revenues and EBITDA over its 2018 revenues and EBITDA, as defined in the stock purchase agreement. As of September 30, 2019, the Cognify contingent consideration liability was $11.5 million with the potential for up to an additional $2.5 million to be earned if the maximum contingent amount is earned, which would flow through as a charge to net income or loss. The final amount of the Cognify acquisition-related contingent consideration liability will be fixed as of December 31, 2021.
During the nine months ended September 30, 2019, we recorded a charge of $30 thousand related to the fair value adjustment of the final DoseMe acquisition-related contingent consideration amount. We elected to accelerate the payment of the DoseMe contingent consideration and made a final cash payment during the third quarter of 2019.
During the nine months ended September 30, 2019, we recorded a $624 thousand charge related to the fair value adjustment of the final SRx acquisition-related contingent consideration amount. During the nine months ended September 30, 2018, we recorded a $40.1 million charge related to the fair value adjustments of the SRx acquisition-related contingent consideration liabilities. The SRx acquisition-related contingent consideration liability was paid in full during the first quarter of 2019.
During the nine months ended September 30, 2019, we recorded a $163 thousand remeasurement charge related to the Peak PACE acquisition-related contingent consideration as a result of final purchase price adjustments. During the