OPINION
J. HARVEY HUDSON, Justice.On its own motion, the court withdraws its memorandum opinion of March 16, 2004 and substitutes the following majority and dissenting opinions.
Appellants, Bessie Winston and James Winston (‘Winstons”) appeal the grant of summary judgment in favor of Appellee, William H. Peterek, M.D. (“Dr. Peterek”). The Winstons brought their medical malpractice suit after Mrs. Winston suffered from a ruptured cerebral aneurysm and subarachnoid hemorrhages. Dr. Peterek filed his motion for partial summary judgment arguing the Winstons’ claims were barred by limitations. We affirm.
The Winstons originally brought suit against Dr. Peterek and the Gulf Coast Medical Group Family Practice. After giving notice to Dr. Peterek of their claim pursuant to Article 4590i, Section 4.01 of the Revised Civil Statutes1 in October, 2000, the Winstons filed their suit on January 2, 2002. After the trial court granted Dr. Peterek’s motion for partial summary judgment, the claims against Dr. Peterek were severed from the claims against the medical group; thus, a final judgment was rendered in favor of Dr. Peterek.
Dr. Peterek began treating Winston for hypertension on October 13, 1993. Dr. Peterek initially prescribed Procardia XL on October 13, 1993. He also prescribed Anaprox on or about June 27, 1994. Winston’s last office visit with Dr. Peterek was on April 3,1998. Subsequently, Dr. Peter-ek’s office made calls to refill the prescription for Procardia on February 9, 1999, and October 5,1999. A call was also made on November 19, 1998, to refill a prescription for Anaprox. The record is silent, and the parties do not assert, that any future office visits were scheduled. Winston sustained her injuries on November 5, 1999.
To prevail on a motion for summary judgment, a defendant must establish that no material fact issue exists and that it is entitled to judgment as a matter of law. Rhone-Poulenc, Inc. v. Steel, 997 S.W.2d 217, 222 (Tex.1999). Once the defendant establishes that no genuine issue of material fact exists regarding an element of the plaintiffs claim, the plaintiff must present competent summary judgment evidence raising a fact issue on that element. Guest v. Cochran, 993 S.W.2d 397, 401 (Tex.App.Houston [14th Dist.] 1999, no pet.). In *207conducting our review of the summary judgment, we take as true all evidence favorable to the nonmovant, and make all reasonable inferences in the nonmovant’s favor. KPMG Peat Marwick v. Harrison County Hous. Fin. Corp., 988 S.W.2d 746, 748 (Tex.1999). A defendant, as movant, is entitled to summary judgment if it either disproves at least one essential element of each of the plaintiffs causes of action or establishes all the elements of an affirmative defense. Am. Tobacco Co. v. Grinnell, 951 S.W.2d 420, 425 (Tex.1997). By moving for summary judgment, Dr. Peter-ek has the burden to show as a matter of law that the Winstons’ suit is barred by limitations. Delgado v. Burns, 656 S.W.2d 428, 429 (Tex.1983) (per curiam).
Texas law imposes a two-year statute of limitation on health care claims. Tex. Civ. Prac. & Rem.Code Ann. § 74.251 (Vernon Supp.2004).2 The limitations period is measured from one of three dates: (1) occurrence of the breach or tort, (2) date that the relevant course of treatment was completed, or (3) last date of the relevant hospitalization. Id.; Kimball v. Brothers, 741 S.W.2d 370, 372 (Tex.1987). A plaintiff is not permitted to choose the measurement most favorable to its case. Shah v. Moss, 67 S.W.3d 836, 841 (Tex.2001). A reviewing court must first determine whether the date of the alleged tort is ascertainable. If the date is not ascertainable, then the court must employ a course of treatment analysis in order to determine the last day of treatment. Kimball, 741 S.W.2d at 372. Naturally, the plaintiff must establish a course of treatment under this analysis. Shah, 67 S.W.3d at 841. However, if the date of the alleged tort or breach is known, the limitations run from that date. Id. at 843. The ascertainable date controls irrespective of the plaintiffs attempt to establish a course of treatment. Id. at 843-44.
The Winston’s alleged in their petition that “Peterek continued to misdiagnose Plaintiffs condition over the phone .... [and] continued to prescribe hypertension and pain medication despite the medication’s apparent ineffectiveness.” More specifically, the Winstons alleged in their petition that Dr. Peterek was negligent in: (1) In failing to properly perform medical treatment; (2) failing to examine upon presentment of symptoms; (3) prescribing medication without a physical examination; (4) failing to use proper diagnostic procedures in connection with Winston’s symptoms; and (5) fading to recognize and/or acknowledge the symptoms resulting from his treatment. The Winstons do not allege that the prescribed medications were the cause of her injury; rather, the Winstons’ complaints arise out of Dr. Peterek’s failure to correctly discover, treat, or prevent Mrs. Winston’s subsequent injuries through appropriate follow-up care.
Allegations of misdiagnosis necessarily require a reviewing court to use the date of the last visit with the physician in a limitations analysis. See Rowntree v. Hunsucker, 833 S.W.2d 103, 108 (Tex.1992). Likewise, a physician’s “negligent failure to conduct follow-up procedures” occurs only “in connection with the [last] examination.” Bala v. Maxwell, 909 S.W.2d 889, 892 (Tex.1995). The theory in such cases is that when a physician negligently fails to provide weekly or monthly follow-up treatment, the breach of duty imposed by the standard of care occurs on the last date the physician actually saw the patient. Shah, 67 S.W.3d at 844.
*208Appellants argue that Mrs. Winston was injured by a “course of treatment.” However, the gist of their complaint is not that the medications prescribed by Dr. Peterek caused the injury, but that his lack of follow-up care caused the injury. As the Texas Supreme Court observed, “[wjhile the failure to treat a condition may well be negligent, we cannot accept the self-contradictory proposition that the failure to establish a course of treatment is a course of treatment.” Roumtree, 833 S.W.2d at 105-06 (quoting from Nykorchuck v. Henriques, 78 N.Y.2d 255, 573 N.Y.S.2d 434, 437, 577 N.E.2d 1026, 1029 (1991)).
Appellants also seem to contend that a “course of treatment” is supported here by the fact that Mrs. Winston obtained additional refills of her prescription medication by calling Dr. Peterek well after her last visit. However, the Texas Supreme Court has not supported a rule that would extend the statutory limitations period until, all authorized prescription refills are obtained. Rowntree, 833 S.W.2d at 107 (finding such a rule “unworkable”).3 In order to use a course-of-treatment analysis in connection with prescription drugs, the alleged drug treatment must be the direct cause of the injury. See id. at 105. Here, the Winstons’ claims center on Dr. Peterek’s negligent follow-up care. For example, the Winstons’ expert stated in his affidavit:
Mrs. Winston’s specific case of hypertension required follow-up medical services throughout the time she was being treated for hypertension with medication. Mrs. Winston required medical examinations and monitoring to verify the effectiveness of the medication and to make medication or other adjustments if necessary to reduce her blood pressure below hypertension levels.
Absent from the record is an allegation that it was the drug that caused the injury. Based upon the Winstons’ allegations, any breach would have occurred during the last visit on April 3, 1998, which is an ascertainable date. Having established an ascertainable date, we do not conduct a course-of-treatment analysis. Shah, 67 S.W.3d at 843-44.
*209Accordingly, the trial court did not err in granting summary judgment. The Win-stons filed their lawsuit over three years from the date of last examination. Thus, they are barred by limitations. We affirm the judgment of the trial court.
. This provision was formerly found at Tex. Rev.Civ. Stats. Ann. Art. 4590i, § 4.01(c). Medical Liability and Insurance Improvement Act of Texas, 65th Leg., R.S., ch. 817, § 4.01(c), 1977 Tex. Gen. Laws.2039, 2047, repealed, by Act of June 11, 2003, 78th Leg., R.S., ch. 204, § 10.09, 2003 Tex. Gen. Laws. 847, 884. The provision may now be found at Section 74.051(c) of the Civil Practice and Remedies Code.
. Effective September 1, 2003, the provisions found at Article 4590i of the Revised Civil Statutes are now found in Chapter 74 of the Civil Practice and Remedies Code. Act of June 11, 2003, 78th Leg., R.S., ch. 204, § 10.01, 2003 Tex. Gen. Laws. 847, 864.
. The Winstons argue that we should confine our analysis to those cases involving prescription drugs. An analysis of the facts of Gross v. Kahanek, 3 S.W.3d 518 (Tex.1999) (per curiam) and Rowntree v. Hunsucker, 833 S.W.2d 103 (Tex.1992) instructs us as to why we are not required to consider additional prescription refills. We acknowledge that in cases where a prescribed drug is the cause of an injury that the limitations would run from the last drug treatment. Gross, 3 S.W.3d at 521; Rowntree, 833 S.W.2d at 105. However, the present case can be both likened and distinguished with Gross and Rowntree.
The crucial inquiry is whether the plaintiff alleges injuries directly caused by the prescribed drug. The plaintiff in Gross was prescribed a drug, Tegretol, and the claim specifically arose out of the use of the drug. 3 S.W.3d at 520. The plaintiff's alleged multiple acts of negligence, including a failure to monitor and maintain an appropriate level of Tegretol. Id. The record also contained evidence that Tegretol poisoning contributed to the complainant’s death. Id. Conversely, the plaintiff in Rowntree was being treated for hypertension and subsequently suffered a stroke. 833 S.W.2d at 104. The plaintiff attempted to extend the period of limitations by arguing that the course of treatment necessarily included the time period that plaintiff was taking prescription drugs. Id. at 105. Notwithstanding subsequent prescription refills and appointments for unrelated conditions, the supreme court used the date of the last hypertension-related visit in upholding summary judgment on limitations. Id. at 108-09. The supreme court found it determinative that the plaintiff was not complaining that the drug caused the harm; the plaintiff even conceded that the drug was appropriately prescribed. Id. at 105, 108.