Plaintiff brought an action against Surf-side Pharmacy and Mt. Sinai Hospital on a theory that defendants’ negligent acts aggravated a preexisting mental condition. The trial court disallowed the testimony of the plaintiff’s two expert physicians and ultimately directed a verdict in favor of the defendants. We affirm.

*902The only expert testimony presented by the plaintiff to establish that the defendants' acts caused an aggravation of the plaintiffs preexisting condition was that of Drs. Shellow and Gilbert.

As to Dr. Shellow, we find that: (1) the hypothetical question by which the causal relationship and aggravation of a psychiatric disorder were to be established failed to identify the preexisting condition and thus any testimony based on it was properly excluded; see Steiger v. Massachusetts Casualty Insurance Co., 273 So.2d 4 (Fla. 3d DCA 1973) (the nature of the plaintiffs psychiatric condition at the time of the accident was a necessary element in a hypothetic question which purported to state a medical history of the plaintiff); (2) direct and cross-examination of the expert revealed that he had no knowledge of the plaintiffs preexisting condition from which he could form an opinion of its aggravation;1 Caputo v. Taylor, 403 So.2d 551 (Fla. 1st DCA 1981), pet. for review denied, 412 So.2d 464 (Fla. 1982); see also Husky Industries, Inc. v. Black, 434 So.2d 988 (Fla. 4th DCA 1983); Tarkoff v. Schmunk, 117 So.2d 442 (Fla.2d DCA 1959); and (3) his opinion amounted to little more than a guess. Husky Industries, Inc.

Turning to Dr. Gilbert, we conclude, as we did with respect to Dr. Shellow, that he had no knowledge of the preexisting condition from which he could form an opinion.2 See Caputo; Husky Industries, Inc.

The only two experts presented by the plaintiff to establish that the incidents in question caused an aggravation of her preexisting condition were unable to do so. Thus, we conclude that the directed verdict was properly entered. Caputo, 403 So.2d at 554.

Affirmed.