OPINION
TERRY JENNINGS, Justice.
A jury found appellant, Brodrick De-chone Delane, also known as Broderick Shun Delane, also known as Shaun Scott, guilty of the felony offense of driving while intoxicated.1 After appellant pleaded true to two enhancement allegations that he had twice been previously convicted of felony offenses, the jury assessed his punishment at confinement for thirty-five years.2 In two issues, appellant contends that the evidence is legally and factually insufficient to support his conviction and the trial court erred in admitting “unreliable and irrelevant scientific evidence.”
We reverse and remand.
Background
A Harris County grand jury issued a true bill of indictment, accusing appellant of driving while intoxicated “by reason of the introduction of a controlled substance, a drug, a dangerous drug, a combination of two or more of those substances, or any other substance into the body.” Prior to trial, appellant filed a “motion in limine to suppress drug/medication evidence,” seeking to suppress “audio or visual evidence pertaining directly or indirectly to [his] use of any drug or medication, on grounds that such evidence is irrelevant and its effect would be more prejudicial than probative without expert scientific testimony to provide the proper foundation.”
During the trial court’s hearing on his motion to suppress evidence, appellant asserted that the State was required to present expert testimony about his alleged ingestion of medications and the effects of the medications on him. The State responded that, under the circumstances and given the training, education, and experience of the police officer who had arrested appellant, the officer was qualified to testify to his opinion that appellant was impaired by the medications. The trial court denied appellant’s motion.
At trial, Houston Police Department (“HPD”) Officer L. Morrison testified that on September 21, 2008, while assigned to protect a “point of distribution” (“POD”) that had been set up to assist Houstonians in the aftermath of Hurricane Ike, a woman told him about a man who was driving a car “crazy,” had almost hit her car, and had run “a bunch of cars off of the road.” The woman identified the car, which appellant was driving. Morrison followed appellant, who was traveling at ten-miles per hour in a thirty-mile per hour zone, and Morrison saw appellant travel through a stop sign and a red blinking traffic light without stopping or yielding to other traffic. Appellant almost caused his car to strike another car, which had honked its [415]*415horn and maneuvered to avoid appellant’s car. Appellant “bounc[ed]” his car “from curb to curb” and drove in a “dangerous” manner. Morrison activated his emergency lights, and appellant, in trying to stop his car, “jumped” a curb, drove across some grass, and almost hit a fence. After appellant stepped out of his car, he held onto it for support. After Morrison approached and identified himself to appellant, he explained that he had stopped appellant for reckless driving. Appellant then “fumbled” as he looked for his identification, and he also slurred his speech. However, Morrison did not detect any odor of alcohol.
Officer Morrison described appellant as “slow to react,” and he decided to administer field-sobriety tests to appellant. Appellant was not able to perform the “one-leg-stand” and “walk-and-turn” tests because he could not stand on his own. After Morrison asked appellant if he had any “medical issues,” appellant stated that he was “fine.” Morrison then administered the horizontal-gaze-nystagmus (“HGN”) test to appellant, who exhibited the “maximum number of clues” to indicate intoxication. Based upon the results of this test, Morrison “knew that [appellant] was under the influence of a central nervous system depressant.” Morrison also administered to appellant the “vertical nystagmus” test, during which appellant exhibited “both clues” and “immediate onset,” which demonstrated “a very high level of intoxicants” in appellant’s system. Finally, Morrison administered to appellant a “convergence test,” which showed that appellant tested “positive for that clue as well.” Morrison then helped appellant into Morrison’s patrol car because appellant was not able to walk without support.
Appellant told Officer Morrison that he had taken two different prescription medications. After Morrison asked appellant why he was taking medications, appellant was “very difficult to understand,” had “very slurred speech,” and mumbled. When Morrison conducted an inventory of appellant’s car, he found two prescription medication bottles, one containing Lisino-pril and the other Pyridoxine, which belonged to appellant. Morrison explained that he was “familiar” with Lisinopril, a heart medication, because he had a “nursing drug handbook,” which, he explained, stated that Lisinopril “causes drowsiness and ataxia,” “the inability to walk.”
Officer Morrison further testified that Lisinopril would not have caused appellant to exhibit the “indicators” that Morrison had observed when he administered the HGN test to appellant. After appellant objected to this evidence on the ground that it constituted “scientific testimony,” the trial court overruled the objection. Morrison then explained that even though Lisinopril “caused ataxia and drowsiness, it is not a [central nervous system] depressant to where it will cause overwhelming signs,” like those appellant exhibited at the scene. When asked whether he had observed any warning labels on the Lisino-pril prescription bottle,3 Morrison stated that the bottle contained a warning label stating, “Do not drive or operate heavy machinery.”
In regard to Pyridoxine, Officer Morrison explained that his drug handbook for nurses stated that it also caused ataxia. After referring to his notes in his arrest report, in which he had written that Pyri-doxine causes ataxia and malaise, Morrison described these conditions as being “real laid back” and “feeling kind of lethargic.” According to Morrison, the nursing hand[416]*416book also stated, in regard to both medications, that users should “avoid alcoholic beverages or any other depressant.” Morrison opined that Pyridoxine “is not a strong depressant” and would not have caused the HGN “clues” exhibited by appellant. Morrison also noted that the Py-ridoxine bottle also contained a label stating, “Warning, do not drive or operate heavy machinery while taking this medication.” Morrison opined that appellant was intoxicated by use of “drugs based on the lack of odor of any alcoholic beverage.”
Officer Morrison transported appellant to a police station, where appellant declined to provide a breath sample, which precluded Morrison from obtaining “additional information” on appellant’s drug use. He explained that an HPD drug-recognition expert could only have performed a twelve-step examination of appellant if he had provided a breath sample, which was necessary to rule out alcohol or quantify any “additive effect.” Morrison noted that when a defendant refuses a breath test, an officer “can’t continue with the drug evaluation after that.”
Officer Morrison testified that although he did not have a video camera in his patrol car, he did videotape appellant’s performance on the sobriety tests at the police station. Morrison explained that appellant performed “a lot better at the station,” and he opined that “whatever [appellant] was on had time to pretty much go through his system because he was able to walk a lot better.” Although Morrison could understand appellant “a lot better” at the station, he opined that appellant’s “mental faculties” remained “about the same” at the station. When Morrison asked appellant to perform additional sobriety tests, appellant was not able to keep his hands at his side, his perception of “time and distance” was “way off,” and he swayed. Morrison noted that appellant failed a one-leg stand test and a walk-and-turn test, which demonstrated that he had lost the normal use of his mental and physical faculties. The videotape, which the State introduced into evidence, shows appellant’s performance of the tests at the station and reveals that at the conclusion of the walk-and-turn test, appellant stated, “I am under the influence of my medication. It is making me drowsy.”
Officer Morrison stated his “personal opinion” that appellant had “something else on board besides” his prescription medications because appellant’s “pupils were pinpoint at the station.” Morrison explained,
There is only one drug that would cause your pupils to be real pinpoint even in ambient lighting and that is a narcotic analgesic, a pain pill or a pain medication. That is the only medication that will make both pupils real tiny which his were. They were real pinpoint approximately three millimeters or 3.5 millimeters which indicated that [appellant] was on pain medication besides a [central nervous system] depressant.
Morrison then explained that he had been a Houston police officer for eighteen and one-half years and had made over one thousand arrests for driving-while-intoxicated offenses. Based upon his training and experience and his observations, he opined that appellant was intoxicated.
On cross-examination, when asked about his qualifications to make statements about the “affects of medications on the central nervous system,” Morrison admitted that he had taken a “course” to be a drug-recognition expert, but he had not taken the exam for certification. He further agreed that to be considered a drug-recognition expert, he would first have to pass the certification exam. However, Morrison reiterated that he was offering his opinions based upon his training and expe-[417]*417rienee, and he explained that Lisinopril, which was taken by his wife, did not affect her physical and mental faculties.
Officer Morrison agreed that although he suspected that “some sort of compound or chemical” was in appellant’s system, he conducted “standard” field-sobriety tests without consulting a drug-recognition expert. And he acknowledged that a drug-recognition expert’s evaluation of a defendant would consist of twelve parts and would include further evaluation of the defendant’s pupils as well as blood pressure tests. Morrison also agreed that without a drug-recognition expert or “blood work,” it would be “impossible to have anything other than a subjective opinion about what might be in” a defendant’s system.
Appellant testified that at the time of his arrest, he had been working on repairing his house, which had been severely damaged by Hurricane Ike. On the day of his arrest, appellant had finished a long day of repairing his house, he was dehydrated and exhausted, and he had not slept in several days. Appellant, who was taking “non-narcotic” medicine for his heart and his high blood pressure, noted that when his blood pressure is high, he gets “dizzy” and “drowsy” and “not being able to have food to eat to take this type of medication cause[s] extra ... dysfunction to [his] body.”
Appellant explained that just prior to his arrest, he was driving his car to the house of his mother-in-law for a meal. As he was driving, he was dodging debris in the street that had been left there from the hurricane. He explained that when he took his eyes off the road to reach for his cellular telephone, which was on the floorboard of his car, his car scraped the side of a curb, which caused his tire to blow out and him to hit his stomach and chest on the. steering wheel of his car. After he exited his car and leaned against it to catch his breath, Officer Morrison, approximately three or four minutes later, drove by and appellant flagged him down to ask for assistance.
Officer Morrison asked appellant for his identification and if he was “all right.” Appellant explained that he could not talk because he was dehydrated, hungry, tired, and just had an accident; he had not eaten since the day before and had been awake for three days. After Morrison asked appellant how much he had been drinking, appellant explained that he did not drink, but told Morrison that he takes “high blood pressure pills, TB medication,” and another medication. Appellant told Morrison that the medication was in his car, and Morrison retrieved the medication and told appellant that he was not “supposed to be operating this vehicle on medication.” Appellant explained that the medication was “prescribed by [his] doctor.”
Officer Morrison then looked at appellant’s eyes with a flashlight and took him to the police station, where appellant attempted to perform various sobriety tests pursuant to Morrison’s instructions. Appellant stated that he was “sluggish” as he had suffered a head injury.
Appellant further testified that he had taken his blood pressure pill “right before” he drove his car. He had noticed that his “blood pressure was up because [he] was lightheaded” and “dizzy.” Appellant explained that he feels lightheaded, dizzy, and weak when he has not been taking his blood pressure medication and, once he takes his medication, “after awhile” he “start[s] feeling better.” Appellant estimated that it generally takes 45 minutes for the medication to “kick in,” he took his pill around 3:15 p.m., and he entered in his car around 4:00 p.m.
[418]*418On cross-examination, appellant admitted that he had twice been previously convicted of felony offenses. He agreed that he felt lightheaded when he left his house, but he noted that he could feel the medication working. When the State asked appellant a series of questions about how often his medications made him dizzy, appellant answered sometimes “one time out of a week” or “two days out of the week.” Appellant also noted that the warning labels on his medications cautioned that he should not operate heavy equipment “unless familiar with medication.” Appellant explained that he was familiar with the medications because he had been taking them for three years. Although the medications periodically make him dizzy, appellant noted that he cannot stop this and sometimes the dizziness “comes out of nowhere.”
Sufficiency of the Evidence
In his second issue, appellant argues that the evidence is legally and factually insufficient to support his conviction for driving while intoxicated “due to medication” because it “was weak, unreliable, and irrelevant.” Appellant bases his argument on the arguments made in his first issue, in which he attacks the “reliability” of Officer Morrison’s testimony about appellant’s medications.
We review the legal sufficiency of the evidence by considering all of the evidence in the light most favorable to the verdict to determine whether any rational trier of fact could have found the essential elements of the offense beyond a reasonable doubt. Jackson v. Virginia, 443 U.S. 307, 318-19, 99 S.Ct. 2781, 2788-89, 61 L.Ed.2d 560 (1979). Evidence is legally insufficient when the “only proper verdict” is acquittal. Tibbs v. Florida, 457 U.S. 31, 41-42, 102 S.Ct. 2211, 2218, 72 L.Ed.2d 652 (1982). Our role is that of a due process safeguard, ensuring only the rationality of the trier of fact’s finding of the essential elements of the offense beyond a reasonable doubt. See Moreno v. State, 755 S.W.2d 866, 867 (Tex.Crim.App.1988). We give deference to the responsibility of the fact finder to fairly resolve conflicts in testimony, to weigh evidence, and to draw reasonable inferences from the facts. Williams v. State, 235 S.W.3d 742, 750 (Tex.Crim.App.2007). However, our duty requires us to “ensure that the evidence presented actually supports a conclusion that the defendant committed” the criminal offense of which he is accused. Id. We now review the factual sufficiency of the evidence under the same appellate standard of review as that for legal sufficiency. Ervin v. State, 331 S.W.3d 49, 52-56 (Tex.App.-Houston [1st Dist.] 2010, pet. ref d) (citing Brooks v. State, 323 S.W.3d 893, 894-913 (Tex.Crim.App.2010)).
A person commits the offense of driving while intoxicated if the person is intoxicated while operating a motor vehicle in a public place. Tex. Penal Code Ann. § 49.04(a) (Vernon Supp. 2011). The term “intoxicated” means (1) not having the normal use of mental and physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, a dangerous drug, a combination of those substances, or any substance into the body, or (2) having an alcohol concentration of 0.08 or more. Id. at § 49.01(2) (Vernon 2011). The substance that causes intoxication is not an element of the offense of driving while intoxicated that must be proved at trial. See id. § 49.04(a). Thus, the State can prove intoxication without proof of the type of intoxicant. See Gray v. State, 152 S.W.3d 125, 132 (Tex.Crim.App.2004).
Here, the jury heard the testimony of Officer Morrison, who explained that a witness had reported that appellant had been driving dangerously. Morrison followed [419]*419appellant, who Morrison saw driving in a dangerous manner. Morrison explained that, from the tests he attempted to administer to appellant at the scene, he believed appellant to be intoxicated. Appellant had no odor of alcohol on his person, so Morrison concluded that the intoxication was due to the ingestion of some type of drug. Morrison testified that appellant’s pupils exhibited signs consistent with intoxication by a drug. The jury was also presented with the videotape, which shows that appellant, at the police station, had difficulty following Morrison’s instructions. Moreover, on the videotape, appellant indicates that he was having trouble understanding Morrison because his medications were making him “drowsy.”
During his testimony, appellant denied being intoxicated, but, on cross-examination, he admitted that the medications that he takes sometimes make him “dizzy.” The jury was entitled to consider all of this evidence in finding that appellant was driving his car while intoxicated. See Cotton v. State, 686 S.W.2d 140, 148 n. 3 (Tex.Crim.App.1985) (enumerating nonexclusive list of signs recognized as evidence of intoxication, including staggered gait and slurred speech); Paschall v. State, 285 S.W.3d 166, 177 (Tex.App.-Fort Worth 2009, pet. refd) (holding evidence sufficient based, in part, on officer’s testimony regarding defendant’s performance on field-sobriety tests, videotape of field sobriety tests, and officer’s opinion that defendant had lost normal use of his mental and physical faculties); Compton v. State, 120 S.W.3d 375, 380 (Tex.App.-Texarkana 2003, pet. refd) (concluding that evidence was sufficient to support DWI conviction when jury heard officer’s testimony surrounding stop and viewed video-recording of defendant’s performance of field-sobriety tests); Henderson v. State, 29 S.W.3d 616, 622 (Tex.App.-Houston [1st Dist.] 2000, pet. ref'd) (concluding that officer’s testimony “that an individual is intoxicated is probative evidence of intoxication”); see also Tex. Transp. Code Ann. § 724.061 (Vernon 2011) (“A person’s refusal of a request by an officer to submit to the taking of a specimen of breath or blood, whether the refusal was express or the result of an intentional failure to give the specimen, may be introduced into evidence at the person’s trial.”).
Viewing the evidence in the light most favorable to the prosecution, we conclude that a rational trier of fact could have found beyond a reasonable doubt that appellant committed the offense of driving while intoxicated. Accordingly, we hold that the evidence is sufficient to support appellant’s conviction.
We overrule appellant’s second issue.
Admission of Evidence
In his first issue, appellant argues that the trial court erred in admitting “unreliable and irrelevant scientific evidence” to prove that he “was intoxicated due to medication” because Officer Morrison “was not certified as a drug recognition expert.” He also complains about Morrison’s testimony regarding the effects of the medications. Appellant argues that because the State’s evidence is not “sound and verifiable,” it is irrelevant. He asserts that the trial court “should not have admitted the unreliable evidence of an officer not adequately qualified under the rules to provide scientific evidence of intoxication due to medication.” Appellant further asserts that the State did not present any evidence of “the exact times of ingestion” or the “half life of the drug,” the jury could not have determined the time between when he took his medications and “how it may have affected intoxication,” and the State did not “sufficiently establish!]” that his poor performance on the [420]*420sobriety tests was “due to intoxication due to medication.”
We review a trial court’s ruling on a motion to suppress evidence for an abuse of discretion. Layton v. State, 280 S.W.3d 235, 240 (Tex.Crim.App.2009). We will uphold a trial court’s decision to admit evidence as long as the result is not outside the zone of reasonable disagreement. Id.
In support of his arguments, appellant relies on Layton, in which the Texas Court of Criminal Appeals held that “[w]ithout expert testimony to provide the foundation required to admit scientific evidence,” evidence regarding a defendant’s “use of prescription medications” is not relevant. 280 S.W.3d at 242. In Layton, the defendant was convicted of the offense of driving while intoxicated by the introduction of alcohol into the body. Id. at 237. The defendant objected to the admission of evidence pertaining to his use of Xanax and Valium. Id. Specifically, a videotape recording of the defendant’s traffic stop showed that the arresting officer had stopped the defendant at approximately 4:00 a.m. because the car that he was driving was protruding into an intersection. Id. The arresting officer asked the defendant if he had taken any medications, and the defendant acknowledged that he had taken both Xanax and Valium pursuant to his doctor’s prescriptions for the treatment of his high blood pressure. Id. The defendant then clarified that he had taken Valium at 2:00 p.m. the previous afternoon, but he had not taken any Xanax since the day before the traffic stop. Id. The arresting officer commented that the medications were for “anxiety,” not high blood pressure, and he asked the defendant whether he had read the “inserts” included with the medications. Id. The officer further told the defendant that “it probably was not a good idea to be drinking ‘on top of those.’ ” Id.
The defendant contended that such evidence “was inadmissible without the State proving the accuracy and reliability of the evidence and its relevance to whether [he] was intoxicated.” Id. at 240. He “noted that without extrapolation on the Xanax and Valium to determine their effect on the body, the State had not shown their relevance to the issue in question.” Id. The defendant argued that this evidence should not have been admitted “without expert testimony to provide foundation.” Id. at 237-38. The trial court admitted the evidence over the defendant’s objection. Id.
On appeal, the court of criminal appeals characterized the defendant’s challenge as follows:
Appellant’s contention on appeal is not that the evidence of his prescription-drug use is irrelevant per se, but that the relevance is conditional upon proof that it is sound and verifiable. Appellant argues that without that showing, the evidence is not reliable, and, therefore, irrelevant.
Id. at 241. The court explained that “[w]hen the relevance of evidence depends upon the fulfillment of a condition of fact, the court may admit the evidence contingent upon the introduction of evidence sufficient to support a finding of the fulfillment of the condition.” Id. (citing Tex.R. Evid. 104(b)). The court further explained that “[r]eliability of scientific evidence demands a certain technical showing and depends on whether the evidence has a basis in sound scientific methodology.” Id. (citing Jordan v. State, 928 S.W.2d 550, 555 (Tex.Crim.App.1996)).
The court then set forth, in significant detail, a trial court’s obligation in regard to the admission of scientific evidence:
[421]*421Scientific evidence has the ability to mislead a jury that is not properly equipped to judge the probative force of the evidence. Pursuant to Rule 702, it is the responsibility of the trial court to determine whether the scientific evidence offered is sufficiently reliable, as well as relevant, to help the jury in reaching accurate results. This places the trial judge in the role of a “gatekeeper,” whose responsibility it is to weed out inadmissible evidence based on a lack of reliability. The proponent of scientific evidence bears the burden of proving to the trial court, by clear and convincing evidence, that the evidence is sufficiently relevant and reliable to assist the jury in determining a fact in issue.
We have previously asserted that evidence derived from a scientific theory must meet three criteria in order to be reliable in any given case: “(a) the underlying scientific theory must be valid; (b) the technique applying the theory must be valid; and [ (c) ] the technique must have been properly applied on the occasion in question.” We also identified an nonexclusive list of factors that could influence a trial court’s determination of reliability. These include: (1) the extent to which the theory and procedure are accepted as valid by the relevant scientific community; (2) the technique’s potential rate of error; (3) the availability of experts to test and assess the method or technique; (4) the clarity and precision with which the underlying scientific premise and approach can be explained to the court; and (5) the knowledge and experience of the person(s) who applied the methodology on the occasion in question.
Id. (citations omitted). Applying these principles regarding the admission of scientific evidence, the court noted that, in the case before it, there was no evidence as to the dosage of the medications taken by the defendant, the exact times of ingestion, or the half-life of the drugs in the human body. Id. at 241-42. The court further noted that, in light of the length of time between the ingestion of the medications and the time of the defendant’s arrest, lay jurors were “not in a position to determine whether Xanax and Valium, taken more than 12 hours before arrest, would have any effect on [the defendant’s] intoxication.” Id. at 242. Finally, the court noted that there was no testimony indicating that the arresting officer had any medical knowledge regarding the uses of Xanax and Valium, or about the effect of combining the medications with alcohol. Id. Thus, the court of criminal appeals held that the trial court had erred in admitting evidence pertaining to the defendant’s use of Xanax and Valium “without the State first showing that the evidence was relevant” to intoxication. Id.
Here, the State contends that Layton is distinguishable because, in that case, the jury charge defined intoxication by reference only to alcohol, so the evidence pertaining to the narcotics was irrelevant. Although Layton is distinguishable on this point, the principles regarding the admission of scientific testimony that the court of criminal appeals set forth in Layton apply to our review of the trial court’s admission of Officer Morrison’s testimony about the prescription medications that Morrison located in appellant’s car and other evidence regarding these medications.
In support of its argument that Officer Morrison’s testimony was both relevant and reliable and he was qualified to offer his opinions, the State notes that Morrison testified that he had significant experience as an officer and had made over 1000 arrests for driving-while-intoxicated offenses, he had taken a field-sobriety-testing detection course, and he had taken a [422]*422drug-recognition-expert course in which he had learned about the “seven drug categories,” the ten systems of the human body, and “what the specific drugs do as far as the signs and symptoms to impair a person’s ability to operate a motor vehicle safely.” Morrison also had previously worked as a mortician and an emergency medical technician.
However, Officer Morrison conceded that he was not certified by HPD as a drug-recognition expert and had not taken the exam to obtain certification. The record establishes that HPD employs drug-recognition experts, Morrison is not one of them, and Morrison failed to consult a drug-recognition expert about appellant’s condition. Morrison agreed that he did not conduct the standard twelve-step examination that would have been conducted by a drug-recognition expert, and he explained that he did not contact such an expert in accord with HPD policy after appellant refused a breath test. Morrison’s testimony does not reveal that he had expert knowledge about the medications that appellant had taken or their effects on patients. He could state only that he was “familiar” with the medications based upon his review of a drug handbook for nurses, which Morrison consulted in conjunction with appellant’s arrest. Thus, there is no evidence that Morrison had previously studied or read about the medications and no evidence that he had any personal experience or training regarding the medications, other than his anecdotal report as to how one of the medications had generally affected his wife in the past.
Nevertheless, the trial court permitted Officer Morrison to testify, in great detail, about these medications and their effects both generally and specifically in regard to appellant. Morrison was permitted to compare how one of the medications affected his wife with how he opined that it had affected appellant. Morrison was also allowed to refer to general statements contained in a drug handbook for nurses regarding these medications, explain the symptoms and side effects of these medications, and define to the jury the medical terms contained in the handbook. Yet there is no evidence that Morrison had any specialized knowledge about these medical terms. More importantly, Morrison was allowed to specifically state that the medications could not have caused the “overwhelming signs” of intoxication or the HGN clues exhibited by appellant. Significantly, based upon this “expert” testimony, Morrison offered his opinion that appellant had “something else on board” besides his prescription medications.
The trial court also permitted Morrison to testify that once at the police station, appellant was “a lot better” because “whatever” appellant had in his system had “time to pretty much go through his system.” Morrison presented no foundation for his testimony regarding the length of time that these medications could have affected appellant or how these medications would have affected “whatever” other narcotic Morrison suspected that appellant had “on board.”
We conclude that the record before us demonstrates that Officer Morrison’s testimony concerning the medications at issue was neither relevant nor reliable and that Morrison was not qualified to offer such detailed testimony concerning appellant’s prescription medications or his understanding of the effects of the prescriptions on appellant. Accordingly, we hold that the trial court abused its discretion in allowing Morrison to testify regarding his opinion on these medications in conjunction with his ultimate opinion on appellant’s intoxication.
Having concluded that the trial court erred in admitting Officer Morrison’s [423]*423testimony about the medications and his opinion that appellant had “something else on board,” we must now conduct a harm analysis. A violation of evidentiary rules that results in the erroneous admission of evidence is non-constitutional error. See Tex.R.App. P. 44.2(b); see also Johnson v. State, 967 S.W.2d 410, 417 (Tex.Crim.App.1998). The appropriate harm analysis is therefore the one set out in Texas Rule of Appellate Procedure 44.2(b), which dictates that a non-constitutional error “that does not affect substantial rights must be disregarded.” Taylor v. State, 268 S.W.3d 571, 592 (Tex.Crim.App.2008) (quoting Tex.R.App. P. 44.2(b)). A substantial right is affected when an error has a substantial and injurious effect or influence in determining a jury’s verdict. King v. State, 953 S.W.2d 266, 271 (Tex.Crim.App.1997). Therefore, a criminal conviction should not be overturned for non-constitutional error if the appellate court, upon examining the record as a whole, has fair assurance that the error did not influence the jury, or had but slight effect. Cobb v. State, 85 S.W.3d 258, 272 (Tex.Crim.App.2002).
In assessing the likelihood that the jury’s decision was adversely affected by the error, we consider everything in the record, including any testimony or physical evidence admitted for the jury’s consideration, the character of the alleged error, and how it might be considered in connection with other evidence in the case. Motilla v. State, 78 S.W.3d 352, 355 (Tex.Crim.App.2002). We may also consider any jury instruction given by the trial court, the State’s theory and any defensive theories, closing arguments, and voir dire, if material to the claim. Id. at 355-56.
As explained above, Officer Morrison was not merely permitted to testify that, in his opinion, appellant was intoxicated due to the introduction of drugs or a controlled substance into his body. Such testimony would have been unremarkable and within the bounds of Morrison’s training and experience. Rather, the trial court permitted Morrison to testify in great detail about appellant’s prescription medications, the purposes of the medications, the side effects of the medications, how the medications affect the human body in general, and how the medications affected appellant specifically. Indeed, Morrison was allowed to testify that the medications could not have caused the “overwhelming signs” of intoxication exhibited by appellant and, in Morrison’s opinion, appellant had “something else on board.” A review of the record reveals that Morrison’s testimony pertaining to these medications and their effects constituted a substantial part of the State’s case.
During closing arguments, the State specifically argued to the jury that each member did not have to agree on “what drug it was” that caused appellant’s intoxication, and it noted that some jurors could believe that appellant was intoxicated by reason of his ingestion of prescription medications while others could believe that appellant had “something a little stronger on board, some sort of central nervous depressant.” (Emphasis added.) Although the State’s argument may have been legally correct and complied with the charge given, it is significant in regard to our harm analysis because, as previously noted, neither Officer Morrison’s extensive testimony about the medications at issue, nor his opinion that appellant had something else “on board,” should have been admitted into evidence for the jury to consider. In his closing argument, counsel for appellant obviously concluded that the evidence pertaining to appellant’s medications, Morrison’s expert testimony about the medications, and their effects on appellant’s intoxication, was a critical part of the State’s case. Appellant’s counsel de[424]*424voted a significant portion of his closing argument to challenging the reliability of Morrison’s opinions on the effects of appellant’s medications and their causal relationship to appellant’s intoxication. He argued that the jury should not consider Morrison to be an expert and, thus, his testimony was not rehable. In rebuttal, the State conceded that Morrison was not an expert, but the State continued to make reference not only to Morrison’s testimony regarding his general opinion of intoxication but also to his testimony about the medications.
We recognize that the State presented the videotape of the sobriety tests that appellant performed at the police station. As appellant has conceded in his brief, the videotape demonstrates that he did not perform well on the tests. We also note that the State, without objection, was able to introduce into evidence the hearsay testimony of an unidentified witness who reported appellant’s “crazy” driving to Officer Morrison.
However, the State was not merely required to prove that appellant had lost the normal use of his mental or physical faculties, but that he had done so “by reason of the introduction” of a “drug,” a “controlled substance,” a “combination of two or more” controlled substances or drugs, or “any other substance” into his body. Here, appellant testified that he was not intoxicated, but rather, he was exhausted, dehydrated, and sleep-deprived. In contrast, Morrison testified as to his opinion that appellant was intoxicated and his intoxication was caused by the introduction of a drug into his body. Again, significantly, he was permitted to opine that appellant’s medications could not have caused the “overwhelming signs” of intoxication exhibited by appellant and, therefore, appellant must have had “something else on board,” a point emphasized by the State in its closing argument. Because Morrison was permitted to provide such detailed and extensive testimony regarding appellant’s prescription medications and their potential effects, and because this testimony was unreliable, we cannot conclude with “fair assurance” that the trial court’s error in admitting his expert testimony “did not influence the jury” or had “but a slight effect” on the jury’s finding that appellant committed the offense of driving while intoxicated. See Layton v. State, No. 01-05-00950-CR, 2009 WL 1886162, at *3-4 (Tex. App.-Houston [1st Dist.] Jul. 2, 2009, pet. refd) (mem. op.). Accordingly, we hold that the trial court’s error affected appellant’s substantial rights. See Tex.R.App. P. 44.2(b).
We sustain appellant’s first issue.4
[425]*425Conclusion
We reverse the judgment of the trial court and remand for proceedings consistent with our opinion.
Justice BROWN, dissenting.