By G.S. 90-1, the Medical Society of the State of North Carolina is declared to be a body politic and corporate. By G.S. 90-2, the Board of Medical Examiners of the State of North Carolina, herein called the Board, was established “in order to properly regulate the practice of medicine and surgery.” The Board consists of seven regularly graduated physicians appointed by the Medical Society. G.S. 90-3. In addition to its authority and duty to examine applicants for license to practice medicine or surgery in this State, conferred upon it by G.S. 90-9, the Board is authorized by G.S. 90-14 to “revoke and rescind any license granted by it.” This statute, which was rewritten in 1977, provided at the time of the matters involved in this appeal:
“The Board shall have the power to revoke and rescind any license granted by it, when, after due notice and hearing, it shall find that any physician licensed by it *** has been guilty of any unprofessional or dishonorable conduct unworthy of, and affecting, the practice of his profession, or has been convicted in any court, State or Federal, of any felony or other criminal offense involving moral turpitude ***. The findings and actions of the Board of Medical Examiners in revoking or rescinding and refusing to issue licenses under this section, shall be subject to review upon appeal to the Superior Court, as hereinafter provided in this Article. The Board of Medical Examiners may, in its discretion, and upon such terms and conditions and for such period of time as it may prescribe, restore a license so revoked and rescinded.”
*543G.S. 90-14.1 prescribes the notice to be given to a licensee of a hearing convened to consider the revocation or recision of his license. It is not contended that the provisions of this statute were not fully complied with in this instance. G.S. 90-14.6 provides that at such hearing the admissibility of evidence is governed by the rules applicable to civil actions. In the present instance, it is not contended that any incompetent evidence was admitted or any competent evidence rejected. The scope of judicial review of an order of the Board revoking a license is set forth in G.S. 90-14.10, which provides:
“Upon the review of the Board’s decision revoking or suspending a license, the case shall be heard by the judge without a jury, upon the record, except that in cases of alleged omissions or errors in the record, testimony thereon may be taken by the court. The court may affirm the decision of the Board or remand the case for further proceedings; or it may reverse or modify the decision if the substantial rights of the accused physician have been prejudiced because the findings or decisions of the Board are in violation of substantive or procedural law, or are not supported by competent, material, and substantial evidence admissible under this Article, or are arbitrary or capricious. At any time after the notice of apipeal has been filed, the court may remand the case to the Board for the hearing of any additional evidence which is material and is not cumulative and which could not reasonably have been presented at the hearing before the Board.” (Emphasis added.)
G.S. 90-14.11 provides for appeal to the Supreme Court of North Carolina under rules of procedure applicable in other civil cases.
In 1974, the respondent was convicted in the Superior Court of Mecklenburg County of a felony — the making of a false and fraudulent proof of loss, including a false medical bill and a false physician’s report, for filing with an insurance company in relation to an automobile accident. No appeal was taken from that conviction and the resulting judgment thereon. G.S. 90-14, as it then read, expressly authorized the Board to revoke and rescind his license to practice medicine in this State, upon proof of such conviction, without any qualification or suspension of such revoca*544tion. The respondent does not dispute that authority in the present proceeding. Instead of doing so, the Board revoked the respondent’s license but suspended such order of revocation, thus giving the respondent a second chance. One of the conditions of such suspension of that order of revocation was that, for five years, the respondent “remain of good behavior and conduct his practice of medicine in accordance with proper professional and ethical standards.” No judicial review of that order of the Board was requested by the respondent. Nothing in the record indicates any request by him for clarification of its terms.
That order of the Board was entered 23 October 1974. The record of the hearing before the Board in the present proceeding contains clear evidence that, less than two weeks after that order was issued by the Board, the respondent wrote a prescription for Didrex at the request of a complete stranger, with no physical examination of him, no taking of his medical history and no questions as to any symptoms, aches or pains experienced by such person. According to the testimony of Prillaman, the stranger so requesting and receiving this prescription from the respondent, he gave the respondent no reason for desiring such prescription except that he was a truck driver and needed something to keep him awake.
Didrex is not listed by that name in the Controlled Substance Act, G.S. 90-86 et seq. That is a manufacturer’s trade name. It is also known as Speed. Its chemical name is Benzphetamine Hydrochloride. This being its chemical composition, it is a Schedule II controlled substance according to the provisions of G.S. 90-90(c) which states:
“The following controlled substances are included in this schedule:
* * *
“(c) Any material, compound, mixture, or preparation which contains any quantity of the following substances having a potential for abuse associated with a stimulant effect on the central nervous system unless specifically exempted or listed in another schedule [which is not the case with Didrex]:
*545“1. Amphetamine, its salts, optical isomers, and salts of its optical isomers.
* * *
“3. Methamphetamine, including its salts, isomers and salts of isomers.”
G.S. 90-90 also provides:
“This schedule [Schedule II] includes the controlled substances listed or to be listed by whatever official name, common or usual name, chemical name, or trade name designated. In determining that a substance comes within this schedule, the North Carolina Drug Authority shall find: a high potential for abuse; currently accepted medical use in the United States, or currently accepted medical use with severe restrictions; and the abuse of the substance may lead to severe psychic or physical dependence.” (Emphasis added.)
The record before us contains clear evidence that this was not an isolated, accidental oversight or mistake in judgment. The evidence, if true, as the Board obviously believed it to be, shows that within the next three and a half months the respondent, under virtually identical circumstances, gave to persons not medically examined by him, either physically or by questions, and whose medical histories and whose current conditions, symptoms or complaints were completely unknown to him, three other prescriptions for Didrex, two for Desoxyn and two for Butacaps.
Desoxyn and Butacaps are also controlled substances. “Desoxyn is a trade name used by Abbott Laboratories, North Chicago, Illinois, for Methamphetamine Hydrochloride.” State v. Newton, 21 N.C. App., 384, 386, 204 S.E. 2d 724 (1974). It is and at the time the respondent so prescribed it was, a Schedule II controlled substance and, like Didrex, a highly dangerous drug. Butacaps, or Butasol capsules, are Butabarbital, also a controlled substance, apparently somewhat less dangerous than Didrex and Desoxyn.
Judicial review of a revocation of license by order of the Board does not authorize the reviewing court to substitute its discretion for that of the Board. G.S. 90-14.10 provides that the court “may reverse or modify the decision [of the Board] if the *546substantial rights of the accused physician have been prejudiced because the findings or decisions of the Board are in violation of substantive or procedural law, or are not supported by competent, material, and substantial evidence admissible under this Article, or arbitrary or capricious.”
Clearly, the findings of the Board that the respondent wrote the above mentioned prescriptions “without determining whether or not such drugs were necessary for the treatment of any ailment or disease and not for any legitimate medical purpose and not in the course of a legitimate practice of medicine,” are supported by evidence in the record, although contradicted by the testimony of the respondent, himself. The findings of the Board, so supported, are conclusive upon judicial review of the Board’s order. See, In re Willis, 288 N.C. 1, 215 S.E. 2d 771 (1975), which involved judicial review of an order of the comparable Board of Law Examiners rejecting an applicant for license, and which cited in support of this pronouncement Konigsberg v. State Bar of California, 353 U.S. 252, 77 S.Ct. 722, 1 L.Ed. 2d 810 (1957), and Software v. Board of Bar Examiners, 353 U.S. 232, 77 S.Ct. 752, 1 L.Ed. 2d 796 (1957).
 Upon these findings of fact, the Board concluded that the conduct of the respondent, so found, constituted a violation of the laws of North Carolina, constituted dishonorable and unprofessional conduct affecting the practice of medicine and also constituted a failure to comply with the terms and conditions upon which the Board had suspended its 1974 order revoking the respondent’s license to practice medicine in North Carolina. The question now before us is whether the above mentioned findings of fact support the conclusions so drawn by the Board. In our opinion, they do.
Upon his appeal to this Court, the respondent does not deny the sufficiency of the evidence before the Board to support its said findings of fact. His contention on this appeal is that the statute under which the Board acted (G.S. 90-14) and the conditions of suspension of the 1974 order of the Board are both “vague and overbroad” and, thus, the order now before us for review, which revokes his license to practice medicine in North Carolina, violates his right to due process of law as established by the Constitution of North Carolina. Article I, § 19, and by the *547Fourteenth Amendment to the Constitution of the United States. We find no merit in these contentions.
 The Board clearly did not deny the respondent procedural due process. He was notified in writing of the charges against him, given ample time in which to prepare his defense, was present in person and represented by able counsel, of his choice, at the hearing, was confronted by his accusers, was given ample opportunity to cross-examine them and testified in his own behalf. Procedurally, the hearing was conducted in accordance with the statute and fulfilled the requirements of the Due Process Clause of the Federal and the Law of the Land Clause of the State Constitution.
 Obviously, the charges brought before the Board against the respondent have no relation whatever to any of the freedoms protected by the First Amendment to the Constitution of the United States. Consequently, the “vague-overbroad” challenge to the statute and to the 1974 order of the Board is not to be weighed in this case in the delicate scales required to be used in cases where First Amendment freedoms are at stake. United States v. Powell, 423 U.S. 87, 96 S.Ct. 316, 46 L.Ed. 2d 228 (1975); United States v. Mazurie, 419 U.S. 544, 95 S.Ct. 710, 42 L.Ed. 2d 706 (1975).
In United States v. Powell, supra, 423 U.S. at 93, the Court, speaking through Mr. Justice Rehnquist, said, in a case not involving First Amendment freedoms, “[S]training to inject doubt as to the meaning of words where no doubt would be felt by the normal reader is not required by the ‘void for vagueness’ doctrine, and we will not indulge in it.” In Colten v. Kentucky, 407 U.S. 104, 110, 92 S.Ct. 1953, 32 L.Ed. 2d 584 (1972), in which also First Amendment rights were not involved, the Court, speaking through Mr. Justice White, said: “The root of the vagueness doctrine is a rough idea of fairness. It is not a principle designed to convert into a constitutional dilemma the practical difficulties in drawing criminal statutes both general enough to take into account a variety of human conduct and sufficiently specific to provide fair warning that certain kinds of conduct are prohibited. We agree with the Kentucky Court when it said: ‘We believe that citizens who desire to obey the statute will have no difficulty in understanding it.’ ” As Mr. Justice Holmes, speaking for the Court, in Nash v. United States, 229 U.S. 373, 377, 33 S.Ct. 780, 57 *548L.Ed. 1232 (1913), said, “The law is full of instances where a man’s fate depends on his estimating rightly, that is, as the jury subsequently estimates it, some manner of degree.”
G.S. 90-14 authorizes revocation of the license to practice medicine or surgery where the licensee “has been guilty of any unprofessional or dishonorable conduct unworthy of, and affecting, the practice of his profession.” The 1974 order of the Board suspended the then revocation of the respondent’s license to practice on condition that he “conduct his practice of medicine in accordance with proper professional and ethical standards.”
It is reasonable to assume, as we do, that as one goes toward the outer edges of the concepts of “unprofessional,” “dishonorable” or “professional and ethical standards,” with reference to the practice of medicine, as in the practice of law or the other learned professions, he reaches an area in which there is room for difference of opinion among the most honorable and respected practitioners. There is, we are satisfied, no sharply defined drop off point between ethical and professional medical practice and that which is unethical and unprofessional. However, there is at and around the central core of these concepts much conduct which so clearly constitutes improper practice that few, if any, members of the profession would seriously claim to be unaware that such conduct is not consistent with these concepts.
 It would obviously be futile to attempt to catalog in a statute, or in an order of the Board conditionally revoking the license of a practitioner, every conceivable improper practice in which the licensee is forbidden to engage. Neither the Federal nor the State Constitution requires such a tedious exercise in futility in order to save a disciplinary statute, or order, from attack on the ground of vagueness and over-breadth. In the application of such statute or order to subsequent medical practices by a licensee, not involving his First Amendment freedoms, the facts of the case at hand must determine the decision of the courts as to vagueness and over-breadth. United States v. Mazurie, supra. The test is whether a reasonably intelligent member of the profession would understand that the conduct in question is forbidden.
 We think it obvious that any reasonably intelligent physician would know that to prescribe a highly dangerous drug for a com-*549píete stranger, without making any examination of the patient or any inquiry as to his medical history or current symptoms and complaints, would be included within the phrase “unprofessional or dishonorable conduct unworthy of, and affecting, the practice of his profession,” the terminology of G.S. 90-14, and would not constitute practice “in accordance with proper professional and ethical standards,” the language of the Board’s 1974 order. Thus, we find both the statute and the Board’s order easily survive the “vague and over-broad” attack by the respondent when “examined in the light of the facts of the case at hand.” United States v. Mazurie, supra.
In any event, in the present case, the respondent, himself, testified that, in his opinion, it is not proper medical practice to prescribe Didrex or any other stimulant just to keep the patient awake. Again, he testified that he knew Desoxyn was a Class II controlled substance and stated that, in his opinion, it would not be proper medical practice for any doctor to prescribe these drugs for the purposes “testified to by Mr. Prillaman, Mr. Madden and Mr. Arnold.” His contention is that he prescribed them for a different purpose. Thus, we are brought to the simple question of whether the respondent prescribed Didrex and Desoxyn for these individuals for the purpose and under the circumstances to which the individuals each testified, or prescribed them for a different purpose and under different circumstances as the respondent testified. This is not a question of law but a question of fact upon which the Board had before it conflicting testimony. The credibility of the witnesses and the resolution of conflicts in their testimony is for the Board, not a reviewing court, and the findings of the Board supported, as these findings are, by competent evidence, are conclusive upon judicial review of the Board’s order.
Furthermore, in the order under review, the Board concluded that the respondent’s conduct, in the six instances found by the Board to have occurred, “constituted a violation of the laws of North Carolina.” Another condition upon which the Board suspended its 1974 revocation of the respondent’s license, was that “for a period of five (5) years from this date Gordon M. Wilkins, M.D. shall not violate a State or Federal law.” In State v. Best, 292 N.C. 294, 310, 233 S.E. 2d 544 (1977), speaking through Justice Huskins, we said:
*550“Where a licensed physician merely writes a prescription for a controlled substance listed in Schedules II, III, IV or V, and nothing more, such act is not a violation of G.S. 90-95(a)(l). However, if that prescription is written outside the normal course of professional practice in North Carolina and not for a legitimate medical purpose, the physician violates G.S. 90-108.”
In the order here under review, the Board found as a fact, in connection with the issuance of each of the six prescriptions in question, the respondent issued the prescription “not for any legitimate medical purpose and not in the course of the legitimate practice of medicine.” These findings, being supported by competent evidence in the record, are conclusive on judicial review of the order of the Board.
G.S. 90-14 does not authorize the revocation of a license of a physician on the ground that he has violated a law of this State or a Federal law unless and until he has been convicted thereof. The record before us discloses that the respondent was charged in the criminal courts of Mecklenburg County with the violation of the applicable statute of this case in the writing of the said six prescriptions, but he was not convicted and the criminal charges against him were dropped when a mistrial resulted from the inability of the jury to reach a verdict.
 However, the 1974 order of the Board was issued in consequence of the respondent’s actual conviction of a felony in the Superior Court of Mecklenburg County, so that at that time an unqualified revocation of the respondent’s license was within the authority of the Board. The Board suspended its revocation of his license, at that time, on condition that he “shall not violate a State or Federal law.” The respondent accepted that condition of suspension of the revocation of his license. It is clear and unequivocal. We find nothing in G.S. 90-14, or any other statute relating to the authority of the Board, which precludes the Board from suspending its order of revocation upon such condition. Compare, G.S. 15A-1343(b)(l) authorizing one convicted of a criminal offense to be placed on probation upon condition that he “not commit any criminal offense.”
 A proceeding before the Board for the revocation of a physician’s license on the ground that he has violated such condition of *551a prior, suspended order of revocation, is a civil proceeding. Consequently, such violation of the condition of suspension of the prior order does not have to be shown beyond a reasonable doubt, but only by a preponderance of the evidence. In re Kincheloe, 272 N.C. 116, 157 S.E. 2d 833 (1967), cert. den., 390 U.S. 1024 (1968).
 We, therefore, conclude that the findings of fact made by the Board are fully supported by competent evidence in the record, these findings support the conclusions of law reached by the Board and those conclusions support the order of the Board revoking the license of the respondent to practice medicine in North Carolina. The revocation of the license is authorized by and is in accord with both G.S. 90-14 and the conditions of the 1974 order of the Board.
 There remains for consideration only the contention of the respondent that the Superior Court erred in its denial of his motion, filed before the hearing in the Superior Court, that the matter be remanded to the Board for further proceedings. The alleged ground of the motion is that he has been denied by the Board the equal protection of the laws in that the order of the Board was based “wholly or in part upon the petitioner’s [respondent’s] race and color.”
The motion for remand states, “It is the petitioner’s position that white doctors, similarly situated and upon similar conduct and behavior have not been treated as severely as petitioner and that this disparate treatment constitutes racially discriminatory action by the Board in violation of petitioner’s constitutional rights.” The motion requested the court to remand the matter to the Board and allow him 180 days “discovery time so that petitioner can take the depositions of the current and past members of the. Board of Medical Examiners, inspect prior records of the Board of Medical Examiners involving other cases, and promulgate to the Board interrogatories designed to determine whether the action taken against petitioner had a racial intent and/or impact.”
The record discloses not one shred of evidence of such discrimination or that the race of the respondent had any bearing whatever upon the order of the Board. The respondent was notified in writing of the charges against him on 31 August 1976. He filed his answer thereto on 29 September 1976, simply deny*552ing each allegation. On 26 October 1976, he was given notice that the matter would be heard by the Board and the hearing was had on 8 December 1976. Nothing whatever in the record indicates that in the intervening three months the respondent requested permission to examine, or made any effort to examine or make any inquiry into, actions of the Board in cases involving other physicians. No evidence of any action of the Board indicating bias against or antipathy toward physicians of the respondent’s race was presented or even suggested to the Superior Court in support of this motion. From the time of the respondent’s notice of appeal to the Superior Court to the filing of his brief in this Court 13 months elapsed. In that time, the respondent has apparently discovered nothing whatever to justify his accusation against the Board. In his brief in this Court, he says:
“After the hearing [before the Board], however, Dr. Wilkins became aware of matters, not of record, that caused him to question the objectivity with which his case was reviewed by the Board. Specifically, Dr. Wilkins received statements, became aware of rumors and read media coverage of other situations — all of which suggested that black doctors in general and Dr. Wilkins in particular were being subjected to higher standards of review by the Board and were subjected to consistently more severe punishment at the hands of the Board than were white doctors similarly situated.
“As such rumors persisted in the spring and summer of 1966 [presumably 1976], Dr. Wilkins, through counsel, sought to develop a record necessary to bring these issues before the court for determination on the merits. N.C. General Statutes Sec. 90-14.8 to 14.10 does not provide for discovery as is contemplated in the Rules of Civil Procedure. However, in Section 14.10, the opportunity is presented to a respondent to petition the Superior Court for remand to allow development of the record regarding matters not previously covered in the proceedings below. This, Dr. Wilkins sought to do by motion filed on 5 July 1977.”
The Superior Court was not required to remand this matter to the Board for further proceedings in the absence of some preliminary showing by the respondent of basis for his accusation *553of racial discrimination and prejudice against the respondent. Now, eight months after the denial of the motion in the Superior Court and 15 months after the issuance of the order of the Board, the respondent brings to our attention no basis for his allegation except unspecified “statements,” “rumors” and “media coverage” with no indication as to the source or credibility of such alleged bases for his accusation.
The respondent’s accusation against the Board and his exception to the denial of his motion by the Superior Court do not merit detailed. discussion. His counsel appears to proceed upon the theory that the mere facts that the respondent in a revocation of license proceeding, or a defendant in a criminal action, is a member of the Negro race and has been found guilty of the alleged misconduct is sufficient to make out a prima facie case that the administrative body or the jury which ruled against him was racially biased. Such a contention is patently absurd.
In the present instance, moreover, we are not limited to the obvious insufficiency of the respondent’s argument in support of his contention. The record discloses that the Board in 1974 had ample basis for an unqualified, instantly effective, revocation of the respondent’s license for his conviction of a felony in connection with the practice of medicine. With no obligation whatever to do so, the Board gave him a second chance. He has simply failed to measure up to the reasonable conditions imposed upon that opportunity by the Board.
Notwithstanding the findings and order of the Board in the present matter, its order of revocation has been stayed pending judicial review, first in the Superior Court and now in this Court. Thus, the respondent has been allowed to continue the practice of medicine for more than 15 months after the order of the Board revoking his license to do so was entered. The order of the Board in the 1974 proceeding, the record of the hearing before the Board in this proceeding, and the treatment of the respondent since that order was entered, clearly belie his charge that the revocation of his license to practice medicine in this State is due to prejudice against members of his race.