You can only be required to take medication if you are detained under the MHA. If you are on a psychiatric ward as a voluntary patient, you cannot be forced to take medication against your wishes. If you are in prison, then you are not under the MHA and its provisions therefore don’t apply to you.
If you are a detained patient, (even if you are detained for assessment under s2) then you can be required to take medication if the clinician in charge of your treatment thinks it is necessary.
Reasonable force can be used by your care team in administering the medication, although your care team will always try to secure your agreement first.