2.—(1) The claimant is—
(a)undergoing medical or other treatment as an in-patient in a hospital or similar institution; or
(b)recovering from such treatment in circumstances in which the Secretary of State is satisfied that the claimant should be treated as having limited capability for work.
(2) The circumstances in which a claimant is to be regarded as undergoing treatment falling within sub-paragraph (1)(a) include where the claimant is attending a residential programme of rehabilitation for the treatment of drug or alcohol dependency.
(3) For the purposes of this paragraph, a claimant is to be regarded as undergoing treatment as a patient in a hospital or similar institution only if that claimant has been advised by a health care professional to stay overnight or for a longer period following medical or other treatment.